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Copyright

by

James Stephen Doran

2004

The Dissertation Committee for James Stephen Dorancertifies that this is the approved version of the following dissertation:

On the Market Price of Volatility Risk

Committee:

Ehud Ronn, Supervisor

Stephen Magee

Ramesh Rao

Stathis Tompaidis

Li Gan

On the Market Price of Volatility Risk

by

James Stephen Doran, B.A.

DISSERTATION

Presented to the Faculty of the Graduate School of

The University of Texas at Austin

in Partial Fulfillment

of the Requirements

for the Degree of

DOCTOR OF PHILOSOPHY

THE UNIVERSITY OF TEXAS AT AUSTIN

May 2004

Dedicated to my wife Heather, my parents Charles and Elaine, and to my

son Jackson.

Acknowledgments

I wish to thank the multitudes of people who helped me.

I would like to single out especially my advisor, Ehud Ronn, my parents,

Charles and Elaine, and my wife Heather

This work would never have to come to fruition without the guidance and

support of my advisor and friend Ehud Ronn. His persistence and belief in me

was the necessary and sufficient condition required for successful completion

of this document.

Without the words of wisdom and teaching of my parents, I would never have

persisted in the pursuit of my goals, from the smallest task to the largest

achievement.

Finally, if it had not been for my wife, with which all things begin and end, I

would never have been at this stage in life that I am at today. It is our lives

together that allow us individually to succeed.

. . .

v

On the Market Price of Volatility Risk

Publication No.

James Stephen Doran, Ph.D.

The University of Texas at Austin, 2004

Supervisor: Ehud Ronn

This work examines the extent of the bias between Black-Scholes (1973)/Black

(1976) implied volatility and realized term volatility, estimation of the market

price of volatility risk, and option model fit in the natural gas market. To

examine this bias I institute a stochastic volatility data generating process,

and demonstrate the bias through Monte Carlo simulation of the underlying

parameters. This provides a numerical justification for testing the importance

of a risk premia for volatility. I implement empirical tests for the market

price of volatility risk by analyzing at-the-money options on the S&P 500 and

S&P 100. Further, I extend the study by considering options on natural gas

contracts by examining option model fit for a variety of parametric candi-

dates. Using risk-neutral parameter estimates I re-estimate the market price

of volatility risk using the full cross-section of option prices. The findings

demonstrate a negative market price of volatility risk, and show that this risk

is a significant component of the bias between Black-Scholes/Black implied

volatility and realized term volatility.

vi

Table of Contents

Acknowledgments v

Abstract vi

List of Tables x

List of Figures xiii

Chapter 1. Introduction 1

1.1 Evidence on the Market Price of Volatility Risk . . . . . . . . 9

Chapter 2. The Bias in Black-Scholes/BlackImplied Volatility 14

2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.2 The Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.2.1 Stochastic Volatility . . . . . . . . . . . . . . . . . . . . 14

2.3 Estimation of the Bias in BSIV/BIV . . . . . . . . . . . . . . . 19

2.3.1 Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.3.1.1 Measurement Error . . . . . . . . . . . . . . . . 21

2.3.2 Estimating the bias . . . . . . . . . . . . . . . . . . . . 22

2.3.2.1 Equity Bias . . . . . . . . . . . . . . . . . . . . 22

2.3.2.2 Modeling of the TSOV . . . . . . . . . . . . . . 26

2.3.2.3 Gas Bias . . . . . . . . . . . . . . . . . . . . . . 30

2.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Chapter 3. Monte Carlo Simulation and Estimation of the Mar-ket Price of Volatility Risk 36

3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

3.2 Monte Carlo Simulation . . . . . . . . . . . . . . . . . . . . . . 37

vii

3.2.1 Stochastic Volatility Simulation . . . . . . . . . . . . . . 41

3.2.1.1 Perfect and Zero Correlation Cases . . . . . . . 41

3.2.1.2 Equity . . . . . . . . . . . . . . . . . . . . . . . 42

3.2.1.3 Commodities . . . . . . . . . . . . . . . . . . . 45

3.2.2 Jump Model Simulation . . . . . . . . . . . . . . . . . . 47

3.2.2.1 Results of Pure Jump Model-Equity . . . . . . 50

3.2.2.2 Results of Pure Jump Model-Commodities . . . 52

3.2.2.3 Results of Proportional Jump Model- Equity . . 54

3.2.2.4 Results of Proportional Jump Model-Commodities 55

3.2.2.5 Results of Jump Models with Negative MarketPrice of Volatility Risk- Equity . . . . . . . . . 56

3.2.2.6 Results of Jump Models with Negative MarketPrice of Volatility Risk- Commodities . . . . . . 57

3.2.3 Results of Prior Parameter Estimates . . . . . . . . . . 58

3.3 Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

3.3.1 Simulation within a Simulation . . . . . . . . . . . . . . 61

3.3.2 Estimation Using Mean Reverting Framework . . . . . . 65

3.3.3 Estimation of λσ . . . . . . . . . . . . . . . . . . . . . . 66

3.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Chapter 4. Empirical Performance of Option Models for Nat-ural Gas and Estimation of the Market Price(s) ofRisk 74

4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

4.2 Modeling Issues . . . . . . . . . . . . . . . . . . . . . . . . . . 80

4.2.1 Data Generating Process for the Double Jump Model . 80

4.2.2 Double Jump Option Model . . . . . . . . . . . . . . . . 83

4.2.3 Independent Double Jumps and TSOV considerations . 85

4.3 Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

4.3.1 Understanding the volatility in gas markets . . . . . . . 89

4.4 Model Estimation . . . . . . . . . . . . . . . . . . . . . . . . . 90

4.4.1 Estimation Technique . . . . . . . . . . . . . . . . . . . 92

4.4.2 Structural Parameter Estimation and Model Performance 94

4.4.3 Out of sample pricing performance . . . . . . . . . . . . 101

viii

4.5 Mean-Reversion in Stochastic Volatility . . . . . . . . . . . . . 103

4.6 Proposed Algorithms . . . . . . . . . . . . . . . . . . . . . . . 106

4.6.1 Parameter Estimation, including Market Price of Risk . 106

4.6.2 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

4.7 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

Tables and Figures 113

Appendices 176

Appendix A. Bias in Black-Scholes/Black Volatiltiy 177

A.1 Non-recombining Bushy Lattice Framework . . . . . . . . . . . 177

A.2 Demonstrating greater risk-neutral volatility than real-world volatil-ity with negative market price of volatiltiy risk . . . . . . . . . 179

Appendix B. Characteristic Functions for Candidate Option Pric-ing Models 181

B.1 Correlated Double-Jump Model . . . . . . . . . . . . . . . . . 181

B.2 Independent Double-Jump Model . . . . . . . . . . . . . . . . 182

B.3 Barone-Adesi and Whaley Analytical Approximation for Amer-ican Option Prices . . . . . . . . . . . . . . . . . . . . . . . . . 183

Index 186

Bibliography 187

Vita 195

ix

List of Tables

1 Descriptive statistics for the S&P 100 and S&P 500 . . . . . . 125

2 Gas Contracts . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

3 Number of days with greater than 5% price movements . . . . 127

4 Number of days with greater than 10% price movements . . . 127

5 Bias in BSIV in S&P 100 contracts . . . . . . . . . . . . . . . 128

6 Bias in BSIV in S&P 500 contracts . . . . . . . . . . . . . . . 129

7 TSOV Specification Fit . . . . . . . . . . . . . . . . . . . . . . 130

8 Bias in BIV in Natural Gas Futures . . . . . . . . . . . . . . . 131

9 Perfect and Zero Correlation Case . . . . . . . . . . . . . . . . 132

10 Equity Proportional Volatility Model with Market Price of Volatil-ity Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

11 Equity Process Stochastic Volatility Table . . . . . . . . . . . 134

12 Commodity Process Stochastic Volatility Table . . . . . . . . 135

13 Equity Jump Table . . . . . . . . . . . . . . . . . . . . . . . . 136

14 Equity Proportional Volatility Jump Table . . . . . . . . . . . 137

15 Commodity Jump Table . . . . . . . . . . . . . . . . . . . . . 138

16 Commodity Proportional Volatility Jump Table . . . . . . . . 139

17 Commodity Proportional Volatility Jump Model with MarketPrice of Volatility Risk . . . . . . . . . . . . . . . . . . . . . . 140

18 Mean-Reversion regression of instantaneous volatility and BSIVfrom 30 day options . . . . . . . . . . . . . . . . . . . . . . . . 141

19 Equity Mean Reversion Regression . . . . . . . . . . . . . . . 142

20 Commodity Mean Reversion Regression . . . . . . . . . . . . . 143

21 Black Implied Volatility . . . . . . . . . . . . . . . . . . . . . 144

22 Black Implied Volatility Cont.. . . . . . . . . . . . . . . . . . . 145

23 Out of Sample Pricing Errors- 1 Day Ahead . . . . . . . . . . 146

24 Out of Sample Pricing Errors- 5 Day Ahead . . . . . . . . . . 147

25 Percentage Pricing Errors . . . . . . . . . . . . . . . . . . . . 148

x

26 In Sample Parameter Estimation and Fit of Gas Price Process 149

27 Parameter Estimation for BIV less than 50% . . . . . . . . . . 150

28 Parameter Estimation for BIV less than 80% . . . . . . . . . . 151

29 Parameter Estimation for BIV less than 100% . . . . . . . . . 152

30 Parameter Estimation for BIV less than 150% . . . . . . . . . 153

31 Parameter Estimation for BIV less than 200% . . . . . . . . . 154

32 Parameter Estimation for BIV less than 300% . . . . . . . . . 155

33 Parameter Estimation for All options in 2000 . . . . . . . . . . 156

34 Parameter Estimation for All options in 2001 . . . . . . . . . . 157

35 Parameter Estimation for All options in 2002 . . . . . . . . . . 158

36 Parameter Estimation for All options in 2003 . . . . . . . . . . 159

37 Parameter Estimation for Long-Term Options . . . . . . . . . 160

38 Parameter Estimation for Medium-Term Options . . . . . . . 161

39 Parameter Estimation for Short-Term Options . . . . . . . . . 162

40 Parameter Estimation for Long-Term Options in the WinterMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

41 Parameter Estimation for Medium-Term Options in the WinterMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

42 Parameter Estimation for Short-Term Options in the WinterMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165

43 Parameter Estimation for Long-Term Options in the SpringMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166

44 Parameter Estimation for Medium-Term Options in the SpringMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167

45 Parameter Estimation for Short-Term Options in the SpringMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168

46 Parameter Estimation for Long-Term Options in the SummerMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

47 Parameter Estimation for Medium-Term Options in the Sum-mer Months . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

48 Parameter Estimation for Short-Term Options in the SummerMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171

49 Parameter Estimation for Long-Term Options in the Fall Months172

50 Parameter Estimation for Medium-Term Options in the FallMonths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173

xi

51 Parameter Estimation for Short-Term Options in the Fall Months174

52 Market Price(s) of Risk . . . . . . . . . . . . . . . . . . . . . . 175

xii

List of Figures

1 Cross-sectional model comparision . . . . . . . . . . . . . . . . 114

2 VIX index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

3 TSOV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

4 January Natural Gas Contracts Implied Volatility . . . . . . . 117

5 August Natural Gas Contracts Implied Volatility . . . . . . . 118

6 Cross-section BSIV plots . . . . . . . . . . . . . . . . . . . . . 119

7 Cross-section BIV plots . . . . . . . . . . . . . . . . . . . . . . 120

8 Simulation within a simulation technique . . . . . . . . . . . . 121

9 BIV plots for long-term 2001 contracts . . . . . . . . . . . . . 122

10 BIV plots for long-term 2002 contracts . . . . . . . . . . . . . 122

11 BIV plots for medium-term 2001 contracts . . . . . . . . . . . 123

12 BIV plots for medium-term 2002 contracts . . . . . . . . . . . 123

13 BIV plots for short-term 2001 contracts . . . . . . . . . . . . . 124

14 BIV plots for short-term 2002 contracts . . . . . . . . . . . . . 124

xiii

Chapter 1

Introduction

To what extent is implied volatility a biased or unbiased predictor of

future realized volatility? The answer to this question is important for a

variety of reasons, impacting option trading, volatility forecasting, and overall

risk management. Understanding this bias could lead to resolving issues such

as why option traders tend to be short and whether forward prices are upward-

or downward-biased predictors of spot prices. The predictive power of implied

volatility will be explored in both the equity and commodity markets, as one

of my objectives in this work is to understand this bias.

There exists a rich literature on the computation and interpretation

of implied volatility, following closely upon the heels of the derivation of the

Black-Scholes option pricing formula. Christensen and Prabhala (1998) com-

pared implied volatility to an ex-post estimate of return volatility. By per-

forming a time-series analysis of pre- and post-87 data, they suggest that the

implied volatility of S&P 100 index options is an unbiased and efficient predic-

tor of future volatility. They were able to show that implied volatility remains

an efficient estimator even when including past volatility in the specification.

Others, such as Jorion (1995) and Lamoureux and Lastrapes (1993), consid-

1

ered foreign currency options and have suggested that implied volatility, while

efficient, is a biased predictor of future realized volatility.

If Black-Scholes implied volatility is truly an unbiased predictor of fu-

ture realized term volatility, this is consistent with the hypothesis that the

Black-Scholes model is the “true” model for stock prices, and that there is

no model misspecification. Such a conclusion would appear inconsistent with

the volatility skew present in option prices. In fact, we should expect Black-

Scholes/Black implied volatility to be biased, when we account for the market

price of volatility risk within a jump and/or stochastic volatility framework.

The estimation will lead to the conclusion that Black-Scholes implied volatil-

ity is an upward-biased predictor, which I will relate to the underlying data

generating process.

The evolution of the commodity markets differs from the tradition eq-

uity/index markets, and reporting on the volatility bias and underlying pa-

rameters in this market is the next objective. I will use Black’s formula for

the implied volatility (BIV) for the commodity simulation case. Commodities

contracts add additional complexity not prevalent for equities. The presence

of a significant term structure of volatility (TSOV), as well as seasonality, re-

quires additional modeling, and further complicates estimation. Thus I resort

to estimating the necessary TSOV parameters that reduce pricing errors by

postulating three parametric forms for the term structure. The findings sug-

gest that a reciprocal specification for the TSOV best fits the model when

there is a severe “ramping up” of volatility, versus the traditional Schwartz

2

(1997) specification and a quadratic form. As for seasonality, it was necessary

to separate the contracts by months. This allows further insight into the effects

of stochastic volatility premiums on winter versus summer months. There is

an additional concern with liquidity issues, and/or sticky prices, due to low

turnover. Focusing on gas contracts versus oil or electricity, minimized these

concerns since the volume is sufficient and data is readily available. After

accounting for these idosyncrasies, demonstrating BIV is an upward-bias pre-

dictor of future realized volatility can be accomplished in similar methodology

to the upward-bias in BSIV.

After estimation, the intent is to examine current option pricing models

to determine how well each model can explain this bias. Whereas Black and

Scholes (1973) postulated a geometric Brownian motion, papers such as Hull

and White (1987), Heston (1993), and Bates (1994, 1996) introduced stochas-

tic volatility and jumps into the data generating process, with the intended

implication that prices may incorporate premiums for jumps and changes in

volatility. Incorporating both stochastic volatility and jumps in the formu-

lation, I consider the individual and combined effects of the underlying pa-

rameters and how they either contribute to, or diminish, the bias in implied

volatility.

Recent literature has expanded upon these models by incorporating

additional factors such as jumps in volatility, multiple volatility factors, and

alternative power coefficients. While these models help improve the under-

standing of the evolution of options markets, there are unanswered questions

3

that can be resolved without the need for such additional price-process model-

ing. In addition, there appears to be limited significant improvement to overall

model fit.1

The parameter of particular interest is the market price of volatility risk.

There is a wide body of literature on stochastic volatility models, but very lim-

ited information on the market price of volatility risk. Only recently, findings

in Bakshi and Kapadia (2001), Coval and Shumway (2001), Pan (2000), and

others address the direction and magnitude of market price of volatility risk.

The hypothesis is that the market price of volatility risk is indelibly linked

to the bias in Black-Scholes implied volatility: The process volatility and in-

teraction with the market price of volatility risk, determines the magnitude

of the bias. If market price of volatility risk is negative, this can potentially

explain the upward-bias we observe in Black-Scholes implied volatility as well

as contribute to Bates’ (1996) finding that out-of-the money (OTM) puts are

volatility skew expensive relative to other options. Traders short OTM puts

require compensation for volatility risk, independent of any jump intensity or

jump size risk that may also be included. Eraker (2001) and Bates (2000)

have documented the Sharpe ratios of OTM puts are approximately six times

higher than the Sharpe ratio of traditional equity portfolios. These results

suggest large premiums for exposure to volatility risk. However, fully under-

standing this parameter requires going beyond examining volatility changes

1A test of the double-jump model of Duffie, Pan, and Singelton (2002) performed by Bak-shi and Cao (2003), reveals no significant difference between this model and the traditionalstochastic volatility with jump model in terms of RMSE

4

through time. It is necessary to examine this parameter in conjunction with

jumps in the price process, since these are two separate effects. Regardless

of model specification, inferring significant estimates for the parameter is a

non-trivial exercise, that requires either extensive years of data or advanced

econometric techniques.

The commodity market is quite distinct from the equity market. First,

individuals are net consumers of energy, versus net savers in the equity mar-

ket. Secondly, forward prices may be upward-bias predictors of expected spot

prices in the energy markets while the reverse is true for equities.2 Third, we

observe implied volatility skews for out-of-the money calls and in-the-money

puts; this is possibly due to firms wishing to hedge against energy market price

spikes/positive jumps. This may suggest a positive market price of volatility

risk for energy commodities. However, if forward prices are upward-bias pre-

dictors of expected spot prices, it implies a negative market price of risk for

energy products.3 A positive skew, which is a possible indicator of positive

correlation between the price and volatility process, also leads to the conclu-

sion that the market price of volatility risk is negative, as it is in the equity

markets. Nevertheless, it is not clear that the market price of risk is negative in

commodity markets, and thus the claim that there are negative Sharpe ratios

for energy commodities is debatable. Through the estimation of a negative

market price of volatility risk for the gas markets, and establishing positive

2Since the expected rate of return is typically higher for equities than the risk free rate,one expects that forward prices are downward bias predictors of expected spot prices.

3As noted by Dincerler and Ronn (2001)

5

correlation between price and volatility, strengthens the argument for negative

values for the market price of risk in commodities. In addition, I can relate

the upward-bias predictive nature in BIV by showing that it necessary to have

a negative market price of volatility risk.

Central to the estimation for the market price of volatility risk is relat-

ing the bias in Black-Scholes/Black implied volatility to the underlying data

generating process. Accomplishing estimation required recovering the risk neu-

tral parameters by linking the instantaneous volatility to thirty day BSIV/BIV

through a simulation technique. Recent literature has focused on the appro-

priate way to estimate continuous time models. Chernov and Ghysels (2002)

use the Galant and Tauchen EMM technique, Pan (2000) applied an IS-GMM

framework, and Jones (2001)and Eraker (2001) have used Bayesian analysis to

arrive at their estimates. Through a simulation within a simulation technique,

the problem of estimating the latent spot volatility from the instantaneous pro-

cesses is avoided, using 30 day Black-Scholes implied volatility as a proxy for

instantaneous spot volatility. Using these results, and implementing a mean

reverting regression framework allows inference on the level of mean-reversion,

the long run mean, and the volatility of the volatility process. The market

price of volatility risk can then be deduced from the risk neutral parameters

and the level of bias in BSIV/BIV. This procedure focuses only on the volatil-

ity process and ignores the price process, reducing the problem to one equation

and one unknown. Initially, the focus is on the market price of volatility risk,

thus I do not concern myself with the full model, and restrict attention to the

6

volatility process in estimation.

While a strong focus is placed on Black-Scholes/Black model misspec-

ification, specifically focusing on the stochastic element in volatility, it is also

important to account for the possible measurement error in implied volatility

from the model. As Hentschel (2002) points out, it is possible to find positive

upward-bias in Black-Scholes and positive skew in index options even if Black-

Scholes is correctly specified. The problem lies in inverting BS to find implied

volatility since there is potential measurement error in discrete call prices,

stock prices, dividends, risk free rate, and time to maturity. For example,

non-syncronous reporting of the closing option price and the underlying price.

These small measurement errors can cause large errors in implied volatility due

to the non-linear amplification, especially for the OTM options, and options

with time to expiration close to zero. In addition to the measurement error,

Hentschel (2002) argues the implied volatilities estimates are upward- bias due

to the absence of lower arbitrage bounds eliminating low implied volatilities.

This results in truncation, causing a smile/smirk pattern. This truncation

occurs for options away from the money, because only the true prices at these

points approach the bounds. This particular problem will be minimized for

the ATM index options since there is infrequent activity that allows the option

price to go negative. In addition, the VIX sample appears to be fairly efficient

with minimal measurement error due to the averaging of implied volatilities

from puts and calls, low weights assigned to options near expiration, and the

7

focus on near ATM options.4 Hentschel (2002) reports ATM bias of around ±

1.25% in volatility for stock index options and this bias is considerable worse

for individual stock options. This bias seems to be independent of volatility

level, assuming high enough volatility levels, and increases with a decreasing

strike price. I will account for these potential measurement errors when it

comes to estimating how biased BSIV is to realized term volatility.

As noted in Heston (1993), Hull and White (1987), and others, the

payoff of a stochastic volatility process cannot be replicated, and therefore

the market is incomplete. Under the initial assumption of perfect correlation

between the processes, I reduce the two-factor model to a single factor, and

can use the Black-Scholes model to invert the call price and arrive at the

estimate of implied volatility (BSIV). Inverting the Black-Scholes formula to

find the implied volatility may seem inconsistent when volatility is stochastic,

since constant volatility is one of the strong assumptions of Black-Scholes.

However, if at all points in time, there exists an instantaneously maturing

option, using the closed form solution to find the volatility at any specific time

would not be in violation of the Black-Scholes assumption since instantaneous

volatility is constant. Additionally, this allows for replication of any payoff

and a complete market setting. This framework allows for easy analysis to

examine the effect of the market price of volatility risk. It is important to

note that a major goal is to examine the bias in Black-Scholes, as this is the

most prevalent and tractable analytical formula we have to price options. I

4Hentschel points out a confidence interval of ± .25% in volatility.

8

will relax the assumption of perfect correlation and complete markets in both

the simulation and estimation.

1.1 Evidence on the Market Price of Volatility Risk

Since the focus of this work is the market price of volatility risk, it is

necessary to review the current knowledge on this priced risk factor. There are

two issues that must be resolved when it comes to the market price of volatility

risk. The first is the sign of the risk factor, which is less problematic than the

second, showing that the risk factor contributes to the model. For equities, the

market price of volatility risk should be negative. Options are purchased as

hedges against significant declines in the market, and buyers of the options are

willing to pay a premium for downside protection. This could be interpreted

as buying market volatility, since high volatility coincides with falling market

prices [French, Schwert and Stambaugh(1987) and Nelson (1991)]. In addition

to the high Sharpe ratios in trading option, pointed out by Bates (2000) and

Eraker (2001), Jackwerth and Rubinstein (1996) have also suggested that at

the money (ATM) implied volatilities are systematically higher than realized

volatilities which could be explained by a negative volatility risk premium.5

For gas options this issue is less clear, since the dynamics of the energy market

differ from those of equity markets. These differences are:

1. Higher market prices tend to coincide with higher volatility.

5Jackwerth and Rubinstein (1996) demonstrate this by recovering the probability distri-butions from option prices.

9

2. Beta coefficients tend to be negative for commodities markets

3. There is a significant term structure of volatility and seasonality for gas

futures prices.

Nevertheless, even in the presence of these major differences I will show

that the market price of volatility risk for the gas contracts is also negative.

The evidence on the economic impact of market price of risk is some-

what mixed. While most concede that the presence of priced stochastic volatil-

ity risk results in more expensive options, it is not necessarily clear whether

the precise parameter value can be disentangled from other risk-factors. If the

various types of jump and price risk are accounted for, does the impact of the

market price of volatility risk become insignificant? In addition, the sensitiv-

ity of the volatility of volatility process significantly impacts the ability to fit

the model which may lead to overfitting and poor out-of-sample performance.

These two parameters, the market price of volatility risk and the volatility of

volatility process, are intertwined, making inference of precise estimates of the

market price of volatility risk challenging.

Bakshi, Cao, Chen (1997) and Buraschi and Jackwerth (2001) provide

evidence that equity index options are non-redundant securities and omitting

a volatility risk premium may be inconsistent with option pricing dynamics.

Pan (2000) however, refutes this finding, suggesting that a model without

a risk factor for stochastic volatility best explains the cross-section of option

prices. She suggests that jump size risk is the major component that allows for

10

the best model fit, while the market price of volatility risk, while negative, is

insignificant. Additionally, models that do not account for jumps or jump risk,

but include stochastic volatility, severely under-price medium and long dated

options in periods of high volatility and over-price the options on low volatility

days. She notes that these models can reconcile the difference between the spot

and option markets for indicies, but the inclusion of a significant market price

of market volatility risk does not improve model fit. These results seem to be

in direct contradiction with those of Bakshi and Kapadia (2001), and Coval

and Shumway (2000).

Both Bakshi and Kapadia (2001), and Coval and Shumway (2000) per-

form non-parametric tests on option data from the S&P 500 and S&P 100.

While these tests cannot enlighten us to the value of the pricing factor itself,

they do present strong evidence for the existence of a significant parameter.

Coval and Shumway (2000) examine option pricing returns, and set up zero-

delta straddle to test for the validity of the Black-Scholes model. If the Black-

Scholes model holds, then the return on the straddle on average should be the

risk-free rate. Their findings on both the S&P 100 and S&P 500 show signif-

icant negative returns on the straddle position, generating excess returns for

the short position. This could be explained by either some jump or stochastic

volatility priced factor. They conclude that it must be the stochastic volatility

factor after constructing a crash neutral straddle,6 showing that the position

6The crash neutral straddle holds an additonal OTM put to protect against downsiderisk.

11

still produces negative returns.

Bakshi and Kapadia (2001) provide more direct evidence for the exis-

tence of a priced stochastic volatility factor by also constructing delta-neutral

position, but controlling for positive Vega. This portfolio should on average

return the risk free rate, but if it does not, this is suggestive of a significant

market price of volatility risk. Their results for a Delta-Neutral, positive Vega

portfolio, that buys calls and hedges with the stock significantly underperforms

zero. The result is decreasing for options away from the money.7 Controlling

for the strike, the underperformance is greater for longer horizons. Addition-

ally, they show that for periods of higher volatility, the underperformance is

even more negative. They account for the argument for jump premium by

showing that the risk volatility premium can still retain its explanatory power

even in the presence of higher moments. This is important as the inclusion

of a jump premium tends to account for excess skewness and kurtosis. Thus

they provide this as strong evidence for a significantly negative market price

of volatility risk.

The question arises of where the breakdown occurred between the para-

metric model of Bates (1996), Pan (2000) and others and the conclusions drawn

from the non-parametric evidence of Bakshi and Kapadia (2001) and Coval and

Shumway (2000). Could it be that the non-parametric evidence was finding

7This is potentially an interesting result since OTM puts tends to have significant jumppremiums while OTM calls tend to have very little premium according to Bates (1996). Itis worth exploring the reverse hedge to see how the portfolio performs.

12

addition jump factors that have not been controlled for in the test specifica-

tion? Or could it be that parametric model is incomplete or mis-specified. My

conclusions from the work shown in the following chapters suggest that the

latter is incorrect for both the equity and gas processes, and that the market

price of volatility risk is negative and significant.

13

Chapter 2

The Bias in Black-Scholes/Black

Implied Volatility

2.1 Introduction

The work in this chapter will address the upward-bias in Black-Scholes

and Black implied volatility. First, I will proceed with a quick review of the

stochastic volatility data generating process to provide a theoretical founda-

tion for the following empirical tests. I will then incorporate term-structure

parameters for commodities to capture the increase in volatility for close to

maturing gas futures contracts. Finally, empirical tests will be conducted

showing that Black-Scholes/Black implied volatility is an efficient but biased

predictor of future realized volatility.

2.2 The Model

2.2.1 Stochastic Volatility

The data generating process for the equity process is given below. I

have adopted the familiar square root process developed by Heston (1993):

14

dSt

St

= µ dt+ σt dzs (2.1)

dσ2t = [κ(θ − σ2

t ) + λσξσ2t ] dt+ ξσt

(ρ dzs +

√1− ρ2 dzσ

)(2.2)

In equation 2.1, the price process is a function of the drift term, µ,

volatility rate, σ, and Brownian motion dzs. The variance is a mean-reverting

process with speed of mean-reversion κ,long run mean θ, and Brownian motion

dzσ. The drift in the price-process is governed by:

µ = r + λsσt (2.3)

where r is the risk free rate and λs is the market of price of risk. The market

price of volatility risk is λσ, and ξ represents volatility of volatility. ρ captures

the correlation betweeen the processes, allowing for the Black (1976) finding

that stock returns and changes in volatility are negatively correlated. Using the

Girsanov Theorem we can see the transformation from the real world to the risk

neutral world. In the risk-neutral world µ = r, because the expected growth

rate is equal to the risk-free rate. The risk-neutral process is governed by a

separate Wiener process under the transformed Q-measure denoted dz∗, dz∗σ:

dSt

St

= r dt+ σt dz∗s (2.4)

dσ2t = κ(θ − σ2

t ) dt+ ξσt

(ρ dz∗s +

√1− ρ2 dz∗σ

)(2.5)

15

For the commodity process, the futures price F follows the process

dFt

Ft

= υ dt+ σt dzF (2.6)

dσ2t = [κ(θt − σ2

t ) + λσξσ2t ] dt+ ξσt

(ρ dzF +

√1− ρ2 dzσ

)(2.7)

where υ = λsσ. is In the risk-neutral world υ = 0, since the market price of

riskis equal to zero. Note the subscript on θt where t represents the time to

maturity of the futures contract. Thus, the risk-neutral process is:

dFt

Ft

= σt dz∗F (2.8)

dσ2t = κ(θt − σ2

t ) dt+ ξσt

(ρ dz∗F +

√1− ρ2 dz∗σ

)(2.9)

For the equity process, the market price of risk and the market price

of volatility risk appear in the real world distributions. The speed of mean

reversion and long-term volatility are assumed identical in each distribution.

Assuming that the market price of volatility risk is zero, then regardless of

changes in the other parameters, the real world and risk neutral distributions

are identical.1 As previously noted, Bakshi and Kapadia (2001) and others

have shown that the market price of volatility risk is negative, implying that in

the specification the implied volatility coming from the risk neutral distribution

would be higher than the real world volatility. However, when the market price

1The same analysis can be applied to the futures process.

16

of volatility risk is held constant, the other parameters play an important role

in quantifying the bias, and cannot be ignored.

Initially, I reduce the two-factor process by making assumptions about

the correlation between the price and volatility process, and the market prices

of risk. This was done for two reasons: First, to provide simple intuition about

relating the effect of the parameters and the subsequent difference in volatility

between the option implied volatility and the realized term volatility; secondly,

reducing the equation to a one-factor process allows for the evaluation of the

problem in simple bushy lattice framework. Assume dzs = −dzσ which implies

λs = −λσ for the equity process, discretize equation (2.1) through (2.5) and

substitute:

(St − St−1)

St−1

= µdt+ σdzs

(St − St−1)

St−1

= (r + λσt−1)4t+ [−(σ2

t − σ2t−1 − [κ(θ − σ2

t−1) + λξσ2t−1]4t)

ξ)]

combining like terms:

4SS

= [A+ λBt]4t− Ct

17

with

A = r +κθ

ξ

Bt = (σt−1 − σ2t−1)

Ct =σ2

t − σ2t−1(1− κ)

ξ

For the risk neutral process, the equations combine in a similar fashion to

4SS

= A4t − Ct, since λ = 0. Within the reduced factor process it becomes

easy to interpret the effect of an increase in λ on the change in price, and

subsequently, the volatility process. If λ is equal to zero, then we should

expect exactly the same price movements in the risk neutral process and the

real world process. However, when there is positive market price of risk, as is

the case for equities, the two processes should diverge. To evaluate the effect of

λ, I use the bushy lattice framework since the volatility is not constant. Solving

for the bushy lattice, it is easy to see the evolution of the price tree for the two

processes.2 I combine the risk neutral process with the real world process and

am left with 4S∗

S∗= 4S

S− λB4t. Since λ is positive, and σ must always be

positive, the change in the real world price must be greater than that of the

risk neutral process. From the assumption of perfect negative correlation, it

should then hold that the volatility change is more volatile for the risk neutral

process. This is easily shown by substituting equations (2.2) into (2.3), and

2Please refer to appendix for discussion on the technique used for the bushy lattice.

18

(2.4) into (2.5). The proof is shown in the Appendix. Given that the market

price of risk is positive for equities, and that dzs, dzσ are perfectly negatively

correlated, there is a resulting negative effect on the volatility change due to a

negative market price of volatility risk. This results in a less volatile process for

the objective distribution. For commodities, the same intuition applies except

that there is a negative market price of risk and perfect positive correlation

between the processes.3

If there exists a negative market price of volatiltiy risk, then result-

ing risk-neutral and real-world volatilties should demonstrate the properties

shown above for both equites and commodities. Hereto, Black-Scholes (Black)

implied volatility should be greater than realized term volatility for equities

(commodities). This can be tested by regressing Black-Scholes implied volatil-

ity (BSIV) on realized-term volatility and showing that BSIV is an upward-bias

predictor of realized-term volatiltiy.

2.3 Estimation of the Bias in BSIV/BIV

2.3.1 Data

To test the bias in BSIV/BIV, and later for the data generating process,

I use the S&P 500 and S&P 100 Index for the equity/index process and ten

years of gas futures contracts that expire in each month of the year. I have

3The assumption of perfect correlation will be relaxed in the following chapter for bothsimulation of the model and estimation of the data. For the simulation, the bushy-latticetechnique will be replaced with a quasi-Monte Carlo procedure.

19

collected daily price and annualized daily-implied volatility from October 1994

until July 2001 for the S&P 500 and from January 1st 1986 to August 26th

2002 for the S&P 100. For the gas contracts, I have futures and options prices

for all the options contracts starting with a contract that expired January 1995

and finishing with a contract that expires December 2005. I will focus on all

the contracts and will control for seasonality issues. The option and price data

has come from Bloomberg. Bloomberg constructs an implied volatility based

on a weighted average of closing prices of call and put options with time to

maturity as close to 22 days. For estimating bias I look only at ATM forward

call and put options. I will address the potential measurement error issues

shortly. The gas contracts implied volatility comes from the actual contracts,

and thus the term-structure of volatility (TSOV) must be accounted for. The

implied volatility for the S&P 100 was collected from the VIX index.4 The

daily risk free rate comes from the Federal Reserve for the 1-month T-Bill.

The frequency of the data is daily. Currently there are 1959 days for the S&P

500, 4183 days for the S&P 100, and 5067 combined days for the gas futures

contracts. Table 1 provides the descriptive statistics for the both the implied

volatility and realized term volatility5 for the S&P 100 and the S&P500. The

sample clearly indicates that implied volatility has been higher than realized

volatility for both indices as well as the pre- and post- October 1987 crash.

4The implied volatility from the VIX index was caluclated using the old methodology.The method for calculating BSIV was changed in 2003.

5Please refer to equations 3.9-3.10 for reference on the calculation of realized term volatil-ity.

20

Figure 2 shows the time series of implied volatility for both the S&P 100

and S&P 500 with daily price movements of 3% and 5%. This is shown to

highlight how infrequently the index had moved in these amounts on a daily

basis over this period. In addition, tables 3-4 document how often gas prices

have jumped in daily movements of over 5% and 10%. Table 2 has descriptive

statistics of daily returns for the natural gas futures contracts. What is evident

is the degree of volatility present in gas prices, and to what extent that these

“jumps” are clustered in certain years and monthly contracts. Controlling for

these effects will be crucial in the estimation procedure. Figure 3 shows the

daily implied volatility level for each of the gas contracts for January and July

in years 1995 and 2001, which gives the best description of the effect of the

TSOV.

2.3.1.1 Measurement Error

As Hentschel (2002) points out, the potential measurement error in

implied volatility can range from insignificant to potentially disastrous. The

problem in inferring implied volatilities from the Black-Scholes formula is that

small pricing errors in the stock price and call price can lead to large distor-

tions in the inverted volatility. The problem is relatively insignificant for the

ATM options, especially for index options, but becomes exponentially worse

for deep ITM and OTM options.6 However, since for this particular estimation

I only look at a constructed estimates of implied volatility for all contacts, the

6Refer to table 2a,b in Hentschel (2002) for example.

21

concern with measurement error is minimized. The difference between VIX

and the GLS correction in Hentschel (2002) is insignificant, and since the

Bloomberg HIVG estimate is constructed in a similar manner, I am confident

in the precision of the results.

2.3.2 Estimating the bias

2.3.2.1 Equity Bias

The hypothesis that Black-Scholes is an efficient and unbiased predictor

of realized term volatility is assessed by estimating a regression of the form

ht = α0 + αiit + εt (2.10)

where ht denotes the realized term volatility for period t and it denotes the

implied volatility from the Black-Scholes closed form solution at the beginning

of period t.7 For BSIV to be unbiased, it must be the case that α0 = 0 and

αi = 1; for efficiency the residuals should be white noise and uncorrelated

with the independent variables. As Christiansen and Prabhala (1998) note,

there could be an errors-in-variables (EIV) problem with using BSIV, and use

prior-month BSIV as an instrument. This they feel helps resolve the issue of

7ht is Christensen and Prabhala definition of realized term volatility as given in equation2 of their paper and equations 3.9 and 3.10 in this chapter. Additional specification add inpast realized term volatility such that ht = α0 + αiit + αhht−1 + εt. This was run despitethe multi-collinearity problem. The correlation between it and ht−1 for the S&P 100 wasaround .8. For the S&P 500 the correlation was close to .4. This is independent of level orlog-level specification.

22

EIV.8

In table 5, I have replicated the results in Christensen and Prabhala

(1998), with data that extend their original sample to August 2002.9 Their

findings suggested that Black-Scholes implied volatility was an efficient and

unbiased predictor of future realized volatility, as shown in equations 3.9 and

3.10. To refute the findings I need only show that the intercept coefficient not

equal zero or the slope coefficient is not unity. It is my contention that if BSIV

is an upward-biased predictor of realized term volatility, the intercept term

should be negative or the slope coefficient less than unity. The OLS regression

on the sample is done with a non-overlapping monthly frequency similar to the

Christiansen and Prabhala study. The results show the slope coefficient is less

than unity for both specifications. Additionally, the coefficient is significantly

different from one, suggesting that BSIV is an upward-bias predictor. Since

I also have data for all closing days, tests were run similar to that of Jorion

(1995) and Canina and Figelweski (1993). However, the sample has high levels

of autocorrelation and must be corrected for. The results confirm that BSIV

coefficient is significantly less than one while doing a Newey-West correction

with 22 lags. By using the entire sample I avoided any bias using any one

particular day throughout the sample.

8Please refer to their paper for a discussion of the EIV problem. However, since Black-Scholes is mis-specified, one must assume that model-misspecification is a considerable prob-lem.

9Christiansen and Prabhala also ran their specification on pre and post 1987 crash data.Their finding suggested a regime shift around the time of the crash.

23

This particular specification was done on levels of volatility versus log-

levels. In this analysis I will examine both the levels and log-levels of volatil-

ity even though log-levels seem to be more appropriate. The Christiansen

and Prabhala (1998) study also notes that implied volatility may incorporate

measurement error, and uses the prior month’s implied volatility as well as

prior month realized term volatility as an instrument.10 The results on levels

show the slope term is significantly different for one. As for the results on

the log-levels, the intercept term is negative and significantly different from

zero, suggesting upward-bias in BSIV. I find these results give foundation for

relating this bias to the underlying parameters that drive stock prices and

volatility.

I additionally looked at the S&P 500, since I wanted to confirm that

it was not index specific. This data set, while smaller, will still give enough

data points to come up with significant results. The results are shown in

table 6 and are very similar to those on the S&P 100, with the exception of

the instrumental variables test on levels and log-levels. However a joint F-

test that the intercept term is equal to zero and the slope coefficient equal

to one is 5.84, resulting in rejection of the hypothesis that BSIV is unbiased.

For the log-level, the F-Statistic is 1.87, thus I cannot reject the hypothesis.

However, the log of prior month realized volatility is significant, which also

refutes the claim that BSIV is unbiased and efficient. These results should not

10Implied Volatility may be correlated with ht, but prior month implied volatility willnot.

24

be surprising given that we know that the data cannot be described by a pure

Black-Scholes model. If there is a negative market price of volatility risk, we

should expect that Black-Scholes implied volatility is an upward-bias predictor

of future realized volatility.

When adding prior month realized volatility to the specification, I still

find implied volatility as the best predictor for future realized volatility.11 The

estimates based on prior realized volatility tend to be insignificant at either

the statistic or economic level. This is an important result. Regardless of the

bias nature in implied volatility, it still appears to be the strongest forecast of

future volatility in the market. By providing these reliable estimates on the

bias in implied volatility I provide better forecasts of future market movements

with BSIV.

Interpreting the instrumental variables test for BSIV levels of 15%,

20%, and 30% on the S&P 100 translated into realized term volatility levels of

10.41%, 13.88%, and 20.82%. For the S&P 500 these BSIV levels translate into

9.36%, 14.08%, and 23.52% for realized term volatility. It is my contention

that as the volatility in the equity markets rises, the degree to which BSIV is

an upward-bias forecast of future volatility also increases.

11Canina and Figelweski (1993) suggest that prior month realized volatility is the efficientpredictor for future realized volatility

25

2.3.2.2 Modeling of the TSOV

Solving for the bias in implied volatility for gas contracts is compli-

cated by the significant presence of a term structure of volatility. As a results,

regressing the term implied volatility on realized term volatility does not gen-

erate comparable bias estimates. Controlling for the TSOV is crucial, and will

allow for a direct comparison to the equity markets if done correctly. This

requires specific modeling of the term structure that can handle the quick

“ramping up” of volatility in the last two to three months of the contract. I

have chosen to implement several parametric candidates while assuming cer-

tain fixed controls for the volatility and TSOV parameters. The relationship

between implied term volatility and instantaneous volatility is given by

σ2T =

1

T

∫ T

0

σ2t dT (2.11)

Since there is time-dependent volatility σt = σf(t), it is necessary

to come up with a functional form to express this particular relationship.

Schwartz (1997) exponential relationship between term volatility and instan-

taneous volatility is an obvious choice, but a one factor model is limited in

it success. Thus I choose two additional forms, a quadratic and reciprocal

relationship. Adding an additional factor will capture the long run mean of

volatility, while the other factors can fit the time dynamics. Given σt = σf(t),

the options for the functional form are listed below.

26

Exponential f(t) = e−α t

Reciprocal f(t) = α+ βt

Quadratic f(t) = α+ β t+ γ t2

where t is time to maturity and α, β, and γ are TSOV parameters to

be estimated.

With daily observations for each month over a ten year span, it is neces-

sary to make certain assumptions to solve for the correct specification. I have

chosen to vary the volatility for each contract and have a fixed term structure

parameter by months to allow for yearly variations in volatility and monthly

differences for term structure controls. However, I restrict the volatility to be

constant for each day within each contract and allow the TSOV parameter

to capture the increase in volatility towards maturity. It is possible to have

chosen to let volatility vary each day of the contract while holding the volatil-

ity across contracts constant. While this will obviously improve model fit, it

diminishes the impact of the TSOV parameter, and will not reflect the true

relationship between the instantaneous volatility and 30 day estimate. The

objective function is stated below

min(α,β,γ,σt)

N∑i=1

T∑t=τ

[σ2

it −σ2

i

T − t

∫ T

t

f 2(t) dt

]2

(2.12)

where σit is implied volatility on date t and year i. σi is a year i constant

to be estimated. Equation 2.12 is minimized and in-sample fit is analyzed to

assess which model fits best. The addition of the long run factor helps with

27

overall model fit, but the results are highly dependent on the given contract

month. The exponential function form performs well relative to the others

with either fitting the close-to-maturity or far-from-maturity dates depending

on the initial condition given. The quadratic tends force the curvature to fit

the close-to-maturity dates by implying negative volatilities for the 3-7 months

to maturity period. The reciprocal fits best in certain months because it allows

for the increasing convexity close-to-maturity without sacrificing earlier dates.

Figure 4 and 5 best demonstrates this.

I test for model misspecification of the TSOV by using 5-day before,

1-day before and 5-day after volatilities for each model on each day for each

contract. These tests are typical for model misspecification as discussed in

Arimya (1980) and have been used in tests of various option models as in Bak-

shi, Cao and Chen (1997). The typical argument is that with more structural

parameters it becomes easier to fit a given model, but can cause overfitting

which will result in poor out-of-sample performance. Again minimization was

done on the objective function as given before and tests each monthly con-

tract. The results are presented in table 7 along with the in-sample results.

The results suggest that either Schwartz (1997) exponential model or the re-

ciprocal functions are the best candidates for the TSOV for gas contracts.

For each month the apparent in-sample candidate model also performs best in

the out-of-sample tests. A closer look at the January results show the perfor-

mance of the exponential model is best in all three out-of-sample tests with

the reciprocal function showing large performance improvements when using

28

5-day behind volatilities. This is suggestive of a pontential problem either

with the final couple of days of volatility in a given contract or the reciprocal

model itself. One fault in the estimation relies on the taking the log of in-

finity, which requires an approximation, and this approximation can result in

large errors when maturity of a given contract approaches. This seems to be

apparent given the results for January, where there exists a large TSOV and

poor reciprocal fit, and the results for May, which are the opposite.12

I extend the analysis by breaking up each test into individual years for a

given monthly contract and testing each model on those years. The concern is

that the results may hinge on the poor fit of one particular year thus distorting

the overall fit through the minimization of equation 2.12. For example, let year

1995 have no significant TSOV while other years have significant slopes. This

can result in a greater penalty for a given model, say the exponential, for

year 1995, while that same model fits the other years better than the other

potential parametric candidates. It may then be better to examine the years

one by one versus collectively since each year has a unique TSOV associated

with it. Below I break up the January estimation into individual years, and

examine the individual RMSE to asses the model fit. Initially it appears that

the exponential fit does best for the overall period, given the in and out-of-

sample fits. The table below suggests that the other models do better for

certain years. There is no apparent trend as the reciprocal model performs

12These particular months were choosen to shown the disparity between months that haslarge TSOV effects and months that did not. Likewise, December and April could have beenselected for this particular comparision.

29

best in years 1996, 1997 and 2001, the exponential in 1995 and 2002, and the

quadratic in the others. There appears to be a severe penalty in fitting the

reciprocal model in 1998 and 2000 as compared to the other models, which

results in an overall poor fit across all years. This evidence suggests the need

to control for the year and month effects across natural gas contracts.

TSOV Model Fit for January YearsThe table below shows the individual specification fit for the three parametric models for each yearly

January gas contract.

Year 2003 2002 2001 2000 1999 1998 1997 1996 1995

Exponential 0.3019 1.0394 8.5448 0.8985 0.3276 2.0229 1.6006 0.2097 0.2494Quadratic 0.2816 1.0778 11.2378 0.7133 0.3202 1.4206 6.4641 0.2312 0.4973Reciprocal 0.3374 2.3472 7.5101 2.1264 1.0855 4.5846 1.2225 0.1320 0.3231

2.3.2.3 Gas Bias

I am now able to extend this analysis further by examining gas futures

contracts with the necessary TSOV control. It is my belief that no one has

examined this issue in the energy markets. There are still a variety of issues

that must be dealt with when dealing with gas contracts that are not present

when dealing with an equity index. First, the data I use comes from the indi-

vidual contracts, and the options on those contracts. I have already handled

the specific term-structure issues that do not arise with the S&P, where each

data point has a specific maturity relating to it, and volatility close to matu-

rity tends to be higher than volatility far from maturity. Second, the market

is not as liquid, and there is the potential for sticky prices. This problem is

similar for the futures prices as well as the call prices, and so stickiness occurs

in both markets. Third, there are missing data points due to non-synchronous

trading in the options market. Sampling over all months through several years

30

to account for this deficiency. Additionally, since the estimation is more of a

cross-section than a time-series analysis, it does not matter how the prices

evolve, but that I have an implied volatility matched to a realized volatility

30 days or 22 trading days hence.

Estimating the degree of bias in Black (1976) implied volatility for gas

contracts involves accounting for these additional factors not present in index

options. From the prior TSOV estimation, intergrating up to a 30-day implied

volatility estimate allows for direct market comparison between the equity and

gas bias using the Christiansen and Prabhala (1998) estimate of realized term

volatility. Secondly, the impact of seasonality will require the estimation to

be done on a contract by contract basis. This is done not only to control for

monthly effects, but because the price and volatility estimates are a function

of the maturity of the contract. Unlike the S&P estimates, these estimates

are a function of the specific contract and the time to maturity. While the

TSOV control should account for the term effect, estimation on a contract

by contract basis will account for the seasonality. A fixed effects estimation

using all contracts could have been implemented, but requires specific modeling

of the variance-covariance matrix due to the high levels of cross-correlation

between the contracts. Since there are enough data points for each monthly

contract, and the individual monthly bias estimates are a foremost concern, a

fixed-effect regression is ommitted.

Given the high presence of seasonality in the energy markets I control

31

for each month of expiration for the futures contracts.13 This is accomplished

by running separate regressions for each month and accounting for the year

effects through the TSOV corrections. The results are shown in table 8. I

correct the heteroskedacity through a white correction as well as running a

weighted-least-squares using implied volatility as the weight.14 Regressions

were run using only the starting day in each month,15 and then using the full

sample with Newey-West corrected errors done at 22 day lags. This was done

for two reasons. First, the full sample cannot be used due to the high pres-

ence of auto-correlation at the daily level, and second, to have results that

were comparable to those for the equity regressions ran earlier. The findings

are quite different to those reported for the equity index regression, however,

result in the same conclusion that BIV would have to be upward-bias. What

is immediately obvious is that bias decreases as implied volatility increases.

This is not surprising since we observe the highest levels of volatility close to

maturity for these contracts. Typically, realized volatility increases as matu-

rity approaches and can even exceed implied volatility.16 However, even with

a slope coefficient greater than unity, the intercept coefficients are negative,

and significantly different from zero. For the January, July, November, and

December months, the intercept term is close to 1. A t-test on the slope coef-

13Summer and winter months tend to have more demand due to the excessive heat/cold.It is during these months that most price spikes occur.

14results suppressed.15I also ran this specification using the last day of every month, and the middle of each

month, with the results coming up similar to those reported16this can also be a function of how realized volatility is calculated. As maturity ap-

proaches, statistical variance increases.

32

ficients revealed that they were not significantly different from 1, but a joint

f-test with the intercept equal to zero was rejected.

This suggests an upward-bias in Black implied volatility (BIV) in pre-

dicting realized term volatility of gas futures contracts. We should expect that

this bias should be in the same direction as the equity market even though

the market price of risk for the energy markets tends to be negative. While

it is well documented that the price process is negatively correlated with the

volatility process for the S&P and other equity indices, this is not the case

for the energy process. As volatility increases, the price tends to increase.17

This can be seen by the positive correlation between the volatility of the gas

market and the changes in price. Additionally, it is my contention that the

market price of volatility risk is positively correlated with the market price of

risk for the energy process, and should also be negative. If this is the case, it

is can offered as an explanation for the upward-biased nature of BIV.

The table below presents the degree of bias for the monthly gas con-

tracts. There are clear cases (April, May) where realized volatility is higher

than that of implied volatility. However, these results are reflective of levels

where volatility is only observed close to maturity, and where end of month

effects are present. In these spring months volatility rarely goes above 35%,

and so it is unlikely that one would observe realized volatility above implied

volatility. June estimation from model 2 from table 8 must be interpreted

17Refer to Dincerler and Ronn for a more detailed discussion.

33

with caution because of the impact that prior month realized volatility had on

the estimate. However, the R2 from model 1 to model 2 only added 10% of

explanatory power and thus model 1 estimates may be more appropriate. By

comparison, at the 20% volatility level, the gas markets tend to exhibit greater

BSIV/BIV bias versus the equity markets, especially for the winter months.

Given that the energy markets are more volatile, and that we observe greater

BIV/BIV bias, could this tell us something about the proportional premium

placed on volatility in these markets? Should we expect that the market price

of volatility risk in the gas markets will be higher in absolute terms? A major

goal of this work is to determine this out by relating the bias to the parame-

ters that govern the volatility process. I have demonstrated the upward-bias

in BIV. This allows for testing the feasibility of various option pricing models

as well as prior estimated parameters from these models. If a model can attain

this level of bias, it further indicates the appropriateness of the specification.

Bias in BIVThe table below show the bias in BIV relative to realized term volatility. For a given level of BIV the table

shows for each month the difference between BIV and realized term volatility. Model 1 is the initialspecification given equation 2.12. Model 2 incorporates prior realized term volatility.

Model 1 Model 2

20.00% 30.00% 40.00% 20.00% 30.00% 40.00%

Jan 9.38% 7.77% 6.16% 11.90% 12.35% 12.80%Feb 11.02% 8.23% 5.44% 14.36% 15.84% 17.32%Mar 11.16% 7.84% 4.52% 11.36% 7.24% 3.12%Apr 9.80% 4.65% -0.50% 10.10% 5.05% 0.00%May 6.46% 2.29% -1.88% 6.02% 2.33% -1.36%Jun 0.42% 2.73% 5.04% 9.74% 15.96% 22.18%Jul 5.56% 4.29% 3.02% 6.96% 7.09% 7.22%

Aug 6.32% 3.73% 1.14% 4.86% 1.14% -2.58%Sep 6.40% 4.00% 1.60% 7.78% 4.02% 0.26%Oct 7.30% 4.35% 1.40% 5.80% 2.20% -1.40%Nov 6.66% 5.64% 4.62% 5.68% 3.42% 1.16%Dec 9.40% 8.60% 7.80% 12.48% 13.32% 14.16%

34

2.4 Conclusion

The implications of the findings in this section confirm two important

prior results; first, that the Black-Scholes model is misspecified, and second,

BSIV is still the efficient predictor of future realized volatiltiy. Additonally, the

results for the equities markets transfer directly to the commodities markets,

specifically for natural gas futures and the Black model. Controlling for the

term structure of volatility allows for a direct comparison between the equities

and the commodities markets, and the results reveal that both BSIV and BIV

are upward-bias predictors of σRTV .

This is highly relevant since the degree of the bias can be related to the

underlying data generating process that governs stock and futures prices. An

upward-bias in BSIV/BIV is suggestive of a negative market price of volatility

risk. The intent of the next section is to use these results and relate them

to various instantaneous structural models that incorporate both stochastic

volatility and jumps. Through Monte Carlo simulation and mean-reversion

estimation, the market price of volatiltiy risk can be extracted using the esti-

mated degree of bias found in tables 5, 6, and 8.

35

Chapter 3

Monte Carlo Simulation and Estimation of the

Market Price of Volatility Risk

3.1 Introduction

Using the knowledge attained through the upward- bias relationship be-

tween BSIV/BIV and realized-term volatility, I will calibrate the underlying

data generating process from both the risk-neutral and real-world processes

to the degree of bias using the sensitivity of the instantaneous structural pa-

rameters. The intent here is to demonstrate that the market price of volatility

risk, λσ, is negative and significant. The first will be accomplished through

Monte Carlo simulation. The second will be demonstrated by the simulations

incorporating many parameterizations, and showing that a large negative λσ is

necessary, and independent of model specification, to demonstrate the degree

of upward-bias shown in the previous chapter. Once this claim has been estab-

lished, the estimation of the market price of volatility risk will be conducted

using a stochastic volatility mean reverting framework. Using a time-series

of implied volatilities from short-term at-the-money (ATM) options and con-

structed realized-term volatilties, the market price of volatility risk can be

estimated via calibration.

36

3.2 Monte Carlo Simulation

I adopt Monte Carlo simulation to test for the sensitivity of the bias

in BSIV to realized term volatility in the underlying parameters of the model.

The stochastic volatility simulation is executed using equations (2.1)-(2.5) for

the equity process, and equations (2.6)-(2.9) for the commodity process. For

completeness, I present the real-world and risk-neutral price and volatility

processes below:1

Real-World Process:

dSt

St

= µ dt+ σt dzs (3.1)

dσ2t = [κ(θ − σ2

t ) + λσξσ2t ] dt+ ξσt

(ρ dzs +

√1− ρ2 dzσ

)(3.2)

Risk-Neutral Process:

dSt

St

= r dt+ σt dz∗s (3.3)

dσ2t = κ(θ − σ2

t ) dt+ ξσt

(ρ dz∗s +

√1− ρ2 dz∗σ

)(3.4)

where r is the risk free rate and λs is the market of price of risk. The market

price of volatility risk is λσ, and ξ represents volatility of volatility. κ is the

speed of mean-reversion, θ is the long run mean, and rho captures the corre-

lation between the price and volatility processes. dzs and dzσ are geometric

Brownian motions. dz∗s and dz∗σ are Brownian motions transformed under the

risk-neutral measure Q.

1For the futures processes, refer to the prior chapter.

37

Two variance reduction control techniques were implemented to help

reduce the standard error of the estimate and improve the efficiency of the

results.2 For each sample path, random shocks are drawn from N ∼ (0,√4t)

at 4t intervals over the life of the option. So with a 1-month to expiration

option, 22 random shocks are drawn for the price process for 22 business days.

This procedure is replicated for the volatility process and is governed by a

separate Brownian motion. Since the concern is with both the risk-neutral

and real-world processes, a total of four random draws are needed for the

evolution of one day. The option value for a call and put are then calculated

as,

Cnt = E∗t [e−rt max(SnT −K, 0)] (3.5)

Pnt = E∗t [e−rt max(−SnT +K, 0)] (3.6)

under the risk neutral measure, where n represents the particular path.

This process is repeated for 1,000,000 runs. This is slightly excessive, but, it

was important to reach an efficient estimator for the call value since inferring

the correct volatility relies on precise estimates of fractions of a cent.3 The

final call and put values are then:

2I have used the antithetic variable and control variate techniques using Black-Scholesas the know analytical solution. In addition, I have run quasi monte-carlo simulations usingthe Sobol sequence to generate results, this was done to determine the number of runs toachieve efficiency.

3As pointed out by Hentschel (2002) and others, pricing and implied volatility errors canbe large when call prices are measured inaccurately.

38

Ct =1

n

n∑i=1

Cit (3.7)

P t =1

n

n∑i=1

Pit (3.8)

By finding C, P and given the starting value for the stock price, risk-

free rate, time to expiration, and strike price, Black-Scholes, or Black for

the gas process, can be inverted and the estimate for BSIV/BIV solved. It

is important to note that the time interval for sampling the random shocks

is small, otherwise it could lead to an instantaneous shock to the volatility

process resulting in a negative variance. For current purposes, the shocks are

bound so that there are zero negative variance realizations. Nevertheless, even

without the bound the variance process infrequently dips below zero.4

To solve for the realized term volatility two methods are adopted. The

first is to sample the returns of the stock/future over the remaining life of the

option.

σrtv =

√√√√1

t

t∑i=1

(ri − rt) (3.9)

where t is number of days to expiration, ri is return on day i and rt

is the average daily return over the option’s life. Additionally, this volatility

4The large ξ is, the large the changes in variance. This can be countered by a smallersampling interval.

39

is annualize to make an easy comparison with the BSIV. This estimate of

realized volatility has been used by Christiansen and Prabhala(1998). The

second measure is

σrtv =

√∑ni=1[(ln(STi

S0)− r)2]

√T

(3.10)

where the period variance is calculated versus the daily variance within

the period. To annualize the volatility the square-root of the period was taken

versus the sampling interval. On average these two estimates should be equal.

While not reported, the bias of BSIV to either estimate of relative term volatil-

ity is not significantly different from one another, and thus only the second

estimate is reported. Calculating mean return, r, requires the transformation

from normal to log-normal.5 This requires knowledge of σ, which is unknown

prior to finding r. This is accomplished by transforming the starting normal

mean, and calculating σ2 from this initial estimate of r. From this first esti-

mate of σ2 the initial mean is then adjusted to a log-normal estimate. The

process to find σ2 with this transformed estimate of r is repeated until con-

vergence is achieved for both values, such that the σ2 is exactly the same for

the standard deviation and the log-normal adjustment for r.6

5The mean return is adjusted from µ to µ− σ2

2 .6No iteration required more than 4 loops to achieve convergence.

40

3.2.1 Stochastic Volatility Simulation

3.2.1.1 Perfect and Zero Correlation Cases

The first tests run were base cases using zero and perfect (negative for

equities) correlation. By examining the extremes in correlation it is possible

to separate out the effect of correlation and the market price of risk on the bias

in BSIV/BIV. In the zero correlation case there should be a limited skew and

minimal bias since there is no market price of volatility risk. In the perfect

negative correlation case, the positive market price of risk is transfered into a

negative market price of volatility risk in the stochastic volatility process. As

a result a greater bias in BSIV/BIV is observed as well as a difference in the

degree of bias between the ITM, ATM, and OTM options. Table 9 shows the

results .

Note the familiar skew patterns for equities and commodities when

there is perfect correlation. This is a result of the correlation and the transfer

of the market price of risk to the market price of volatility risk. When there is

no correlation there appears to be no skew and insignificant bias. The negative

bias for the OTM calls initially seemed counter intuitive given what is known

about the relationship between implied volatility and realized volatility. How-

ever, this is not surprising given the presence of perfect negative correlation.

As the stock price rises, there is an ex-ante decrease in the underlying volatil-

ity. This decrease results in lower call values and lower implied volatilities. In

real world term, traders are less inclined to extract a premium for the OTM

calls since their downside position has improved ex-ante, and can offer the

41

buyer of the option a lower price/volatility. Since the realized term volatility

is constant across strike prices, this results in a negative relationship between

the implied volatility and realized term volatility for the OTM calls and ITM

puts.

3.2.1.2 Equity

The results for the bias in BSIV for the stochastic volatility equity

process model are shown in table 11. I have separated the results into bins of

volatility levels and time to maturity. The results for the low instantaneous

volatility levels (15%), medium levels (20%), and high levels (30%), are in

Panel A, Panel B (supressed for space), and Panel C respectively. For time to

maturity I have simulated results for a 1 month,12

year, and 1 year maturing

option. Within each bin, simulations are done across moneyness, market price

of volatility risk (λσ), and ξ. Reported are only the strike/spot ratio of .9, 1,

and 1.1, λσ of 0, -.5, ξ and -2, and of .3 and .7 for equity/index process.7 The

bias for call options is reported on the first line of each segment, put option

on the second.

An examination of Panel A shows that with no market price of volatility

risk, the bias in BSIV over realized term volatility goes from 2.25% to -0.26%

from a strike/spot ratio of .9 to 1.1. This bias appears to monotonically

increase the more negative the market price of volatility risk becomes. In

7these values are similar to those reported by other authors such as Bates (1996),Pan(2002), and others.

42

fact this is true regardless of the level of volatility, moneyness, or the time

to maturity for the option contract. When λσ is held fixed, and moneyness

increases, there is a decrease in the bias. This is not a surprise since the

bias is highly related to the skewed property observable in implied volatilities

on the SPX index, and can be tied to the negative correlation between the

two processes. Also it appears that the skew mutes through time, another

property that is related to the implied volatilities on the index. For all panels,

an increase in ξ tends to exacerbate the results, especially when λσ is -2 due

to the multiplicative nature of the parameters. For example, in Panel C, the

bias increased 3.77% for ITM call at λσ of -2 when ξ is increased from .3 to

.7. Increasing this parameter has the effect of making the stochastic volatility

process more volatile, and impacts the risk-neutral process more than the real-

world process. However, this seems to have an adverse impact in that when

λσ is low, the bias becomes significantly negative, and contradicts the prior

estimation and reduces model fit.8

This negative bias for the OTM calls initially seemed counter intuitive

given what is know about the relationship between implied volatility and re-

alized volatility. However, given the results seen in the perfect negative corre-

lation case, the results of negative bias at OTM calls are potentially plausible.

As the stock price prices rises, there is an expected ex-ante decrease in the un-

derlying volatility. This decrease results in lower call values and lower implied

8A stochastic volatility model(SV) without jumps has poor model fit relative to a stochas-tic volatility model with jumps(SVJ) since it requires ξ to be high to fit short-term optionsat the expense of long dated options.

43

volatilities. In real world terms, traders are less inclined to extract a premium

for the OTM calls since their downside position has improved ex-ante, and can

offer the buyer of the option a lower price. Since the realized term volatility

is constant across strike prices, this results in a negative relationship between

the implied volatility and realized term volatility for the OTM calls and ITM

puts.

As for level of volatility, this appears to have some impact on the bias,

suggesting that there is some proportional component to the level of the bias.

Relating that back to the results in tables 5-8, this reaffirms the results for a

negative intercept term and slope coefficient close to 1 as shown in S&P 100

and the gas contracts.

It has been well documented that implied volatilities on the index dis-

play a negative skew, thus for any model to be considered viable it is necessary

to adhere to those particular characteristics. In addition, the skew should be

muted through time due to discounting, mean-reversion, and ability to recover

from crashes/spikes. However, given that this particular model has no jumps,

should we expect a skew in implied volatilities at all? Even with stochastic

volatility, does including a market price of volatility risk add anything to the

model? Figure 5 shows the skew for the SV model for a given set of parame-

ters. The simulation results appear to show that stochastic volatility, negative

correlation between the processes, and market price of volatility risk matter in

creating a skew; but does this model match the empirical data?9 Pan (2000)

9Hull and White (1987) demonstrate the volatility skew through correlation between the

44

argues that a model without jumps cannot reconcile the cross-section of op-

tion prices. I have shown that it is necessary to have a very volatile process to

create a skew, but this can adversely affect the price of the options, making

ITM options expensive or OTM options cheap depending on maturity. At

this point in time the concern is with documenting a bias between BSIV and

realized term volatility with a stochastic volatility process and significant λσ,

not with model fit. Since jumps do matter, it is necessary then to examine

the impact jumps have in the process. Additionally, it appears that stochastic

volatility with a negative market price of volatility risk is not enough to ex-

plain the full extent of the bias, given the results provided earlier in tables 5-8.

At the minimum, an ATM bias appears to be around 7%, but even with high

levels of λσ and ξ, a bias of only 5% was achieved. Increasing the magnitude of

the parameter values produced more distorted results for the ITM and OTM

options for various maturities.

3.2.1.3 Commodities

The Monte Carlo simulation for the commodity process was run on

equations 2.6-2.9. Since the concern here is with the valuation of an option on

the price of a future, Black’s formula is implemented to determine the implied

volatility of the option. Similar to that for the equity process, results are

generated using similar underlying parameters. The correlation between price

and volatility process and the market price of risk are opposite of those of the

processes

45

equity process.

Given the negative market price of risk and positive correlation, the

results show an upward bias in BIV, but with a positive skew versus a negative

skew. For the ATM options, a bias in BIV of 1% to 5% is observed dependent

on level of volatility, ξ, and the market price of volatility risk. The strongest

bias is noted at the highest levels of volatility (40%), ξ (.7), and market price

of volatility risk (-2). This conforms to the early results on the gas data,

given the expection that the bias is dependent upon level volatility present.

The results for the ATM options for the other levels of the parameters show

much more consistency across the different levels of volatility. There are three

potential explanations for these results. First, the regression results earlier

are picking up specific characteristics of the gas contracts not modeled in the

generic framework. Second, the model is incomplete. Third, the parameter

estimates are inconsistent with plausible estimates. I will address the first

two issues when introducing jumps and alternative models. The third can be

handled by looking at the ITM and OTM results for the same simulation.

As noted by Pan (2000), when ξ is increased it can cause severe mis-

pricing of ITM and OTM options for medium to long maturities. This is the

basic flaw of the non-jump stochastic volatility models; that to fit the short-

term data it is necessary to have a large ξ which can cause pricing error for

longer maturities. Table 12 shows the percent bias for a 1 month option with

a market price of volatility risk of -2 and -0.5, and ξ of .3 and .7. When there

is a small market price of volatility risk and a high level of ξ, the bias found is

46

negative for some ITM calls and OTM puts, which results in a cheap option

price. When this ξ is combined with a market price of volatility risk of -2,

the ITM calls and OTM puts are too expensive; the bias is around 8% for

the 6 month deep-ITM call, and approximately 10% for the 1 year deep-ITM

call.10 This bias is too high to match the actual data, suggesting that some

parameter values are too high. In the case of -.5 market price of volatility

risk, there is a negative bias, which again is unrealistic. It is likely that the

model will need to incorporate jumps to capture the full empirical properties

of the data. Adding jumps may resolve the model fit through time, and avoids

an excessive ξ, but it is unlikely that it would warrant a zero market price of

volatility risk, as Pan (2000) claims.

3.2.2 Jump Model Simulation

Up until this point I have only addressed the bias when stochastic

volatility is present. It is important to examine the impact of jumps on the

bias, both with stochastic volatility and without. I have chosen to model the

jump process in two ways. The first is to incorporate a market price of jump

intensity with a constant jump size. The focus here is on the intensity of the

arrival versus the jump size since defining a jump in prices is not rudimentary.

Bates (1996) for example, finds a jump size of 1.5%, while Pan (2000) finds

jumps size of 1%. It is hard to argue that a 1% movement in stock price in any

one day constitutes a “jump”. An examination of figure 2 shows the arrival

10results supressed

47

of 3% or greater and 5% or greater jumps in price for the S&P 100. Only

once has the index experienced a jump of over 10% in one day in the sample.

Secondly, it may be tough to distinguish between jump sizes in the real-world

from jump sizes in the risk-neutral since this is not directly observable.

The alternative is to model both the jump size risk as well as the

jump intensity risk. The jump size risk is modeled similar to Pan (2000). I

also choose to model the jumps and the intensity proportional to the level

of volatility. A Probit test was done on the frequency and size of the jump

relative to volatility levels.11 The test reveals there is a positive and significant

relationship between jump size and frequency of the jumps on volatility level.

The independent variable chosen was start of the month volatility, and then

was sampled over the next twenty two days for jump frequency and jump size.

This was done to distinguish that volatility level was affecting jump frequency

and size, and not vice-versa. I selected daily price movements of 3% and 5% to

signify a jump in the index and tested the relationship with an ordered Probit.

Results reveal t-stats of 2.49 and 6.17 for absolute value changes. Positive

and negative movements of 3% were also tested, resulting in 4.93 and 5.30 t-

stats respectively. An OLS regression was performed with corrected standard

errors for jump size on volatility level. The absolute values of the magnitude

of the price movements above 3% were summed within the 22 period, as well

as looking at just positive and negative jumps. The t-stats were 4.41, 4.77,

and 3.66 respectively. The coefficient on the negative jump size regression is

11Table supressed

48

negative because the price movement itself was negative, corresponding to a

higher level on implied volatility. These results lend credibility to modeling

the jump proportional to the underlying volatility/variance level.

For the simulation the jumps will be drawn from a N ∼ (µ∗, σ2) for the

risk-neutral distribution and N ∼ (µ, σ2) for the real-world distribution and

arrive at a rate γ. Within this specification, the jump size and arrival rate

have been modeled proportional to volatility. The simulation will test both

a proportional jump model and pure jump model, one where jump size and

arrival rate are state-independent. For the simulation, the jump parameters

will be inputs to the model to asses the impact of the market price of jump

size and intensity risk. The real-world and risk-neutral price and volatility

process for equities are given below:

Real-World Process:

dSt = [r + λsσt + γσt(1− λj)(µj − µ∗j)]St dt (3.11)

+σtSt dzs + dzj − µjσtStγ dt

dσ2t = [κ(θ − σ2

t ) + λσξσ2t ] dt+ ξσt

(ρ dzs +

√1− ρ2 dzσ

)(3.12)

Risk-Neutral Process:

dSt = rSt dt+ σSt dz∗s + dz∗j − µ∗jσtStγ dt (3.13)

dσ2t = [κ(θ − σ2

t )] dt+ ξσt

(ρ dz∗s +

√1− ρ2 dz∗σ

)(3.14)

where

49

1. λs, λσ, λj, and (µj − µ∗j), are the market price of risk, market price of

volatility risk, market price of jump intensity risk, and market price of

jump size risk respectively. Jump intensity and size risk are proportional

to volatility.

2. ρ is the correlation between the price and volatility processes

3. dzj, γ, and µj are the jump process, the jump intensity (arrival rate),

and the jump size respectively.

3.2.2.1 Results of Pure Jump Model-Equity

The results of the pure jump process (non-proportional to volatility)

with and without stochastic volatility are shown in table 13. In this particular

case the jump size is fixed to a -10% price movement in any one day, with the

underlying spot volatility at 30%. Choosing a -10% possible daily movement

arriving at least once a year was picked to overstate the possible effects of

jumps since the concern is not directly with the jumps, but that the market

price of volatility risk is an important factor even in the presence of jumps.

When simulating with stochastic volatility and jumps, the market price of

volatility risk equal to zero. The γ (jump intensity) and the market price of

jump intensity risk were varied over a range of strike prices. Panel A shows

the results for the call implied volatility and Panel B shows the put implied

volatility.

Increasing γ from .5 to 1, which is equivalent to experiencing a jump

50

once every other year to once a year, should cause an increase in the bias of

both the put and call options. It is not surprising that the increase in gamma

impacts the bias most significantly with the ITM options and when the jump

intensity is highest. The bias goes from 1.42% to 2.56% for an increase of

1.14%. It seems intuitive that when the market price of jump intensity risk is

adjusted, the bias is also impacted. By increasing the market price of jump

intensity risk the likelihood that the price would experience a jump in the

risk-neutral world elevated versus the real-world. This exacerbates the bias

since the price experiences higher volatility through a jump in price in the

risk-neutral world, and results in a higher option value. This holds true even

more so for ITM options, and results in the observable downward sloping skew

due to the increased bias in BSIV.

Introducing a stochastic volatility process intensified the bias even with-

out the presence of a market price of volatility risk. This is not a revelation

given the prior results. The current level of volatility can affect the bias, with

higher spot volatility having a higher degree of bias. As spot volatility in-

creased, higher levels of bias are observable relative to no stochastic volatility

present. For example, call options with a γ of 1 and a strike/spot price of .9,

have an increase in the bias of 1.19%, 1.16%, and 1.09% across values of .2,

.5, and .9 for market prices of jump intensity risk when stochastic volatility is

included. However, a pure-jump process with and without stochastic volatility

but no market price of volatility risk is not enough to explain the bias found

in tables 5-8. In fact the results are less convincing compared to those found

51

with the stochastic volatility model with no jumps but a negative market price

of risk

3.2.2.2 Results of Pure Jump Model-Commodities

Again, the starting values for the parameter were identical to those of

the equity process, except for the market price of risk, correlation between

the two processes, and jumps. Given the positive correlation between the two

processes, we should expect a transposition of the bias around the ATM option

for commodities options. While this is evident from the results in table 15, it

again appears that the exclusion of a price volatility factor cannot reconcile

the empirical magnitude of the difference between realized term volatility and

BIV. The jump parameters were again fixed at 10% jump on any given day, but

this time a jump resulted in a price spike versus a price crash. The standard

deviation of the jump for both the risk neutral jump and real world jump was

set a 3.25%. Panel A shows the jump process without stochastic volatility,

Panel B is with stochastic volatility but with zero market price of volatility

risk, While including stochastic volatility does impact the bias, especially for

the OTM calls and the ITM puts, it does not have enough of a significant

impact to be considered different from the model without stochastic volatility.

When γ and priced jump intensity risk increase, the bias also increases.

This is similar to the results for the equity process. However, to achieve the 7%

to 8.5% bias shown earlier, it would be necessary to distort these parameters

beyond reasonable limits for the S&P. A γ of 1 translates to experiencing one

52

crash/spike per year. Only once has the S&P 500 or the S&P 100 experienced

a one day crash of over 10%, so to assume that this would occur once a year is

potentially unreasonable. For the commodities markets, this assumption may

be relaxed, since in recent years major price spikes occur yearly, especially in

high peak months. It would also not be surprising to see one day movements

in excess of 10%, so to compensate additional tests were ran for higher levels

of gamma, jump size, and priced jump risk intensity.

I have increased experiencing a jump up to 5 times a year, having a

jump size of fifty percent, and altered the market price of jump intensity risk

to 3. Increasing these effects alone is not enough to establish a strong enough

bias in BIV to realized term volatility. The increase in γ affects the bias

significantly, especially when increased to 5. However, when all the parameters

are increased together, a bias around 8% is achieved when γ is 2, jump size

is 20%, and the market price of jump intensity risk is 3. This again seems

unjust, even for the more volatile commodity contracts. The most movement

any one contract experienced was February 1997 when the contract had a one

day movement of 17% with 15 days to expiration, experienced 2 days with

jumps greater than 10%, and had a volatility12 around 40%. Even given these

actual values, it is tough to claim that these prior parameter values are just.

12standard deviation of daily price movements

53

3.2.2.3 Results of Proportional Jump Model- Equity

Table 14 shows the results for the proportional jump model. Similar

to the fixed jump size model, tests were done on proportional jump diffusion

models with and without stochastic volatility. Again, I test with underlying

spot volatility of 30%, but now the jump size is random. µ∗ is set equal to

-10% and σ2 to 3.25%. For the real world jump µ is set equal to -1%. These

parameters estimates are similar to those of Pan (2000). Since it is not a major

focus, I have not adjusted the degree of the implicit market price of jump size

risk, and kept these parameters fixed throughout the simulation.

It appears that adjusting for a proportional jump and introducing ran-

domness in the jumps causes more intuitively pleasing results. First, as γ

increased the bias in BSIV increased in both the call and the put. Second,

there is only positive bias, and as strike price increased, the bias tended to-

wards zero versus becoming negative as in the models without jumps. Third,

as the market price of jump intensity risk increased there was a resulting in-

crease in the bias, although the impact of the jump intensity decreased the

greater the call (put) is out-of-the money (in-the-money). This is analogous

to the skew property observable in implied volatility. When adding stochastic

volatility there was an observable statistical increase in the bias at a γ of 1.13

While more asthetically pleasing, there appears little improvement over the

pure jump model in terms of explaining the bias in BSIV. This model is simi-

13The bias increase is .97%, 1.15%, and 1.15%. Tests reveal no significant differencebetween BSIV bias between the pure jump diffusion and proportional jump diffusion models.

54

lar to the one in Pan (2000), and although she assesses that this model fits the

data best, it clearly cannot explain the degree of bias found in Black-Scholes.

Given this finding it would appear that a negative market price of volatility

risk in combination with a jump process could rectify the discrepency.

3.2.2.4 Results of Proportional Jump Model-Commodities

The proportional jump model provided similar results to those from

the pure jump model, with the major exception coming with a higher degree

of bias for the OTM calls and the ITM money puts. Again, I tested the effect

of higher γ, jump size, and jump intensity risk for the commodity process with

this model. An additional consideration had to be taken for jump size risk, as

well as the volatility of the jump size. The results are shown in table 16.

Increasing γ, jump size, and the market price of jump intensity risk

has similar magnitude effects on the bias as in the pure jump model. When

adjusted for the volatility of the jump, and the implicit jump size risk, the

impact was negligible on the bias. However, what was surprising was the

combined increase of the parameters simultaneously resulted in significantly

less magnitude bias as compared to the pure jump model. When γ was 3, jump

size was 20%, and market price of jump risk was 3, the bias was approximately

5% in the proportional jump model as compared to 8% in pure jump model.

Only when combined with higher jump size volatility did the bias approach

8%. This suggests a need for the market price of volatility risk to reconcile

the results given the infeasibility of such parameter values.

55

3.2.2.5 Results of Jump Models with Negative Market Price ofVolatility Risk- Equity

For comparison I now test the exact same models but include a neg-

ative market price of volatility risk. The inclusion of this parameter should

improve upon replicating the findings of an empirical upward bias in BSIV.

The other parameters will be identical to the prior simulations, except for the

market price of jump risk as well as the time to maturity. The results for this

simulation can be seen in table 10.

An examination for the ATM options of 1 month maturity and -.5

market price of volatility risk reveals a bias of 1.33% and 1.85% for a 0.5

and 0.8 market price of jump risk. This suggests that an increase in jump

intensity risk amplified the bias while the market price of volatility risk was

held constant. When I increase the market price of volatility risk from -.5

to -2., the bias almost doubles to 2.72% and 3.29%. This particular effect

is magnified when the time to maturity lengthens, as the bias increased an

additional 2%. However, when the market price of volatility risk is -.5, the

bias diminishes drastically, and even becomes negative for one year options.

This further suggests a highly negative market price of volatility risk. For

this particular simulation I choose to only vary the results over these given

parameters. For the gas process, I altered ξ, since this parameter in conjuction

with λσ contributes the most significant effect on the bias in BSIV.

56

3.2.2.6 Results of Jump Models with Negative Market Price ofVolatility Risk- Commodities

For the pure jump model with stochastic volatility I initially ran simu-

lation for just the ATM options for a variety of different volatility levels. The

parameters were adjusted to establish sensitivity of the bias to each parameter,

and to confirm at what values of the parameters a bias of approximately 8%

can be achieved. It was necessary to find a bias close to 8%, since the results

in section 3 suggest this. Generating an 8% bias can be achieved through high

levels of market price of volatility risk, ξ, gamma, and/or jump size. Some lev-

els of the parameters will be considered infeasible, but a realistic combination

of increase can provide the results. These results are shown in table 17.

The expectation is that the bias should be relatively stable for different

levels of volatility. However, there should still be expected minor increases in

this bias when volatility moves from 20% to 40%. When a market price of

volatility risk of -4 is used, and other parameters are slightly altered, a bias

of 8.7% is attained at a mean volatility level of 30%. This bias deviates about

1% for a volatility level decrease of 10%. If we believe that these parameters

are fair values for their real counterparts, it is still necessary to examine the

performance of the ITM and OTM puts and calls, as well as the performance of

the model at longer maturity levels. The ITM calls show a small degree of bias,

with deep ITM calls (strike-to-spot of less than .9) with a bias of no greater

than 4% and falling. This bias is approaching zero the further in the money,

57

which is what should be expected.14 The results for longer maturities show the

upward bias that we have come to expect, along with the muted skew. For a

strike-to-spot ratio of .9, BSIV is approximately 3.3% above the spot volatility,

and 13% above the realized term volatility. While the simulation divulges

nothing about model fit, it has revealed information to the appropriateness of

the parameters that govern the data generating process. Figure 1 demonstrates

the positive skew for commodities for the four parametric models simulated

and bias in BSIV that each generated.

3.2.3 Results of Prior Parameter Estimates

The literature is fairly extensive when it comes to the work done on

index options. Multiple works have address estimation techniques, alternative

models, and parameter evaluation. I address these prior works by examining

their parameter estimations to see if they 1st) can achieve appropriate level

of upward bias in the Black-Scholes implied volatility as compared to realized

term volatility, and 2nd) whether their parameter values can be considered rea-

sonable. The issue is addressed by examining three separate models with differ-

ent estimation techniques. Pan’s(2000) model is the traditional Bates(1996)

model with two-factor geometric proportional jump diffusion. Eraker(2001)

uses a similar setup with a two-factor geometric pure jump setup. Finally

14The results with different spot volatility levels can be provided upon request. Theresults are similar to those tested at a spot volatility level of 30%. Additional tests wererun using a spot volatility of 20% and 40% for the gas process with a variety of maturitylengths.

58

I examine Jones(2001) GAM2 model, which is an extension of the constant

elasticity of variance model. By examining these models is in no way a com-

prehensive examination of the literature. Many extensions have been proposed

to the existing model such as jumps in volatility, two volatility factors, and

factors for crash risk.15 For each model, simulation over the parameters from

their estimation was done for a ATM 1 month to maturity option. Implied

volatilities were inferred by inverting Black-Scholes and calculating realized

term volatility from equation 3.9. The table below summarizes the bias found

through the simulation and the value for the market price of volatility risk

each author found from their estimation.

Pan(2001), Eraker(2001), Jones (2001)The SV model refers to a model with only a stochastic volatility process with a market price of volatilityrisk; the SV0 has no market price of volatility risk. The SVJ models include jumps in the price process.

The GAM2 model is an extension of the constant elasticity of variance model.

Model λσ λσξ Bias

Pan-SV -7.6 -2.43 2.84%Pan-SV0 0 0 0.41%Pan-SVJ -3.1 -.93 0.35%Pan-SVJ0 0 0 -1.45%Eraker-SV -2.52 -.5544 1.81%Eraker-SVJ -2.28 -.4604 0.23%Jones-GAM2 8.45 -68.93 3.86%

The results above suggest two possible explanations. First, that one or

none of the models are capturing the dynamics of price and volatility evolution.

Second, the estimation techniques are not fully encompassing the data, and

15for further discussion of the these models refer to Bates(2000), Bates(2002), and Er-aker(2001).

59

arrive at distorted parameter estimates. While it appears that the higher in

terms of absolute value the market price of volatility risk is, the higher the bias

becomes, this effect diminishes when jump parameters are included. A direct

relationship between market price of volatility risk and the bias in BSIV can

not be made without examining the effect of the other parameters, especially

ξ. Since λσ and ξ are multiplicative in the volatility process, it is important

to examine the combined effect of the two values on the bias. As the above

table shows, all the values are less than or equal to zero, and are negatively

correlated with the positive bias. In fact, Pan’s SVJ0 model, which has the

best model fit, produces a negative bias with a zero market price of volatility

risk, further suggesting the importance of the parameter.

The best candidates above based solely on the bias results appear to

be Jones GAM2, Pan-SV, and Eraker SVJ model. However, as noted by the

authors these models underperform when it comes to model fit as compared

to the SVJ model. Jones’ model does not incorporate any jumps, and his ξ

parameter seems to be to high as compared with previous results. The prior

simulation shows that using the traditional Bates model as a framework, one

can input appropriate parameters and arrive at the desired results. So, the

question arises to where the breakdown in estimation came from in arriving

at implausible parameters in fitting the model.

60

3.3 Estimation

3.3.1 Simulation within a Simulation

There has been much space devoted recently in the literature to empir-

ically testing the feasibility of these parametric models. The main issue faced

is recovering the latent spot volatility, which precludes the possibility of writ-

ing a likelihood function. Some authors such as Chernov and Ghysels (2002)

have implemented Galant and Tauchen EMM (1998) methodology, while Pan

(2000) applied “implied-state” GMM to estimate the parameters, and Jones

(2001) used a Bayesian approach. I adopt a different philosophy. Since the

intent differs from prior studies, I will use the historical BSIV and a proxy for

realized term volatility in the estimation procedure. To verify that I can link

these two estimates to the original underlying process, I generate the results

through a multi-simulation procedure.

Both the risk-neutral and real-world processes should have the same

instantaneous spot volatility, but the 1 month estimates of volatility should be

distinct for the two processes due to the various risk factors. Thus any 30 day

estimate of true Black-Scholes implied volatility should contain information

regarding the magnitude and direction of the jump size, jump intensity, and

market price of volatility risk factors. However, to attain these estimates it is

necessary to establish a link from the 30 day estimates to the original instan-

taneous κ, θ, and ξ. Additionally, the real-world volatility can be recovered if

the original instantaneous spot volatility is known.

To accomplish this I simulate the underlying model through time, start-

61

ing at point t = 0, while additionally simulating 30-day option paths at each

point in time (t = 1, ....n). This generates a time series of option prices as

well as a time series of the underlying volatility. Generating the instantaneous

volatility time series is essential as that allows me to decipher the market

price of volatility risk. After establishing a link between instantaneous volatil-

ity and BSIV a mean-reverting regression framework is used to estimate the

risk-neutral process with the simulated implied variances.

For the equities the transformation of the volatility process into discrete

time intervals is below:

dσ2 = κ(θ − σ2

)dt+ ξσ dz∗ (3.15)

σ2t − σ2

t−1 = κ(θ − σ2t−1)4t+ ε (3.16)

4σ2 = a+ bσ2t (3.17)

with a = κθ4t and b = −κ4t. For the real-world process, the same

instantaneous spot volatility is used. It is important to recover the instanta-

neous volatility within the mean-reverting framework. While the setup is the

same, b = −(κ − λσξ)4t should contain the market price of volatility risk.

If the market price of volatility risk is zero, then the coefficient estimates a,b

should be the same. If there is a negative market price of risk, the expectation

is to observe a more negative coefficient for the slope in the risk-neutral esti-

mation than in the real-world. Dividing a by −b will recover θ if the market

price of risk is zero. When it is not, this requires adjusting the estimates by 4t

to infer the values since simple division will not reveal appropriate estimates.

62

For the gas process the transformation is slightly different due to the

time dependency in θ and the functional form placed on the TSOV. Choos-

ing the reciprocal specification for the TSOV results in the conversion from

continuous to discrete as

dσ2 = κ(θ − σ2

)dt+ ξσ dz∗ (3.18)

θt = α+1

t2θ (3.19)

σ2t − σ2

t−1 = κ(θt − σ2t−1)4t+ ε (3.20)

4σ2 = b0 + b11

t2+ b2σ

2t (3.21)

with b0 = κα4t, b1 = κθ4t and b2 = −κ4t.

To test the feasibility of the simulation within a simulation, regres-

sions were run on the resulting experiments with and without market prices

of volatility risk. The intent here was to retrieve the instantaneous parame-

ters initially entered into the simulation. Noting that instantaneous volatility

changes over time requires extensive simulations through time so as not to bias

the results either up or down. In addition, throughout the tests there were no

shocks to the system with drastic price movements since the goal is to only

recover the speed of mean reversion, the long run instantaneous mean, and of

course, any market price of volatility risk. Later I will account for jumps, and

the various market prices of jump risk.

63

The initial test had no market price of volatility risk; the intent here

was to show that the recovered instantaneous volatility was the same as the

implied volatility from inverting Black-Scholes from call and put prices. I

am at present ignoring the potential arbitrage opportunity by forcing a zero

market price of volatility risk since the goal is to show the validity in the

simulation within a simulation technique. The second regression is the result

of a -2 value for the market price of volatility risk. All other parameters are

the same.

Table 18 shows the results of the mean reversion regression. By divid-

ing the coefficients in the regression κ, θ, and the market price of volatility

risk was recovered. For a process with no market price of volatility risk t-tests

revealed that the BSIV from the 30-day option was not significantly different

as the underlying spot volatility even though the instantaneous spot volatility

is allowed to move on a daily basis. This is important since 30-day implied

volatility can be used as a proxy for the instantaneous spot volatility. When

there is a market price of volatility risk, the resulting slope coefficient is lower.

Given that the κ is 5.61, I can infer the type of effect that the market price of

risk has had on the resulting coefficient. Since finding the parameters through

simple division is not feasible, the ratio between the slope coefficients is ex-

amined for instances of the existence and absence of market price of volatility

risk. The resulting ratio is 1.62. From this value calibrating the model backed

out what value the market price of volatility risk had to be. T-tests revealed

that the value was not significantly different from -2 for the market price of

64

volatility risk given the other initial values in the estimation. What is also

observable is that recovered θ is the same for both processes, which is essen-

tial since the given instantaneous spot volatility is same for both simulations

even with different market prices of volatility risks. The given values in the

simulations were κ = 5.61, θ = 17.5%, ξ = .3, and ρ = −.53. The starting

stock price and strike price were set equal to 50 with a 4% risk free rate.

3.3.2 Estimation Using Mean Reverting Framework

Using the data described in section 2.2.1, and the mean reverting tech-

nique described earlier, I regressed the 30 day implied volatility series of the

S&P 100, S&P 500, and the gas contracts. For the S&P 100 the data was

split into pre- and post- October 87 crash samples. For the gas contracts it

was necessary to separate the contracts into individual months in the mean-

reverting framework to remove any seasonality effects. It was also necessary

to include year dummies, as there is a clear year effect for each contract. The

results are reported in tables 19 and 20.

Most of the slope and intercept coefficient are significant for the S&P

100, S&P 500 and each of the monthly gas contracts. Translating this into

actual values, multiplying b by 252, κ would be about 50.85 for the S&P 100

and 14.67 for the S&P 500. While 50.85 appears to be slightly high, it does

include the crash of October 87. The separate pre- and post- crash samples

have κ of 9.42 and 16.11 which appear more reasonable and highlight the

increased volatility present in the market post the October 87 crash. For the

65

gas contracts there is a much lower level of mean-reversion due to the presence

of the TSOV for all months. Months such as January that tend have very

large TSOV parameter estimates will result in smaller κ estimates since the

TSOV parameter is capturing the large ramping up of volatility.

The long run mean, θ, can be inferred by −ab. This results in an average

volatility of around 22.62% for the S&P 500 and 19.52% for the S&P 100. For

the gas contracts θ is equal to − b1b2

. It is apparent that the winter months

have much higher levels of volatility while the other months have volatility

levels similar to that of the S&P indices. This is quite intuitive given the

high demand for heating in these months. Solving for ξ is simply a matter

of examining the sum of squared errors from the regression, and adjusting

for the time and volatility factors. The values for ξ may be considered high

as compared to other models, but not accounting for jumps forces the model

to elevate ξ for better fit. Since there is no frame of reference for the gas

markets, equity values are used and could not be considered improper given

the similarity. Given these values, and relating them to the instantaneous

counterparts is all that remains is estimating λσ.

3.3.3 Estimation of λσ

Running regressions on the simulation within a simulation revealed that

the instantaneous underlying parameters were recovered from the 30 day im-

plied volatility estimates. This allows the use of the 30 day implied volatility

as a proxy for the latent instantaneous volatility. While observing that 30

66

day implied volatility does not equal instantaneous volatility, it can be used

as a legitimate proxy given the numerical evidence shown in the simulation

with a simulation. However, I was unable to recover the same parameters using

the realized volatility even given the market price of volatility risk adjustment.

This presented a problem in estimating the market price of volatility risk since

the instantaneous volatility is needed for both processes. This problem is cir-

cumvented by using the knowledge of the biased nature of implied volatility

as a predictor of future realized volatility. Given the estimations done earlier,

there is a proportional bias of around 73.5%. Using the estimates from the

mean-reversion regression done on 30-day implied volatility and the propor-

tional bias, the market price of volatility risk is recovered through calibration.

In addition, the actual bias for any particular time period can be used, i.e. the

pre-Oct 87 crash BSIV bias levels to find a λσ for that period. This generates

a time-series of λσ, which in turn generates appropriate significance for the

estimates.

This same process is replicated for the gas contracts, but with the

added complication of the TSOV. I adjust the mean-reversion regression by

incorporating the time component for theta. Substituting in for θ eliminates

the intercept term and results in two time dependent regressors. However, the

added complication of contract specific volatilities requires separating each

contract by month to find unique parameters for each monthly contract. The

steps in the estimation are outlined below

1. Divide the sample into non-overlapping intervals

67

2. Run variance regressions to obtain κ, θ, and ξ for each sub period

3. Calculate bias between implied volatility and realized volatility for that

period using either a) the results from bias regression earlier or b) actual

data from that period

4. Using known parameters and bias in BSIV/BIV, calibrate model to find

λσ

5. Compute mean and standard deviation for λσ to obtain significance

While the calibration method in backing out lambda achieves reason-

able estimates, it is necessary to gather some measure of statistical significance

for these measures. By estimating multiple lambda’s within sub-samples al-

lows me to generate confidence intervals for the parameter. To account for

overlapping estimation periods, adjustments for correlations were made by

using the number of days in common. The correlation is modeled as such

Let

Xi ∼ N(µ, σ2)

Corr(Xi, Xj) =

{kn, if k > 0

0, if k = 0

where n is the number of days over which λσ are estimated and k is

the number of days in common. Now consider the traditional estimator of

variance given by

68

s2 =1

(n− 1)

∑i

(xi − x̄)2 =1

(n− 1)

∑i

e2i (3.22)

Taking expectations of s2 yields

E(s2) =1

(n− 1)

∑i

e2i =1

(n− 1)E(∑

i

e2i )

=1

(n− 1)[∑

E(e2i ) + 2∑

i

∑j>i

E(eiej)]

=1

(n− 1)[nσ2 + 2

∑i

∑j>i

Cov(eiej)]

=1

(n− 1)[nσ2 + 2

∑i

∑j>i

ρijσ2]

=σ2

(n− 1)[n+ 2

∑i

∑j>i

ρij]

An unbiased estimator of σ2 in the presence of correlation is given by

σ2 = s2 ∗ (n− 1)[n+ 2∑

i

∑j>i

ρij] (3.23)

To control for heteroskedacity λσ was weighted by the inverse of ξ since

ξ role in the volatility process and the estimation of λσ are intertwined. The

greater ξ is the more distortion in the λσ estimate, and thus weighting the λσ

by the inverse of ξ helps with overall precision. Using the inverse of ξ to weight

λσ also adds to the precision due to distortion in ξ caused by the absence of

69

jump parameters. When ξ is large, there is greater probability that it has been

mismeasured due to the exclusion of any potential jumps in the model.

The estimates for the monthly λσ are below. For the S&P 500/S&P

100 the lambda’s are negative and statistically significant. The S&P 100 has

a higher overall bias based on a longer time set that involved the October 87

crash and prior. This period has been documented with very expensive out

of the money puts suggesting a larger market price of volatility risk as well as

larger jump premiums. Each monthly gas contract’s λσ are negative and are

significant at the 5% level. The winter months tend to have higher lambda’s

than the other months which follows the typical seasonality patterns that the

winter months are more volatile, experience more jumps, and tend to have a

higher degree of bias in implied volatility. These Sharpe ratios are relativly

high, and must be interpreted with caution. While authors such as Bates

(2000) and Bakshi and Kapadia (2002) document the significant premium

extracted from selling option, the results in the table below do not account

for jump premiums. The premiums are slightly inflated since the model has

to account for large daily price movements by increasing ξ. Typically when

fitting a stochastic volatility model without jumps ξ will be higher due to the

excess kurtosis in option prices. This results in distorted λσ. However, while

not concerned with option model fit at this moment, just including stochastic

volatility can improve model fit by almost 70% over the Black-Scholes model.

In addition, since I am only looking at ATM options, and the most significant

jump premiums occur for ITM (OTM) calls (puts) for equities and OTM calls

70

for commodities, I conclude that these estimates cannot be too far from the

truth.

Estimated λσ

Estimated λσ from calibration of model from sub-period estimation of κ, θ and ξ. The bias level isestimated for each sub-period and λσ is back-out from the monte carlo simulation. The gas contracts have

been corrected for overlapping correlation and each estimated has been weighted by the inverse of ξ

Equity:S&P S&P100 500

λσ -7.98 -5.93Stdev (2.23) (3.91)

Gas:Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

λσ -7.03 -8.77 -6.59 -5.14 -6.13 -6.79 -4.50 -5.06 -4.66 -3.46 -4.38 -4.09Stdev (2.49) (3.29) (2.37) (2.14) (2.72) (2.59) (1.68) (2.09) (2.39) (1.83) (1.75) (1.51)

3.4 Conclusion

I have examined within a stochastic volatility environment the extent

to which BSIV/BIV is a biased predictor of realized term volatility. By us-

ing Monte Carlo simulation with variance reduction techniques to reduce the

standard errors I was able to extract the effect of the underlying parameters

governing the data generating process. By controlling such variables as cor-

relation between the process, underlying volatility, and jump size, inferences

were made on the sensitivity each parameter had on the bias. Additionally,

it was observed that the market price of volatility risk was influential even in

the presence of a jump process. This is clearly an important finding since this

had not been explicitly stated in the literature.

Beyond looking at the equity process, I have touched upon how the

market price of volatility risk affects the bias in BIV for commodities. Given

the market price of risk is typically negative in the energy markets, and that

71

prices and volatility tend to be positively correlated, I have found that the

market price of volatility risk for natural gas contracts is also negative. The

direction of the bias in BIV on realized term volatility is also upward, and the

magnitude may be higher than that of the equity process.

While the empirical test focused only on the stochastic volatility pro-

cess, I have simulated various models that incorporated jumps. From these

results it was determined that jump risk factors are not the only priced fac-

tor when it comes to option values. Jump models without priced stochastic

volatility factors cannot explain the full degree of bias present in Black-Scholes

implied volatility.

The empirical tests performed by Christensen and Prabhala (1998) fo-

cused on index options, and while I replicate their results for the S&P 100 and

S&P 500, the main focus is on the bias in gas contracts. The complication of

examining gas contracts lies in the significant TSOV and seasonality tests. I

am able to demonstrate the upward bias nature in BIV, and link this bias to

the market price of volatility risk.

The resulting empirical tests for λσ revealed that the factor is negative

and significant for both the equity and gas process. I have introduced a tech-

nique to link the latent volatility factor to the implied volatility from a 30 day

option contract which allowed for simple estimation of λσ. The major con-

clusion is that the market price of volatility risk is an important price factor,

and lends explanation to why option traders tend to be short. This effect is

especially noticeable in the gas contracts, where the high load months in the

72

winter experience higher risk premiums.

The work in this area is still incomplete. It is necessary to test these

results further, especially for the gas contracts. Can these results hold up to the

non-parametric tests of Bakshi and Kapadia (2001) and Coval and Shumway

(2000)? Additionally, what happens when ITM and OTM options are included

in the data, and when jumps are included in the price process. I address these

issues in the following chapter with a test for model fit for various parametric

option model candidates as well as infer the multiple market prices of risk.

73

Chapter 4

Empirical Performance of Option Models for

Natural Gas and Estimation of the Market

Price(s) of Risk

4.1 Introduction

The intent of this chapter is to examine in greater detail the dynamics of

the natural gas markets. This first entails estimation of the implicit parameters

underlying a variety of option models to capture cross-sectional performance.

This estimation will not only reveal how mis-specified the Black (1976) option

model is, but also tells by comparison how well certain models do fit the data.

This leads directly into further estimation on the market price of volatility

risk by incorporating the risk-neutral estimates from the model performance

analysis. With the inclusion of jumps to the model, errors caused by model

misspecification are minimized and the full cross-section of option price data

can be utilized to infer the priced risk factors.

The current state of option pricing offers a wide range of models that

relax the assumptions of the Black-Scholes model. The models of Hull and

White (1987), Heston(1993), Melino and Turnbull(1991, 1995), and Stein and

Stein (1991) have expanded upon Black-Scholes by dropping constant volatility

in favor of stochastic volatility. The stochastic volatility model was better able

74

to capture the skewness in option prices, resulting in improvement of Black-

Scholes in terms of model fit, through the correlation between the price and

volatility processes and variation in volatility. Bates (1996) and Scott (1997)

added return-jumps to the framework, allowing the model to capture skewness

without adversely affecting kurtosis. The inclusion of return jumps had the

additional impact in less over-parameterization error due to less reliance on

volatility variation to capture short-term volatility skews. This is shown in

the works of Bakshi, Cao and Chen (1997) and Pan (2000). The most current

extensions to the model have been the inclusion of volatility-jumps by Duffie,

Pan, and Singleton (2000), and crash risk by Bates (2003). The benefits to

volatility-jumps are shown in Bakshi and Cao (2003), who test the sample

on individual equity options. Most empirical tests completed have examined

option model performance in terms of equity and index options. While our

knowledge is quite extensive for this market, the results for equities are not

directly transferable to other markets, such as foreign exchange contracts and

commodities futures. The first goal of this chapter is to examine the perfor-

mance of these option models to assess overall fit and capture the risk-neutral

dynamics of natural gas option contracts.

By comparison very little is known about the commodities market in

term of option pricing and empirical performance of various option models.

Empirically, there is observed positive skewness in Black implied volatilities,

higher levels of volatility, and a potential negative market price of risk. These

factors contribute to a distinct market and require a better understanding of

75

how to model commodities option pricing. To explore empirical and mod-

eling aspects of commodity options, I will test a variety of models, start-

ing with Black-Scholes/Black and working up to the Duffie, Pan, and Sin-

gleton (2000) model accommodating stochastic volatility, return-jumps, and

volatility-jumps. The advantage of testing this type of model is that it in-

corporates the stochastic volatility model of Heston (1993) and the stochastic

volatility with return-jumps model of Bates (1996). In addition, I test the

stochastic volatility with jumps model (SVJ) with the additional adjustment

for the term-structure of volatility. As the option approaches maturity, there is

an observed significant “ramping up” of implied volatility. In the commodities

market where there is such a significant TSOV, the addition of term structure

parameter implicit within the model seems like a natural extension.

Each model in evaluated on in-sample performance, cross-sectional per-

centage pricing errors, and 2 out-of-sample metrics. The percentage pricing

errors are generated using the structural parameter estimates including the

implied volatility, and the given futures price, strike price, risk-free rate, and

time to maturity for that day. The out-of-sample tests use the 1-day and 5-day

behind implied parameters to price the current day option value. These tests

provide direct evidence for model misspecification and will penalize a more

complex model for overfitting.

Based on the sample of 98,006 usable closing option prices from Jan

1999 to October 2002, I find that incorporating a TSOV effect demonstrates

little improvement over the Bates (1996) model, while adding independent

76

volatility jumps to the Bates model has the best overall performance. Similar

to the results for equities, the stochastic volatility model of Heston (1993) im-

proves in-sample performance by close to 50% as compared to the Black model

for the full sample. The inclusion of return-jumps, and subsequently volatility-

jumps, further improves upon the Heston model, but in smaller increments.

Controlling for seasonality and year effects dramatically changes the structural

parameter estimates, as volatility variation, process correlation, and jump size

appear to be yearly and monthly dependent. The winter months especially

show large positive correlation and mean jump size. The 2000 expiration con-

tracts show tremendous volatility variation and high positive correlation in

part due to the energy shortage and deregulation. These effect are model

independent. However, volatility variation dramatically declines when return

jumps are included. This is quite telling as the Bates model tends to improves

model fit for OTM short-term calls as well as reducing the pricing bias for

OTM long-term calls. Surprisingly, the correlated double jump model is out

performed by the independent double jump model across all years and sea-

sons. The parameter values indicate that the double-jump model shows close

to a zero correlation between return and volatility-jumps. While the indepen-

dent double jump model is a nested model, the arrival rates for the return

and volatility-jumps are independent, possibly explaining the improved in and

out-of-sample model performance.

The second objective is to confirm a negative market price of volatility

risk for commodities. The findings of the previous chapter suggest a negative

77

market price of volatility risk for both equities and commodities. The results

for equities are confirmed by the non-parametric tests of Bakshi and Kapadai

(2000) and Coval and Shumway (2001). Chapter 3 implemented a technique

to test a weighted average estimate of implied volatility by using a mean re-

verting stochastic volatility framework which calibrates the risk-neutral world

to the risk-neutral parameter estimates through the market prices of risk. The

findings for natural gas contracts show a significant and negative market price

of volatility risk for the entire sample and each monthly contract. However, the

relative model misspecification by ignoring return-jumps forces the volatility

variation to capture most of the upper moments. This results in an upward-

bias estimate of the market price of volatility risk since the implied volatility

estimate ignores the full cross-section of option prices. In this study, I use the

structural parameter estimates from the model performance estimation and

Monte Carlo simulation to combine the risk-neutral and real-world distribu-

tions to solve for the market prices of risk. This is accomplished by jointly

minimizing an objective function that takes the difference between the actual

volatility and model estimated volatility as well as the Black implied volatil-

ities and model estimated implied volatility. The resulting estimation of the

risk factors is improved by incorporating the cross-section as well as the time

series of spot and option prices. Allowing for return-jumps places less restric-

tion on the stochastic volatility parameters, resulting in improved estimation

and minimizes the error resulting from model misspecification.

Of equal importance is to resolve the mystery of the direction of the risk

78

premia for natural gas contracts. To this point there has been no conclusive

finding that can pinpoint the sign and magnitude either through a lack of data

or degree of volatility inherent in the contracts. Through this technique I hope

to shed further light on this estimation.

I plan to address the following questions.

• Which model best fits the positive skewness and high kurtosis present in

the risk-neutral distributions of commodities prices

• How much does TSOV matter in model fit

• How are the parameter estimates distinct from those typically found for

equity index options

• What are the market price(s) of risk, especially the market price of

volatility risk

The chapter is organized as follows. Section 2 presents the double-jump

option-pricing model and all other models to be investigated with the added

TSOV adjustment. Section 3 describes empirical issues and the construction

of the option sample. Section 4 describes the estimation procedure,in-sample

option model fit results, and out-of-sample results. Section 5 and 6 focus

on the estimation technique and the market prices of risk. Conclusions are

provided in Section 7.

79

4.2 Modeling Issues

I present a closed-form option-pricing model similar to that of Pan

(2000) and Bates (1996), but in addition add in time dependence to the level

to which volatility reverts to. The addition of the time dependence of volatil-

ity model with all those considered in Bakshi, Cao, and Chen (1997), Bates

(2000), and Pan (2000), forms the basis for empirical comparisons. Bakshi,

Kapadia, and Madan (2003) provide theoretical foundations for the existence

of less negatively-skewed and fat-tailed individual risk-neutral distributions for

firm equity options. They argue that kurtosis is a fundamental determinant

of option prices when the risk-neutral distributions are less skewed. This al-

lowed Bakshi and Cao (2003) to implement the double-jump option-pricing

model where return-jumps and volatility-jumps are the primary source of ex-

cess kurtosis. However, the knowledge is less complete for commodity options

and requires the testing of the prior models along with the alternative model

incorporating the TSOV. I can make no such claim about the source of excess

kurtosis, especially since there is a fair degree of skewness. This skewness,

which is mostly positive, has had occurrences of severe negative skewness for

periods during the 2000 and 2001 expiration contracts.

4.2.1 Data Generating Process for the Double Jump Model

I will ensue with a quick review of the double-jump option model under

stochastic volatility as in Duffie, Pan, and Singleton (2000) for completeness.

The underlying non-dividend-paying futures price, Ft, is governed by the follow

80

risk-neutral dynamics

dFt =√VtFtdz

Ft + (ext − 1)Ftdq

Ft − EQ(ext − 1)dqF

t Ft (4.1)

dVt = κ(θ − Vt)dt+ ξ√Vtdz

σt + ytdq

σt (4.2)

where dzFt and dzσ

t each represent standard Brownian motion with cor-

relation ρ. The Poisson jump-counters, dqFt and dqσ

t , determine the probability

of a return or volatility jump respectively. With the understanding that the

future process applies to any given contract i, the subscript on Ft, Vt, and all

structural parameters for succinctness are suppressed. The futures price pro-

cess outlined in equations (4.1)-(4.2) can be explained in the following manner.

At the outset, observe that there is no futures price drift.This precludes any

notion to model a stochastic process for the interest rate since the drift does

not equal the risk free rate1. EQ(ext − 1)dqFt is the correction necessary to

generate a zero drift rate.

The price is governed by two specific elements, the continuous path√VtFtdz

Ft and the jump component (ext − 1)Ftdq

Ft . For this model, return

jumps xt, are not the only source of discontinuity. The stock price is ad-

ditionally altered by volatility jumps, yt. The return jumps are percentage

price jumps, with Poisson arrival, while volatility jumps are level jumps in

Vt. Duffie, Pan, and Singleton (2000) note that there is no need to specify

1The economic impact of including a stochastic interest rate process does little to improvemodel fit. For direct evidence observe Bakshi, Cao, and Chen(1997)

81

the volatility jump as two-sided, thus yt is modeled as the exponential of the

mean-size of the volatility jump distribution. This preserves the integrity of a

non-negative volatility.

The inclusion of volatility jumps to the well known stochastic volatil-

ity model with return jumps suggested by Bates (1996) allows for additional

model flexibility to capture higher moments. From the option model pricing

standpoint, it allows for the flexibility in generating either independent return

and volatility jumps, the existence of only one jump, or correlated jumps. For

this particular case, assume that λx,y is the arrival rate of a correlated double

jump. This jump intensity can be a function of Vt, and probability of jump

occurring is Prob[dqFt = 1] = λx,ydt.

To generate correlated and simultaneous jumps, Duffie, Pan and Sin-

gleton (2000) assume this conditional distribution.

xt|yt N(do+ δx,yyt, σ2x,y) (4.3)

where do+ δx,yyt and σ2x,y are the mean and variance respectively. This

specification allows for positive volatility-jumps and negative return-jumps if

δx,y is negative. The parameter do is unrelated to volatility, and is interpreted

as the component of return jumps that is independent from volatility.

82

4.2.2 Double Jump Option Model

The characteristic function for the double-jump model is presented be-

low:

J(t, τ ;φ) = exp[A(τ, φ) +B(τ, φ)] (4.4)

where A(τ ;φ) and B(τ ;φ) are shown in the appendix. It is necessary

that the characteristic function satisfy the Partial Integro-differential equa-

tion:2

0 =1

2JSSS

2V + JS

(r − λx,yEQ

t (ex − 1))S +

1

2JV V σ

2νV

+ JV (θν − κνV ) + JSV σνρSV − Jτ − rJ

+ λx,y

∫ ∞

0

∫ ∞

−∞[J(Ste

x, Vt + y)− J(St, Vt)]Φ[x, y]dxdy

The characteristic function of the state-price density is the main tool

that allows for the calculation of the risk-neutral parameter estimates. Given

the data generating process in (4.1) and (4.2), the value of call option on a

futures contract, Ct(τ,K), where τ is time to maturity and K is strike price,

has a price equal to

Ct(τ,K) = e−rτ (FtΠ1(t, τ)−KΠ2(t, τ)) , (4.5)

where the risk-neutral probability functions are given by:

2Since the goal here is not a complete review of the model, refer directly to the Duffie,Pan, and Singleton (2000) model for a complete discuss on the partial differential equationshown in 4.5

83

Π1(t, τ) =1

2+

1

π

∫ ∞

0

Re

[e−iφ log[K]ψ(t, τ ;φ− 1)

]dφ (4.6)

Π2(t, τ) =1

2+

1

π

∫ ∞

0

Re

[e−iφ log[K]ψ(t, τ ;φ)

]dφ (4.7)

where ψ(t, τ ;φ−1) is found by evaluating the characteristic functions at

the point φ− 1 and φ. These functions are shown in the appendix. Unlike the

treatment for equity options, there is the additional concern of American style

exercise for these gas options. The characteristic function are adjusted similar

to the style of Bates (1996) incorporating the early exercise premium. The

valuation of the put options is then derived from American futures put-call

parity by taking the mean of the upper and lower bounds3.

Starting with Heston(1993), incorporating stochastic volatility within

the option model has greatly improved the pricing performance over the Black

option model. Incorporating correlation between the volatility and price pro-

cess allows the stochastic volatility model (henceforth known as SV) to gen-

erate skewness that is empirically observed across the cross-section of option

prices. Bates (1996) further added to the model with the inclusion of return-

jumps with stochastic volatility (SVJ) and as shown by Pan (2000), resulted

in best capturing the short and long term dynamics of the cross-section index

option prices. The inclusion of volatility jumps, especially correlated double

jumps (DPS), can reduce the burden on return jumps by capturing higher

3The upper bound for the put option is Ct + K − Fte−rτ . The lower bound is Ct +

Ke−rτ − Ft.

84

third or fourth moments when necessary. For example, to achieve more posi-

tive skewness without restricting excess kurtosis, an upward jump in volatility

is accompanied by an upward return jump when δx,y > 0. This is especially

important for gas options for two reasons. First, besides empirical observa-

tions, there is little understanding in terms of structural parameter estimation

and option model performance. Hereto, it is necessary to test each model to

gain further insight into this market. Second, the market is highly volatile

as compared to equities with large volatility skews/smiles at various maturi-

ties. This requires added option model flexibility even beyond equity option

estimation.

4.2.3 Independent Double Jumps and TSOV considerations

As mentioned earlier, the SV and SVJ models are contained within the

double jump model. They are directly attained from the the double jump

model when the volatility and return jumps are independent. This results in

separate jump arrivals such that λx is the arrival rate for return-jumps and

λy is the arrival rate for volatility-jumps4. The characteristic functions for the

independent double jump model are shown in the appendix. To generate the

Heston (1993) model, setting λx = 0 and λy = 0 within (SVDJ) will result

in no return or volatility jumps. For SVJ, restricting to λy = 0 generates

only return jumps. Within this chapter, I have not examined the case of

volatility only jumps, (SVJV), given the results shown in Bakshi and Cao

4Bakshi and Cao (2003) suggest the return jump distribution as x N(log(1+µx)− 12σ2

x, σ2x)

85

(2003) demonstrating the performance improvement of SVJ over SVJV.

In addition to these models, I incorporate a TSOV adjustment similar

to that of the earlier section. The intent here is to capture the significant

ramping up of volatility in Black implied volatility (BIV) for close to expira-

tion contracts. This implies that the level to which volatility reverts, θ, has

time dependence. Section 2.2.2.2 suggest that a reciprocal specification can

best capture the TSOV effect in gas markets5. Given time dependent θt, an

adjustment is made in the characteristic function such that

θt = θf(τ) (4.8)

where f(τ) = α+ βτ. The parameters α and β are the TSOV parameters

that capture the increase in volatility and long run mean respectively. The

long run mean is normalized by τ , the time to expiration. The resulting model

will be abbreviated as the SVJT model.

4.3 Data

The futures price and option price data was collected from Bloomberg

and prices were confirmed by external closing price from the Citadel Group.

5The additional specifications were the Schwartz (1997) exponential form and a quadraticform. The exponential specification did outperform the reciprocal in certain cases wherethere was a large disparity between monthly contracts over certain years. However, in allcases, the reciprocal form was best able to capture significant TSOV effect without sacrificinglong-term fit.

86

The futures and option prices are daily closing prices for the January 2000

contract through the August 2003 contract. The final collected option price

is for the August 2003 contract with 305 days until expiration. The typical

contract has usable observation from 360 days until maturity for strike prices

from $2 to $8 over 5 cent increments. For estimation purposes, I examine

all calls and puts on each monthly contract from January 1st, 1999 through

October 26, 2002. Unlike equity index options, I have to be concerned with

liquidity issues since there are low volume and wide bid-ask spreads for many

strike prices. In estimation, strike prices with bid-ask spreads greater than

$0.25 will not be included. Additionally, commodity options are American

style exercised and most current options models can only handle a European

payoff. This can be controlled for in two ways. The first is to implement

the methodology adopted by Bakshi and Cao (2003), whereto restricting the

sample to short-term maturity out-of-the money options minimizes the chance

of early exercise. The second technique is to adopt the Barone-Adesi and

Whaley (1987) technique implemented by Bates (1996). As shown in the

appendix, I choose to adopt this technique to increase the sample of options

tested. By adopting the first method, the sample would be reduced down

from 98,006 usable observations to 23,074, substantially reducing the power of

future tests.

This data allows for the possibility of testing over many years as well

as within years. From the prior section it has been shown that there is a

significant term structure of volatility for gas contracts, and it may be more

87

appropriate to test these contracts on a yearly basis versus grouping each

year together. It is also noted that each month has a specific TSOV, which

additionally requires testing each month separately. Consequently, results will

show model fit and structural parameter estimations for both seasonal and

yearly results.

The prices collected are closing prices which are taken to be the mid-

point of the bid-ask spread. I exclude prices which are less than 3/8 of a

dollar, and prices that occur within 7 days of term. These restrictions are

greater than those reported by Bakshi and Cao (2003) since there are stronger

liquidity concerns with commodity options. Finally, all quotes not satisfying

the arbitrage condition are omitted.

Of the 98,006 observations, 46%(54%) of the observation were calls(puts).

For option maturity, there are 25%, 56%, and 19% observations when the

sample is divided into expirations of >180 days, 60-180 days, and <60 days

respectively. By moneyness, the sample is partitioned into 5 groups, deep out-

of-money (DOTM), out-of-money (OTM), at-the-money (ATM), in-the-money

(ITM), and deep in-the-money (DITM). The observations for each group are

5%, 18%, 25%, 27%, and 25%, where the bounds for DOTM, OTM, ATM,

ITM, and DITM calls(puts) are a strike/spot ratio > 1.2 (<.8), 1.05-1.2 (.8-

.95), .95-1.05, .8-.95 (1.05-1.2), and <.8 (>1.2) respectively.

88

4.3.1 Understanding the volatility in gas markets

A closer look at table 2 reveals volatility levels of daily futures price

changes of approximately 25% for any given month over 10 years. These

statistics are misleading since they do not reflect the variability of any given

contract for a given year or the degree of variability of different time periods

within a given contract. For example, using the data in 2.2.2.1, a closer look

at the February gas futures contract reveals yearly variations as high as 39% in

1997 and as low as 22% in 1992. Within time periods the average daily return

variation for 0-60 days till expiration is 55%, for 60-180 days it was 24%,

and for 180-360 days it was 15%. The February 2001 contract experienced

around 90% volatility for the short-term period of the contract as compared

to 13% volatility for the period from 180-360 days. The variation in sub-

period volatilities shows an increase from the early contracts (1991-1996) to

more recent contract years (1997-2003), and this increase is observable for each

month.

The potential measurement error issues that arise when dealing with es-

timation using option contracts require a closer look at the volume of contracts

traded and the bid/ask spread associated with each contract. If price of the

option contract is measured with error, the resulting inverted implied volatility

will be incorrectly estimated, and so to0 the risk-neutral parameter. The liq-

uidity issue is important because if there is minimal volume traded for a given

contract it could potentially result in sticky and non-informative prices. The

November futures contract tends on average to trade 254,000 weekly contracts

89

at the Bid price and 179,000 at the Ask price 6. By comparison the January

contracts trades a volume of 317,030 at the Ask price and 201,280 at the Bid

price. In terms of dollar weekly volume it equates to approximately $2,000mm

each week for any given monthly futures contract. It terms of bid/ask spreads,

the typical spread is on average around $.10 with a high of around $.30 for

any given month. For the options, the typical volume is much lower than the

futures contracts, and tends to increase as the option approaches maturity.

The bid/ask spreads in the option markets are similar to those for the futures

markets, with a high of around $.20. 7

4.4 Model Estimation

Prior to estimation of the underlying parameters, I felt it necessary

to gauge the severity of the smile/smirk pattern of implied volatility from the

Black Model. This was accomplished by solving for the Black implied volatility

(BIV) with an early exercise correction for each option price at a given strike

price and time to maturity. The BIV were then categorized across five levels of

moneyness and three maturity distinctions. An equally weighted average was

taken of the volatilities within each basket to form an average implied volatility.

The results of the averaging can be seen in tables (21)-(22). Additionally,

6Through the period Jan 1st 2000 to Oct 13th 2003. This is a constructed average of allthe November futures contracts where typically the volume for each yearly contract increasescloser to maturity.

7These option contracts rarely are over $1.50 per contract, and a $.05 bid/ask spreadimplies a $500 dollar difference. Any bid/ask spread greater than $0.15 was thrown out ofthe sample.

90

the sample was broken up into eight sub-samples, 4 seasonality groups and

4 yearly expiration groups. What is most evident is the degree of volatility

present within the natural gas market. Typical volatilities associated with

equities are on the order 20% to 30%, whereas this sample shows volatilities

closer to 50% to 60%, with short-term maturity volatilities exceeding 100%

in most cases. The cross-sectional pattern also exhibits a smile pattern as

the call (put) option goes from deep ITM (OTM) to deep OTM (ITM). The

longer maturity contracts tend to exhibit a positive smirk for both the call

and put options while the short term options do not appear to conform to

any particular pattern. This requires further examination within the sub-

period given the strong seasonality and yearly effects within this market. As

shown by the winter sub-sample, short-term contracts tend to demonstrate

the largest smile/positive smirk pattern, although the smirk appears reversed

for the fall and summer sample. A closer look at the year effect shows that

this same negative smirk appears in the 2000 expiration contracts, and later

reverts back to a positive skew in the following years. This effect can be

attributed to the energy shock that occurred in California, and the resulting

effect that this had on natural gas prices. This suggests that the candidate

option models be able to demonstrate the ability to capture both positively

and negatively skewed distribution across years and seasons. As a result of

the switching from negative to positive skewness the aggregate effect appears

to be a relatively flat cross-sectional pattern as shown in the short-term BIV

for the full sample. Therefore, the implicit correlation between the price and

91

volatility process may be less on aggregate than within years and seasons.

Given the American styled payoff, the disparity between call and put

BIV is greater than that typically observed in equity index option. However,

the cross-section patterns remain the same. For the winter sub-sample, both

calls and puts demonstrate a positive skew for different maturities, while the

summer and fall contracts show a negative skew. The shorter the term of the

contract, the greater the variation between puts and calls, partly due to the

increase in volatility, decreased sample size, and increased variation amongst

the sample.8

4.4.1 Estimation Technique

Adopting the methodology implemented by Bakshi, Cao, and Chen

(1997), Dumas, Fleming, and Whaley (1998), Jackwerth and Rubinstein (1997,

1998),and Whaley (1982), I infer the structural parameters and model im-

plied volatility for the six candidate models: (I) the Black model (B), (II)

the stochastic volatility model (SV),(III) the stochastic volatility with return-

jumps (SVJ), (IV) the stochastic volatility with return-jumps and TSOV cor-

rection(SVJT), (V) the stochastic volatility with independent volatility-jumps

and return-jumps (SVDJ), and (VI) the stochastic volatility with correlated

volatility-jumps and return-jumps (DPS). For the given model, it requires

the estimation of volatility Vt and the implied parameter vector ζ. Consider

the stochastic volatility model case, where the implied parameter vector is

8For the 2002 year, the deep OTM short-term call option had only 2 observation of note.

92

ζ ≡ {κ, θ, ξ, ρ}.

For a given point in time, there exists a future price Ft, and M option

prices over a range of various strike prices. For M = 1, ....m, let Θ(τ,Km) be

the actual price of the option and Θ̃(τ,Km) the model estimated price from

equations (4.5)-(4.7) at time to maturity τ and strike price Km. I minimize

the objective function below over the implied volatility and parameter vector

to solve:

Γt ≡ minVt,ζ

M∑m=1

(Θ(τ,Kn)− Θ̃(τ,Kn))2 (4.9)

The objective function estimates daily implied spot variances and struc-

tural parameters. It is important that there are m > j observations each day,

where j represents the number of parameters to be estimated. For this par-

ticular sample, this resulted in 2345 daily estimated structural parameters.

The benefits of implementing an estimation using the cross-section of option

prices versus the historical time-series greatly reduces data requirements and

significantly improves performance.9 This has been noted by several authors,

most recently by Bakshi and Cao (2003) and Chernov and Ghysels (2000).

This implied parameter techniques is consistent with the current practice of

judging the relative performance of the candidate model to that of the Black

model.

9Many authors have adopted techniques using time series data on stock and option pricessuch as Bates (2000), Pan (2002), and Eraker (2001). Those particular methods may notbe implementable for this data set. Since the data is over a three year span, there may notbe enough observation to derive significance from the time-series tests.

93

By taking the minimum difference between the actual option price and

the estimated model price results in assigning more weight to near-the-money

and longer dated options. Given that the highest volume occurred for options

close to the money with the smallest bid-ask spreads, it was best to implement

this minimization versus the minimization of the sum of squared percentage

errors. The alternative would have placed more weight on deep out-of-money

and short-term options, where the total volume traded was less and option

price more susceptible to error.10 This approach is consistent with the studies

of Bates (1991, 1996a,c) Madan and Chang (1996), and Baskshi, Cao and

Chen (1997).

4.4.2 Structural Parameter Estimation and Model Performance

Using the 98,006 observations across all calls and puts, I report in

tables 26-51 each model’s implied spot volatility, daily averaged structural

parameters, and total sum of squared pricing errors (RMSE). What is directly

observable is the distinct difference in the parameter estimates for natural

gas contracts as compared to equity index estimation.11 The underlying spot

volatility is on the order of 30% higher than that found in equity markets,

and the variability of the volatility is almost an order of magnitude higher.

10Refer to Hentschel (2002) for a discussion on the possible sources of measurement errorin regards to options and option prices. The thought here is that deep out-of-the-moneyoptions may be thinly traded, and thus result in stick prices and incorrect inverted volatilityestimates.

11For direct evidence on equity index structural parameter estimation refer to Bakshi,Cao, and Chen (1997), Bates (1996), and Pan(2000)

94

Correlation between the processes is positive, as is the mean jump size; not

surprising and highly suggestive of a positive volatility skew.12 The frequency

of jumps is almost double than that of equity markets as is the variability in

the jumps.

Using Black as the base case, there is clear performance improvements

by going to a stochastic volatility framework. The performance improvement

by adding stochastic volatility to the model decreases the RMSE by 50%.

Adding jumps to the price process increases model performance an additional

17%. A closer look at the parameter estimates shows the difficulty the SV

model has in fitting the data. The volatility of variance process, ξ, is higher

in the SV model, which is consistent with the results for equity index data.

What is unusual is how high the parameter is by comparison. The volatility

series associated with gas markets can experience volatilities well above 100%,

which occur only in very rare circumstances for equities.13 In the later months

of 2000, volatilities close to maturity for the monthly contracts rose to over

300%. These results are potentially linked to the time period over which the

data was collected. Gas prices in the 90’s were less volatile due to regulated

markets whereas today’s prices are unregulated. In addition, due to some of the

trading practices of companies such as Enron and El Paso, short term liquidity

demands were created in certain regions and in combination with excessive

temperatures, resulted in tremendous volatility for energy and massive price

12Pan finds a correlation coefficient of around -.53 and mean jump size of -19%.13take for example the implied volatility for the VIX index in 1987, which was 150%.

95

spikes.14

The inclusion of the TSOV parameters does little to improve model fit.

However, when examining options with expiration of 60 days or less, SVJT

does have small improvements over the SVJ model. Concurrently, the TSOV

parameter helps specifically with months that experience large increases in

volatility close to maturity such as the winter months when demand for energy

is highest. In terms of overall performance, the addition of a TSOV within

the characteristic functions does little to help as compared to adding jumps

in volatility. The results are similar to adding a stochastic interest rate to the

model.

Given the high degree of volatility in these markets, it is not surprising

to observe high volatility variation. This variation is driven by the observa-

tions15 where volatility is over 150%. Note in tables 27-32, ξ in the SVDJ

model goes from .65 to 2.655 when including all observations. The SV model

is confined to use ξ and ρ to fit the level of skewness and kurtosis of the data,

resulting in tremendous volatility variation as compared to the other candidate

models. Additionally, the implied spot volatility is close to 50% greater than

the models that incorporate jumps. This high volatility is necessary to specif-

ically capture the high kurtosis present at the tails of the distribution. The

inclusion of jumps both diminish ξ and implied volatility, since price jumps

14The results are skewed because of the excessive shortage California experienced in thesummer month of 1999 and 2000, resulting in massive energy spikes.

15about 200

96

can capture more skewness and kurtosis without having an adverse effect on

the other implicit parameters. As will be shown, this avoids the under-pricing

of long term options ITM and overpricing OTM options.

Adding volatility jumps with return jumps improves overall fit by 4.9%

and 2.1% for the SVDJ and DPS model respectively. By comparison, Bak-

shi and Cao (2003) find an overall performance improvement of 3% for the

DPS model over SVJ for individual stocks. Surprisingly, they find that the

SVDJ model performs worse than SVJ. Examining δx,y reveals close to zero

correlation between return and volatility jumps for natural gas, whereas the

correlation is significant and negative for large individual stocks. Observe do is

also close to 70%, further documenting the independence of return-jumps from

volatility-jumps. This suggests that SVDJ may be more appropriate. A closer

look at volatility-jumps shows an arrival rate similar to that of return-jumps,

with a mean jump size of 2.1%. The positive volatility and return-jump, along

with positive correlation, demonstrate the co-movement of price and volatility

in the gas markets.

As noted earlier, the correlation between price and volatility processes

tends to be negative in the equity markets. The level and direction of correla-

tion for commodities is the opposite, as prices tend to move in similar direction

as that of volatility. The findings over all contracts suggest a correlation of

.15 depending on the model (when the 2000 year is excluded the correlation

rises to 33%). The intuition for this is a direct result of the nature of this

type of asset. As a whole the general public is net users of energy versus net

97

savers of equities. As consumers, we tend to consume energy versus store it

for a later date. In the equities markets, as volatility increases, the required

rate of return increases, and the price of the stock falls. Translated into a

CAPM world, equities are a positive beta assets, with a positive market price

of risk and expected return in excess of the risk free rate. For commodities,

when volatility increases the premium for consumption increases, and prices

increase. An argument for this finding is suggested by Day and Lewis (1993)

who estimate a negative market price of risk for oil. With a negative market

price of risk and in combination with the notion that the public are net con-

sumers of energy, it becomes apparent that the correlation between the price

and volatility process should be positive. As a result, the energy markets tend

to experience price spikes versus crashes. The findings for the jump parameters

show an arrival rate between 1.35 and 1.11 with a average jump size between

24% and 13%. By comparison, the findings of Bakshi, Cao, and Chen (1997)

for the S&P index have jump sizes on the order of -5% with a -9% for short

term options.

The analysis of in-sample fit would be incomplete without examining

the effect across different years, seasons, and time to maturity. Specifically,

it is necessary to control for seasonality patterns, where typical demand for

heating in the winter months results in greater volatility in the gas futures

markets. The results for in-sample parameter estimation and model fit can be

found in tables (27)-(51).

The maturity of the contract clearly impacts the parameter estimates,

98

as mean jump size, deviation, and frequency are significantly higher for short-

term options versus long-term. The long run mean does not change signifi-

cantly, but the variation in volatility dramatically rises. The correlation falls

close to zero for short-term options, nor surprising given the volatility smile

shown in figures (13)-(14). The implied spot volatility increases almost 38%,

demonstrating the large TSOV effect in gas options

What is most evident from the parameter estimation is how volatile the

2000 and 2001 expiration contracts appeared. As shown in figures (9)-(14), the

price variability in the futures contract has fluctuated greatly over these years

versus the mid to late 90’s. This may be a direct result of the energy shortage

that occurred and the markets adjustment to deregulation. The variation in

volatility, ξ, is 20 times higher in 2000 than in 2002-2003, and on the order of

5 times higher in 2001. The correlation is highly negative with negative return

jumps (except for the DPS model) in 2000, suggesting a negative volatility

skew. This appears to be a year effect, as the following years have mostly

positive correlation. This negative skew in 1999 intuitively makes sense; as the

price increased dramatically, OTM puts became expensive to protect against a

correction for this shortage. Since the price had spiked, jump fears subsided in

favor of crash fears. The volume of ITM puts declined, and the bid-ask spread

widen, further escalating the apparent skew. The following years this negative

skew became more of a volatility smile/positive smirk once the energy shortage

had been resolved. The DPS model, while having a positive correlation for the

2000 expiration contracts, compensates by having large negative mean return-

99

jumps. By using the correlated double jump structure, the DPS model places

less restriction on ρ to capture the higher moments, and in this case possibly

reveal a more appropriate relationship between price and volatility. In the

years that follow, the correlation between volatility and return jumps is close

to zero and the parameter estimates are similar to that of SVDJ.

The prevailing notion that winter months tend to experience greater

volatility due to the demand for heating seems plausible given the 10% to

20% higher implied volatility in long-term options versus other seasons. The

average jump size is also an additional 7% to 8% higher than other seasons for

similar jump frequency. When examining short-term options, winter months

do experience an increase in volatility, jump size, and jump frequency, as

compared to the long-term counterparts, but by comparison, do not nearly

demonstrate the magnitude increase as shown by the fall months. Implied

volatility was as high 158.94% from the SVDJ model, with three jumps arriving

per year. Further examination of ξ for summer and fall short-term options

reveal close to an order of magnitude increase as compared to the long-term

options and winter and summer seasons. The reliance on such variation in

volatility in these particular months appears to be inconsistent since most

results suggest that the greatest variability should occur in December through

February. The results emerge from the 1999-2000 supply shortage effects that

caused energy prices to spike, not because of some reverse seasonality effect.

100

4.4.3 Out of sample pricing performance

The results in the prior section have shown the improvements in in-

sample model fit when including return and volatility jumps over stochastic

volatility and Black model. In sample model performance does not imply one

model’s dominance over another given the potential for over-fitting or over-

parameterization. Over-fitting may result in poor out-of-sample performance,

especially in more complex, parameter dependent models that cannot capture

the underlying return dynamics. Along the lines of Bakshi, Cao, and Chen(

1997), Dumas, Fleming and Whaley (1998) and Pan(2000), I perform three

tests as safeguards against potential poor out-of-sample performance. The

first two tests use the underlying parameters to price options 1 day behind

and 5 days behind. The third tests for pricing errors for different strikes and

maturities.

In these out of sample tests, the previous day’s implicit parameters

were used to calculate today’s model price. This price is then subtracted from

the actual price and the absolute value is taken to compute the absolute pric-

ing errors. All options are used ranging from all maturities and strike prices.

As compared to what is known about equity index out-of-sample errors, there

has been little documentation on commodity options. Given the results of

the in-sample analysis, it should not be surprising to observe larger pricing

errors. The results in table 23 show the average absolute dollar pricing errors

by moneyness and maturity. The most severe mis-pricing for the Black model

occurs for short term deep out-of-money options with puts exhibiting similar

101

behavior. The average dollar pricing error was $0.24, which is a significant

portion of the option price. As the option moves towards at-the-money, the

mis-pricing declines, with an average dollar pricing error of $0.04. This is the

general pattern for long-term and medium-term options, and is highly sugges-

tive of a model that is able to capture the cross-sectional dispersion in option

values. Using the Black model as a reference, the five additional models can

now be tested to show the improvements over this initial benchmark. In terms

of performance the SVDJ model shows the lowest pricing error of $0.031 for

short-term deep out-of-money calls, as compared to the $0.24 of the Black

Model. By comparison there is significant, but smaller performance improve-

ment when examining the deep out-of-money puts. This may be a function

of sample size, as there were only 17 options within this subset. Looking

at short-term ITM calls and ITM puts shows similar performance improve-

ments on order of $0.13 to $0.06. Surprisingly, the DPS model had larger

pricing errors for the deep out-of-money call options, and similar numbers to

SVDJ for the put options. The hierarchy in terms of improvement shows that

the inclusion of stochastic volatility improves upon the Black model, and the

inclusion of return-jumps further improves upon the SV model. With the in-

clusion of return jumps performance improvements are quite similar for the

SVJ, SVJT, SVDJ, and DPS models across most maturities and moneyness.

With all models, the dollar pricing errors are highest for short-term options,

deep out-of-money. The inclusion of the volatility jumps has, in some cases,

shown the ability to reduce these errors, given the model’s ability to generate

102

addition peaked implied volatility-distributions. The 5 day-ahead results do

little to change the conclusions generated from the 1 day-ahead section.

The percentage pricing errors are indicative of the moneyness/maturity

performance of each model. The errors are calculated from the sample average

of the daily difference between the model price and the actual price, divided

by the actual price. The results reveal the degree of over or under-pricing for

each model. The B model tends to under price ITM calls and over-price OTM

calls. With the inclusion of stochastic volatility, the mis-pricing is reduced, but

OTM short-term options are still overpriced by 19.07%. Adding jumps to the

model reduces the errors further, including reduced mis-pricing for longer-term

options.

4.5 Mean-Reversion in Stochastic Volatility

Estimation of the various price risk factors requires either extensive

historical data or, as shown by Pan (2000), the ability to use the both spot

prices and the cross-section of option prices. It is my intent to implement

a similar technique, using the knowledge of ex-post volatility data and the

estimated structural parameters found in the prior section. Using Monte Carlo

simulation and the closed form solutions for option prices, both the risk-neutral

and objective distributions can be combined to jointly estimate the market

price(s) of risk.

Note the minimization in equation (4.9), where the implied option

103

model volatility and structural parameters are recovered from minimizing the

difference between actual price and implied model price. These risk-neutral

parameter estimates can then be put into the model to generate option val-

ues for any moneyness/maturity combination. The option value can then be

inverted using the Black model to solve for

σ̃it, Imp = f (σ̂t, κ, ξ, θ, ρ) (4.10)

where f (·) is obtained by running the parameters κ, ξ, θ, ρ through the closed

form stochastic volatility option model16 and then inverting the option price

using the Black model. The subscript i, t denote the moneyness and time

dimension. The instantaneous volatility σ̂t is unobservable and must be es-

timated, which directly links the estimated implied volatility to the latent

factor. For each point in time and moneyness there is a corresponding ob-

servable σit,Imp, allowing for direct comparison between the model dependent

risk-neutral estimates of BIV volatility and the observable BIV. This implied

volatility comes from inverting the actual option price using the Black model.

The second equation used in estimation comes from the statistical

model analogous to the data-generating process in equations (4.1) - (4.2):

dS = (r + λSσt)S dt+ σt S dzS (4.11)

dσ2 =[κ(θ − σ2

t

)+ λσξσ

2]dt+ ξσt dzσ (4.12)

16In this example, only the stochastic volatility parameters are shown, since the initialconcern is just with the market price of volatility risk. When the other risk premium areestimated, model SVJ, SVJDJ will be used.

104

For given parameters {λS, σ̂t, κ, θ, λσ, ξ, ρ} , eqs. (4.11) - (4.12) will

produce a range of terminal values ST . The terminal values are generated

using quasi-Monte Carlo simulation, simulating the equations given in (4.11)

- (4.12)17. The Brownian motions are drawn from a N ∼ (0,√t) distribution

and the system is shocked daily. The simulation is generated 1000 times to

guarantee efficiency. From these terminal values the realized standard devia-

tion σ̃t,Realized is given by

σ̃t,Realized = g (λS, σ̂t, κ, θ, λσ, ξ, ρ) =1√T

STDEV

(lnST

S0

), (4.13)

where STDEV is the standard deviation operator

√√√√ 1

N − 1

N∑n=1

(xn − x)2

and x̄ is mean of the log daily return.

The ex-post realized volatility for that same 30-day period, to which

the RHS of equation (4.13) is set equal, is obtained from the realized-return

series over the given month

σt,Realized =

√√√√ 1

T − 1

T∑t=1

(st − s)2, (4.14)

where st = lnSt

St−1

, s ≡ 1

T

∑t

st.

Similar to the case for implied volatilities, I am able to generate real-

ized volatility dependent on the model parameters and have a actual measure

17The random draws were done using a Sobol sequence. The efficiency of estimationimproves from a standard error of 1√

nto 1

n

105

of volatility from the ex-post measure given in equation (4.13). Notice that

realized volatility is also dependent on instantaneous volatility σ̂t. By using

both the realized and implied volatility estimates, the market prices of risk

can be computed through the minimization of the difference between model

inferred volatilities and actual volatilities.

4.6 Proposed Algorithms

4.6.1 Parameter Estimation, including Market Price of Risk

The parameters I seek to solve for are {σ̂t, λs, λσ} , where λσ is the

market price of volatility risk in equation (4.12). Whereas λs and λσ are time-

invariant constants, σ̂t is the instantaneous volatility, and thus is different

from one time period to the next. For each point in time, there is an ex-post

realized volatility measure σt,Realized and Black implied volatility σt, i, Imp

from option prices over i strike prices. Using both measures of volatility, the

unknown parameters are estimated using the objective function

min{σ̂t, λs, λσ}

∑i,t

{ [f (σ̂t, κ, ξ, θ, ρ)− σt, i, Imp

]2+[g (λS, σ̂t, κ, θ, λσ, ξ, ρ)− σt,Realized

]2 }(4.15)

where f (·) is obtained via the inverted Black implied volatility from the model

dependent closed form price given in equations (4.5) - (4.7) and g (·) is obtained

106

by running a set of parameters through the simulation equations (4.11) - (4.12)

and (4.14). Eq. (4.15) may be amenable to GMM-style reformulation by noting

the covariation between f (·) and g (·) . Since there are multiple observations

of BIV for any given point in time, I minimize the difference between the

estimated realized and implied volatilities for both actual realized and implied

volatilities. This is done for each point in time, and the resulting parameters

are the average of the daily estimates from the objective function above.

The initial values for the non-linear estimation procedures are:

σt = σt, Imp

{κ, θ, ξ, ρ} = Implied parameters from SV model fit

λσ = 0

λS = 0

The estimation procedure was run on three models, SV, SVJ, and

SVDJ, to recover the market prices of risk. The return and volatility-jump

sizes were generated from the structural parameters µ, µj and σj. At each

point in time, to generate σt,Realized in the presence of jumps, the jump size

was quasi-randomly drawn from a normal distribution with the above mean

and standard deviation over the 1000 simulated paths. The arrival rates, λx

and λy, are adjusted for the market prices of jump risk, λj and λjv respectively,

such that a return-jump will arrive if,

λx(1− λj)4t ≥ B (4.16)

107

where B is drawn from a uniform∼(0,1) distribution. The correction for the

drift is given by λx(1−λj)J4t where J is the jump size drawn from the normal

N ∼ (µ, σj).

The Monte Carlo simulation is bounded such that the price and volatil-

ity cannot go below zero and the option values are calculated using the closed

form solutions specified in equations (4.5)-(4.7). The results of the minimiza-

tion of (4.15) can be found in table 52.

4.6.2 Results

For each model tested, the market price of volatility risk is negative and

significant in all cases. When controlling for return-jumps, and subsequently

for volatility-jumps, the estimate(s) for market price of volatility risk is reduced

as is the standard error of the estimate. For the gas markets, ignoring jumps

forces the underlying parameters ξ and ρ to capture the skewness and kurtosis

in the option prices, resulting in upward-biased values for these parameters.18

Since the market price of volatility risk, λσ, is linked to these underlying

values, it should be no surprise to see a much higher estimate, -17.96, than

that when return-jumps are included. Including volatility-jumps does not

change the estimate significantly from the SVJ model. The results when jumps

are included are very similar to those found in the earlier section when only

ATM implied volatilities were used in estimating the parameter. In fact, this

appeals to the intuition surrounding the dynamics of option valuation. Jumps

18refer to table 26 for parameter values.

108

are necessary to capture the behavior of the tails of the implicit distribution,

and provides better model performance in capturing the cross-section of option

prices. In the prior section, the tails were ignored, and estimates for the market

price of volatility risk for each of the months were between -8.77 and -3.46. In

this estimation, since there is a limited time-series, all months were combined,

the estimates for λσ when controlling for return jumps and return and volatility

jumps are -5.15 and -4.92 respectively. This result in particular reveals the

necessity for a having a negative market price of volatility risk to reconcile the

difference between the implied and realized distributions.

By comparison, the market price of risk, λs, is much tougher to esti-

mate due to lengthy time-series requirements to overcome significant variation

in the data. For example, in equities, if I assume λs to be .41, and the average

annual volatility is 20%, then approximately 50 years of data are needed to

arrive at significant estimates. Using the cross-section of option prices reduces

the data requirements, but as shown earlier, the volatility within the natural

gas markets is much more severe than the equities markets. The price risk

premiums found were all statistically insignificant and SVJ model suggest a

positive risk premia as compared to the SV and SVDJ models. These results

are not surprising, and lend little resolve to the ongoing debate between re-

searchers about the direction and magnitude of the market price of risk for

commodities. With the volatility observed in 1999 and 2000, it may take

several more years of data and reduced bid/ask spreads to achieve statistical

significance in either direction.

109

While not a major a concern, the results for the market price of jump

intensity risk for return and volatility-jumps show the significant premium

place on jumps in this market. To interpret the results, let us assume that a

risk-neutral jump arrives at a rate of 1 per year. If we take the SVJ model as

given, then a realized jump arrives at a rate of approximately 1 per every 2

years. For the SVDJ model, a realized return-jump arrives at 73% of the rate

of an implied return-jump. For volatilities jumps, the realized arrival rate is

51% of the implied arrival rate. This helps explain the significant skew/smile

observed in the cross-section of option prices. Consumers are concerned about

price spikes/jumps, and are willing to pay large premiums to hedge themselves

against large upturns/downturns in the market. As compared to equities, this

lends justification to why ITM and OTM options are expensive relative to

ATM options.

4.7 Conclusion

While not a surprise, natural gas implied risk-neutral parameters show

little similarity as compared to their equity counterparts. The correlation

between the processes is positive, there is positive mean jump size, and the

variation of volatility is almost 5 times higher. Using the latest additions

to the option modeling framework, the findings here suggest that an option

model that incorporates independent volatility and return-jumps is best able

to capture the cross-sectional and time-series dynamics of option prices. Incor-

porating a TSOV component had little effect on improving model performance,

110

but had a statistically significant impact on options that were close to expi-

ration. Given the significant and observable TSOV in natural gas contracts,

the results for model fit may seem unexpected, but the estimation procedure

minimized over the cross-section of daily option prices versus the time series,

reducing the potential impact of the TSOV parameter. Examining the season-

ality and yearly effects demonstrated the potential implications a cold winter,

hot summer, or energy crisis had on the parameters. Clearly, these effects were

magnified in the 1999, 2000 prices, where volatility variation was almost an

order of magnitude higher.

Through the minimization of equation (4.15), the market price of volatil-

ity risk was found to be highly negative and significant. These results were

very similar to those found through the calibration technique in section 3.3.

This premium is tied directly to the variation in volatility, which is signifi-

cantly higher than that found for equities. Selling options is a way to capture

the premium, as investors are willing to hedge against volatility variation by

either buying puts or calls. This protection is expensive, and as shown by

Eraker (2001), leads to equity Sharpe ratios six times that found for trading

equities. These ratios are close to 10 times that found for equities, but the nat-

ural gas markets are almost twice as volatile, and protection against volatility

change will ultimately be more expensive. Disappointingly, pinning down a

market price of risk for natural gas proved fruitless, as the degree of volatility

in the market and length of the data prevented significant estimates. However,

using this technique will further researchers’ efforts in future, due to market

111

stabilization and the availability of more usable data. Hopefully, solving the

magnitude and direction of the market price of risk is just observations away.

As for the main goal of this work, establishing a significant and negative

market price of volatility risk, all results clearly indicate the degree to which

this premium matters in the market. Through relating the bias in Black-

Scholes/Black implied volatility to realized-term volatility, to the estimation

of risk-neutral structural parameters, all findings suggest a negative volatility

risk premium. Understanding how investors place premiums on volatility helps

to solve phenomena such as the volatility smile/skew in the cross-section of

option prices, the reason why option traders like to be short, and why implied

volatility is upward bias predictor of future realized-term volatility.

112

Tables and Figures

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ugus

tw

hile

the

expo

nent

ialha

sbe

stov

eral

lfit

for

Janu

ary.

How

ever

,th

etw

om

onth

sw

ith

larg

eT

SOV

inJa

nuar

yw

here

impl

ied

vari

ance

sar

ecl

ose

to20

0%ar

efit

ted

best

wit

ha

reci

proc

alfu

ncti

on.

Ja

nu

ary

Im

pli

ed

Va

ria

nc

e

0.0

0%

50

.00

%

10

0.0

0%

15

0.0

0%

20

0.0

0%

25

0.0

0%

12

81

08

88

68

48

28

8

Da

ys

till M

atu

rity

Implied Varaince

Fig

ure

4:Jan

uar

yN

atura

lG

asC

ontr

acts

Implied

Vol

atility

117

The

Fig

ures

4an

d5

show

the

impl

ied

vari

ance

sof

Janu

ary

and

Aug

ust

opti

onco

ntra

cts.

The

reci

proc

alfu

ncti

onfit

sA

ugus

tw

hile

the

expo

nent

ialha

sbe

stov

eral

lfit

for

Janu

ary.

How

ever

,th

etw

om

onth

sw

ith

larg

eT

SOV

inJa

nuar

yw

here

impl

ied

vari

ance

sar

ecl

ose

to20

0%ar

efit

ted

best

wit

ha

reci

proc

alfu

ncti

on.

Au

gu

st

Imp

lie

d V

ari

an

ce

0.0

0%

20

.00

%

40

.00

%

60

.00

%

80

.00

%

10

0.0

0%

12

0.0

0%

14

0.0

0%

12

81

08

88

68

48

Da

ys

till M

atu

rity

Implied Variance

Fig

ure

5:A

ugu

stN

atura

lG

asC

ontr

acts

Implied

Vol

atility

118

Fig

ures

6an

d7

show

the

resu

lts

ofth

eM

onte

Car

losi

mul

atio

nov

erth

egi

ven

para

met

ers

and

the

resu

ltin

gcr

oss-

sect

iona

lpa

tter

nof

Bla

ck-S

chol

es/B

lack

Impl

ied

Vol

atili

ty

Co

mpara

tive S

tati

cs

for

the B

ias i

n B

SIV

for

an E

quit

y P

rocess

Ch

an

ge

in

Vo

lati

lity

0.0

0%

1.0

0%

2.0

0%

3.0

0%

4.0

0%

5.0

0%

6.0

0%

7.0

0%

8.0

0%

9.0

0%

10.0

0%

0.9

11.1

Str

ike

/Sp

ot

Bias

Theta

=20%

Theta

=30%

Theta

=40%

Cha

ng

e i

n M

atu

rit

y

-1.5

0%

-1.0

0%

-0.5

0%

0.0

0%

0.5

0%

1.0

0%

1.5

0%

2.0

0%

2.5

0%

Strik

e/S

pot

Bias

1 m

onth

1/2

ye

ar

1 y

ea

r

Ch

an

ge

in

ξ ξξξ

-2.0

0%

-1.0

0%

0.0

0%

1.0

0%

2.0

0%

3.0

0%

4.0

0%

5.0

0%

6.0

0%

0.9

11

.1

Str

ike

/Sp

ot

Bias

Xi=

.3

Xi=

.7C

ha

ng

e i

n λ

σλ

σλ

σλ

σ

-2.0

0%

-1.0

0%

0.0

0%

1.0

0%

2.0

0%

3.0

0%

4.0

0%

0.9

11

.1

Str

ike/S

pot

Bias1/2

ye

ar, -2

MP

VR

, .3

Xi

1/2

ye

ar, -.5

MP

VR

, .3

X

1/2

ye

ar, 0

MP

VR

, .3

X

Fig

ure

6:C

ross

-sec

tion

BSIV

plo

ts

119

Fig

ures

6an

d7

show

the

resu

lts

ofth

eM

onte

Car

losi

mul

atio

nov

erth

egi

ven

para

met

ers

and

the

resu

ltin

gcr

oss-

sect

iona

lpa

tter

nof

Bla

ck-S

chol

es/B

lack

Impl

ied

Vol

atili

ty

Ch

ange

in

ξ

ξ ξ

ξ w

ith

hig

h λ

σ λ

σ λ

σ λ

σ

0.0

0%

2.0

0%

4.0

0%

6.0

0%

8.0

0%

10.0

0%

12.0

0%

0.8

0.8

40.8

80.9

20.9

61

1.0

41.0

81.1

21.1

61.2

Str

ike

/Sp

ot

Bias

Xi=

.7

Xi=

.3

Co

mp

ara

tiv

e S

tati

cs

for

the B

ias

in B

IVfo

r th

e C

om

mo

dit

y P

rocess

Ch

an

ge i

n λ

σλ

σλ

σλ

σ

-2.0

0%

0.0

0%

2.0

0%

4.0

0%

6.0

0%

8.0

0%

10.0

0%

0.8

0.8

40.8

80.9

20.9

61

1.0

41.0

81.1

21.1

61.2

Str

ike

/Sp

ot

Bias

MP

VR

=-.

5

MP

VR

=-2

Ch

an

ge

in

Vo

lati

lity

0.0

0%

2.0

0%

4.0

0%

6.0

0%

8.0

0%

10.0

0%

12.0

0%

0.8

0.8

40.8

80.9

20.9

61

1.0

41.0

81.1

21.1

61.2

Str

ike

/Sp

ot

Bias

Vo

lati

lity

=2

0%

Vo

lati

lity

=4

0%

Cha

nge

in ξ ξξξ

-1.0

0%

0.0

0%

1.0

0%

2.0

0%

3.0

0%

4.0

0%

5.0

0%

6.0

0%

7.0

0%

0.8

0.8

40.8

80.9

20.9

61

1.0

41.0

81.1

21.1

61.2

Str

ike

/Sp

ot

Bias

Xi=

.7

Xi=

.3

Fig

ure

7:C

ross

-sec

tion

BIV

plo

ts

120

Figure 8 demonstrates the simulation within a simulation technique. The expandedsection shows one point in time and the 30 day simulations done from that pointgenerating option prices and realized volatility.

$0.00

$50.00

$100.00

$150.00

$200.00

$250.00

$300.00

$350.00

$400.00

1 365 729 1093 1457 1821

Days since inception

"price with-.5 mpvr"

price with no mpvr

Price with -2 mpvr and .5 Xi

Simulation: From Instantaneous to 30-Day Term Volatility

46

47

48

49

50

51

52

53

54

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

Figure 8: Simulation within a simulation technique

121

Figures 9 and 10 show Black implied volatility (BIV) plots for long-term naturalgas options for the 2001 and 2002 expiration contracts. The circle plots are BIVfrom call options while the square plots are puts. The three models tested are theSV model (the dashed line), the SVJ model (the dotted line), and the SVDJ model(the solid line). The time to maturity is ≥ 180 days.

Figure 9: BIV plots for long-term 2001 contracts

Figure 10: BIV plots for long-term 2002 contracts

122

Figures 11 and 12 show Black implied volatility (BIV) plots for medium-term naturalgas options for the 2001 and 2002 expiration contracts. The circle plots are BIVfrom call options while the square plots are puts. The three models tested are theSV model (the dashed line), the SVJ model (the dotted line), and the SVDJ model(the solid line). The time to maturity is 60− 180 days.

Figure 11: BIV plots for medium-term 2001 contracts

Figure 12: BIV plots for medium-term 2002 contracts

123

Figures 13 and 14 show Black implied volatility (BIV) plots for short-term naturalgas options for the 2001 and 2002 expiration contracts. The circle plots are BIVfrom call options while the square plots are puts. The three models tested are theSV model (the dashed line), the SVJ model (the dotted line), and the SVDJ model(the solid line). The time to maturity is ≤ 60 days.

Figure 13: BIV plots for short-term 2001 contracts

Figure 14: BIV plots for short-term 2002 contracts

124

Table 1: Descriptive statistics for the S&P 100 and S&P 500

IV is the constructed 30 day implied volatility estimated from either Bloomberg or VIX. RV is the estimatedrealized volatility over the next 30 days returns.

Index Volatility N mean Stdev Max Min Skew Kurt

OEX Full Sample IV 4183 21.18% 7.95% 150.19% 9.04% 3.795 44.186RV 4183 15.33% 9.04% 100.58% 4.82% 4.411 36.182

Pre-Oct 1987 IV 441 21.23% 2.91% 31.46% 15.91% 0.574 2.979RV 441 16.75% 12.84% 99.38% 9.12% 5.390 32.829

Post-Oct 1987 IV 3723 21.00% 7.32% 81.24% 9.04% 1.281 6.451RV 3723 14.87% 7.12% 72.26% 4.82% 1.685 7.518

SPX IV 1958 18.95% 5.51% 42.41% 8.16% 0.556 3.951RV 1938 16.11% 7.06% 44.18% 4.82% 0.971 4.085

125

Tab

le2:

Gas

Con

trac

ts

Des

crip

tive

statist

ics

ofdaily

retu

rns

for

natu

ralgas

futu

res

contr

act

s

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Aver

age

0.0

435%

0.0

238%

0.0

327%

0.0

451%

0.0

582%

0.0

552%

0.0

578%

0.0

444%

0.0

478%

0.0

488%

0.0

481%

0.0

41%

Std

ev25.9

0%

27.9

3%

27.3

7%

25.7

4%

24.7

8%

24.4

9%

24.6

7%

24.7

5%

25.6

3%

26.5

8%

25.0

9%

24.3

1%

Max

15.9

9%

17.0

6%

14.7

1%

10.2

8%

10.0

6%

9.7

3%

9.4

6%

10.3

0%

12.0

8%

11.6

4%

11.1

8%

11.0

1%

Min

-13.4

7%

-14.7

3%

-15.3

7%

-10.7

0%

-7.9

9%

-7.8

4%

-9.4

6%

-9.0

8%

-10.0

4%

-10.7

0%

-8.7

1%

-10.0

3%

Skew

0.2

5-0

.06

-0.1

6-0

.02

0.0

90.0

20.0

10.0

10.0

50.0

70.1

3-0

.06

Kurt

9.4

811.3

67.9

84.2

63.8

83.8

64.1

14.3

14.6

94.9

34.9

05.3

6

126

Table 3: Number of days with greater than 5% price movementsYear Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total1991 0 0 1 1 1 1 1 1 3 2 0 0 111992 0 0 2 2 3 1 2 2 2 4 2 1 211993 0 2 0 4 4 0 0 0 0 0 0 0 101994 1 3 3 0 0 0 0 0 0 0 0 0 71995 2 2 1 2 1 1 1 0 1 1 1 0 131996 4 6 10 4 1 0 0 1 2 3 6 9 461997 9 11 6 6 6 1 1 1 2 N/A 7 5 551998 2 1 1 1 2 0 2 2 3 9 5 3 311999 4 4 1 2 1 0 0 2 2 4 2 3 252000 4 4 3 0 0 2 4 4 8 6 7 10 522001 15 13 15 10 8 8 9 8 7 8 12 11 1242002 13 14 12 15 16 17 19 15 18 17 12 7 1752003 4 4 5 8 8 8 6 4 4 4 4 3 622004 3 1 1 2 2 1 1 1 1 0 0 0 132005 0 0 0 0 0 0 0 0 0 0 0 0 02006 0 0 0 0 0 0 0 0 0 0 0 N/A 02007 0 0 0 0 0 0 0 0 0 N/A N/A N/A 0Total 61 65 61 57 53 40 46 41 53 58 58 52 645

Table 4: Number of days with greater than 10% price movementsJan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total

5 9 6 1 1 0 0 1 1 2 2 1 29

127

Table 5: Bias in BSIV in S&P 100 contracts

Regression of VIX volatility on S&P 100 (OEX) realized term volatility. Sample is monthly data fromJan-1986 to Aug-2002. Each regression is specified in level of volatility except the last regression, which isdone in log-levels. Regression run on ht = α0 + αiit + εt. σRV is the realized volatiltiy, σRVt−1 is priormonth realized volatility, and σIV is the implied volatility. The DW-Statistic is not significantly differentfrom 2 for each regression.

Model: ht = α0 + αiit + εt

OLS Newey-West OLS Newey-West IV IV

Dependent σRV σRV σRV σRV σRV LN(σRV )

σIV 0.735 0.605 0.774 0.597 0.694(9.31)** (6.38)** (5.69)** (4.52)** (3.57)**

σRVt−1 -0.038 0.008 0.013

(0.35) (0.11) (0.1)LN(σIV ) 1.061

(4.79)**LN(σRVt−1 ) -0.003

(0.02)Constant 0 0.025 -0.003 0.026 0.006 -0.278

(0.00) (1.24) (0.14) (1.18) (0.26) (2.05)*Observations 200 4183 199 4161 199 199R-squared 0.3 0.31 0.3 0.51

Absolute value of t statistics in parentheses* significant at 5%; ** significant at 1%Newey-West regression with 22 lagsOLS is done at a monthly frequencyInstrumental variables (IV) are one month prior implied volatility and realized volatility

128

Table 6: Bias in BSIV in S&P 500 contracts

Regression of implied volatility on S&P 500 realized term volatility. Sample isMonthly data from Oct-1994 to July-2002. Each regression is specified in levelof volatility except the last regression, which is done in log-levels. Regressionrun on ht = α0 + αiit + εt. σRV is the realized volatiltiy, σRVt−1 is prior monthrealized volatility, and σIV is the implied volatility. The DW-Statistic is notsignificantly different from 2 for each regression.

Model: ht = α0 + αiit + εt

OLS Newey-West OLS Newey-West IV IV

Dependent σRV σRV σRV σRV σRV LN(σRV )

σIV 0.645 0.638 0.402 0.397 0.944(4.96)** (5.98)** (3.03)** (4.62)** (4.50)**

σRVt−1 0.387 0.415 0.224

(4.11)** (5.52)** (1.99)*LN(σIV ) 1.042

(5.03)**LN(σRVt−1 ) 0.23

(2.07)*Constant 0.042 0.041 0.025 0.02 -0.048 0.331

(1.71) (2.18)* (1.08) (1.55) (1.47) (1.27)Observations 93 1938 92 1916 92 92R-squared 0.21 0.33 0.21 0.43

Absolute value of t statistics in parentheses* significant at 5%; ** significant at 1%Newey-West regression with 22 lagsOLS is done at a monthly frequencyInstrumental variables are one month prior implied volatility and realized volatility

129

Table 7: TSOV Specification Fit

The first row of each contract represents the exponential fit, followed by thequadratic, and finally the reciprocal. Each cell is the results of the minimiza-tion of equation 12, and those in bold show the model with the best fit foreach monthly contract.

Month Out-of-Sample 1day Out-of-Sample 1day Out-of-Sample 5day behind In-Sample

Jan 12.90 16.02 16.04 14.6919.42 25.77 25.67 24.0334.20 31.81 25.36 31.09

Feb 15.12 19.36 21.97 14.6620.63 29.26 29.51 23.2386.75 75.48 58.89 71.50

Mar 27.39 30.19 33.06 25.1129.70 32.50 34.20 27.07

101.02 104.06 86.44 96.59

Apr 11.08 13.63 15.81 10.8610.10 13.80 16.16 11.3836.44 30.23 26.07 24.49

May 4.65 5.72 6.63 4.563.93 5.36 6.28 4.42

14.19 11.77 10.15 9.54

Jun 4.44 5.45 6.33 4.344.14 5.66 6.62 4.66

11.21 9.30 8.02 7.53

Jul 7.81 9.61 11.15 7.657.76 10.60 12.41 8.745.93 6.65 5.74 5.39

Aug 14.11 17.35 20.13 13.8314.74 20.15 23.59 16.618.52 8.66 7.47 7.02

Sep 13.84 17.02 19.74 13.5615.98 21.83 25.56 18.019.15 10.80 9.32 8.75

Oct 8.94 10.99 12.75 8.7611.03 15.08 17.65 12.4314.07 11.67 10.07 9.46

Nov 18.86 23.18 26.89 18.4718.74 25.60 29.98 21.1133.04 27.40 23.64 22.21

Dec 10.04 12.35 14.32 9.8413.86 18.95 22.18 15.6243.38 35.98 31.04 29.16

130

Tab

le8:

Bia

sin

BIV

inN

atura

lG

asFutu

res

Reg

ress

ion

ofT

SO

Vad

just

edB

lack

Implied

Vol

atility

onN

atura

lG

asFutu

res

Rea

lize

dTer

mV

olat

ility.

Dat

ais

from

Mon

thly

Con

trac

tsfr

om19

95-2

004.

The

DW

-Sta

tist

icis

not

sign

ifica

ntl

ydiff

eren

tfr

om2

for

each

regr

essi

on.σ

RV

isth

ere

aliz

edvo

lati

ltiy

RV

t−1

isprior

mon

thre

aliz

edvo

lati

lity

,an

IV

isth

eim

plied

vola

tility

.T

he

dep

enden

tva

riab

leis

the

mon

thlyσ

RV

Mod

el1:

ht

0+

α1i t

+ε t

Mod

el2:

ht

0+

α1i t

2h

t−1ε t

Model1

Dependent

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

σI

V1.1

61

1.2

79

1.3

32

1.5

15

1.4

17

0.7

69

1.1

27

1.2

59

1.2

41.2

95

1.1

02

1.0

8(1

0.1

2)*

*(1

7.8

2)*

*(1

3.2

0)*

*(1

0.0

8)*

*(1

1.6

5)*

*(9

.59)*

*(8

.66)*

*(1

4.6

1)*

*(1

1.7

0)*

*(1

2.5

7)*

*(1

1.0

7)*

*(1

3.6

6)*

-0.1

26

-0.1

66

-0.1

78

-0.2

01

-0.1

48

0.0

42

-0.0

81

-0.1

15

-0.1

12

-0.1

32

-0.0

87

-0.1

1(3

.53)*

*(7

.39)*

*(5

.11)*

*(4

.60)*

*(4

.18)*

*(1

.82)

(2.0

1)*

(4.2

8)*

*(3

.30)*

*(4

.03)*

*(2

.63)*

(3.8

7)*

*O

bs

92

92

106

90

85

117

91

85

95

88

90

103

R-s

quare

d0.6

50.6

40.7

30.5

70.6

30.5

20.6

10.6

80.6

50.6

60.6

60.6

9

Model2

Dependent

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

σI

V0.9

55

0.8

52

1.4

12

1.5

05

1.3

69

0.3

78

0.9

87

1.3

72

1.3

76

1.3

61.2

26

0.9

16

(6.4

3)*

*(5

.76)*

*(5

.80)*

*(4

.73)*

*(5

.99)*

*(2

.85)*

*(3

.05)*

*(5

.88)*

*(6

.66)*

*(5

.87)*

*(6

.23)*

*(6

.50)*

RV

t−

10.2

44

0.3

92

-0.0

50.0

14

0.0

15

0.5

07

0.1

23

-0.1

06

-0.0

3-0

.084

-0.1

12

0.2

13

(1.6

7)

(2.7

3)*

*(0

.24)

(0.0

8)

(0.1

0)

(4.1

8)*

*(0

.60)

(0.6

7)

(0.2

2)

(0.5

5)

(0.7

6)

(1.8

3)

α-0

.11

-0.1

14

-0.1

96

-0.2

02

-0.1

34

0.0

27

-0.0

67

-0.1

23

-0.1

53

-0.1

3-0

.102

-0.1

08

(3.1

4)*

*(3

.83)*

*(4

.51)*

*(3

.30)*

*(3

.06)*

*(1

.21)

(1.1

3)

(3.0

8)*

*(3

.76)*

*(2

.91)*

*(2

.57)*

(3.5

0)*

*O

bs

82

78

96

78

74

100

78

71

84

77

79

94

R-s

quare

d0.6

60.7

70.7

20.5

50.6

0.6

20.5

90.6

50.7

0.6

40.6

70.7

2

Abso

lute

valu

eof

tst

atis

tics

inpar

enth

eses

*si

gnifi

cant

at5%

;**

sign

ifica

nt

at1%

131

Table 9: Perfect and Zero Correlation Case

Table below shows the degree of bias in BSIV/BIV of the extreme cases of perfect and zero correlationbetween the price and volatility process. Panel A shows the perfect correlation case and Panel B the zerocorrelation case. For the gas process the correlation is positive and the market price of risk is -.5; for theequity process it is negative and the market price of risk is .41. κ (mean reversion) and ξ (volatility of thevolatility process) are 7 and .3 for both simulations.

Equity Panel A Panel Bλσ=.41 λσ=0 λσ=.41

θ=15% θ=20% θ=30% θ=15% θ=20% θ=30% θ=15% θ=20% θ=30%K/S K/S0.9 3.74% 3.50% 3.07% 0.9 0.75% 0.47% 0.30% 1.04% 0.72% 0.69%

3.91% 3.50% 3.09% 0.73% 0.51% 0.32% 0.95% 0.74% 0.71%

1 0.73% 0.88% 1.10% 1 0.11% 0.17% 0.23% 0.33% 0.47% 0.67%0.73% 0.88% 1.11% 0.10% 0.16% 0.22% 0.33% 0.47% 0.66%

1.1 -1.98% -2.03% -0.83% 1.1 0.61% 0.43% 0.34% 0.81% 0.65% 0.76%-2.00% -2.02% -0.83% 0.70% 0.43% 0.34% 0.86% 0.69% 0.78%

Gasλσ=-.5 λσ=0 λσ=-.5

θ=30% θ=30% θ=30%K/S K/S0.9 -0.70% 0.9 0.99% 1.52%

-0.71% 1.00% 1.52%

1 1.47% 1 0.97% 1.42%1.45% 0.97% 1.42%

1.1 3.19% 1.1 0.98% 1.46%3.18% 0.97% 1.48%

132

Tab

le10

:E

quity

Pro

por

tion

alV

olat

ility

Model

wit

hM

arke

tP

rice

ofVol

atility

Ris

k

Res

ult

sof

sim

ula

tion

done

on

giv

enpara

met

ervalu

es.

Each

entr

yhas

are

sult

for

aca

ll(t

op)

and

put(

bott

om

).λ

Jis

the

mark

etpri

ceof

jum

pri

sk;λ

σis

the

mark

etpri

ceofvola

tility

risk

.κ,θ

and

ξare

giv

enin

pri

or

sim

ula

tions.

The

start

ing

stock

valu

eis

$50

λJ

0.5

0.5

0.8

0.8

0.5

0.5

0.8

0.8

0.5

0.5

0.8

0.8

λσ

-2-0

.5-2

-0.5

-2-0

.5-2

-0.5

-2-0

.5-2

-0.5

Tim

e1

month

1/2

year

1year

Str

ike

Str

ike

Str

ike

40

11.6

8%

10.3

4%

12.2

0%

10.7

9%

40

6.5

9%

2.6

4%

7.1

2%

3.2

2%

40

4.3

0%

-0.8

1%

5.0

0%

0.0

5%

12.3

6%

10.9

3%

12.9

0%

11.4

7%

6.6

5%

2.8

1%

7.3

0%

3.4

0%

4.5

0%

-0.6

5%

5.1

7%

0.2

5%

42

8.8

5%

7.4

3%

9.3

7%

7.9

4%

42

6.1

4%

2.2

6%

6.8

2%

2.9

1%

42

3.7

9%

-1.0

8%

4.7

0%

-0.5

2%

8.6

1%

7.1

9%

9.0

9%

7.7

1%

6.2

0%

2.1

8%

6.6

8%

2.7

7%

3.9

4%

-1.1

0%

4.6

8%

-0.3

7%

44

6.0

5%

4.6

3%

6.5

0%

5.1

4%

44

5.7

3%

1.6

2%

6.2

1%

2.3

1%

44

3.5

2%

-1.2

4%

4.4

8%

-0.7

3%

6.1

7%

4.7

8%

6.6

7%

5.2

8%

5.6

5%

1.7

0%

6.3

0%

2.4

0%

3.6

9%

-1.3

4%

4.3

8%

-0.5

6%

46

4.6

7%

3.2

7%

5.1

8%

3.7

9%

46

5.2

0%

1.2

6%

5.7

0%

1.8

0%

46

3.5

9%

-1.6

5%

4.0

7%

-0.6

3%

4.5

9%

3.1

6%

5.1

1%

3.7

3%

5.2

7%

1.2

4%

5.7

8%

1.8

7%

3.6

4%

-1.5

3%

4.1

9%

-0.5

8%

48

3.4

7%

2.0

8%

3.9

6%

2.5

5%

48

4.7

3%

0.9

0%

5.4

8%

1.5

9%

48

3.2

7%

-1.7

7%

3.9

4%

-0.9

6%

3.4

9%

2.1

2%

4.0

0%

2.6

1%

4.7

9%

0.9

1%

5.3

7%

1.4

8%

3.1

7%

-1.6

6%

4.0

5%

-1.0

7%

50

2.7

2%

1.3

3%

3.2

9%

1.8

5%

50

4.6

3%

0.4

8%

4.9

4%

1.0

2%

50

3.2

5%

-2.0

1%

3.8

0%

-1.0

1%

2.7

2%

1.3

2%

3.2

4%

1.8

3%

4.5

1%

0.4

8%

4.9

9%

1.0

7%

3.2

3%

-1.9

3%

3.8

8%

-1.0

3%

52

2.1

8%

0.8

0%

2.6

6%

1.2

7%

52

4.1

0%

0.1

8%

4.6

6%

0.7

6%

52

2.7

8%

-2.3

4%

3.4

6%

-1.5

2%

2.1

6%

0.7

8%

2.6

6%

1.2

6%

4.1

7%

0.2

0%

4.7

3%

0.8

3%

2.8

8%

-2.3

4%

3.4

7%

-1.4

2%

54

1.7

2%

0.3

3%

2.2

0%

0.8

2%

54

3.7

7%

-0.1

4%

4.4

7%

0.5

8%

54

2.5

0%

-2.2

1%

3.5

0%

-1.7

5%

1.6

1%

0.2

2%

2.1

1%

0.7

0%

3.8

4%

-0.1

7%

4.3

9%

0.5

0%

2.6

7%

-2.3

4%

3.3

7%

-1.5

7%

56

1.4

9%

0.0

9%

1.9

4%

0.5

5%

56

3.5

9%

-0.5

0%

4.0

6%

0.1

5%

56

2.5

0%

-2.5

8%

3.1

4%

-1.6

8%

1.4

6%

0.0

1%

1.8

8%

0.5

1%

3.4

6%

-0.4

7%

4.1

3%

0.2

2%

2.5

6%

-2.4

7%

3.2

4%

-1.6

3%

58

1.4

2%

0.0

2%

1.8

8%

0.5

1%

58

3.4

0%

-0.6

3%

3.8

3%

-0.0

9%

58

2.4

1%

-2.8

0%

2.9

1%

-1.8

1%

1.4

9%

0.1

3%

1.8

8%

0.5

0%

3.4

4%

-0.6

9%

3.9

4%

0.0

2%

2.3

2%

-2.6

7%

3.0

4%

-1.9

0%

60

1.4

5%

0.0

5%

1.9

5%

0.5

1%

60

2.9

6%

-0.9

2%

3.6

8%

-0.2

3%

60

2.3

2%

-2.9

2%

2.8

7%

-1.9

3%

1.0

7%

-0.3

7%

1.6

2%

0.1

1%

3.0

6%

-0.8

4%

3.5

3%

-0.3

8%

2.2

5%

-2.8

4%

2.9

5%

-2.0

0%

133

Tab

le11

:E

quity

Pro

cess

Sto

chas

tic

Vol

atility

Tab

le

This

table

repre

sents

the

bia

sin

BSIV

over

realize

d-t

erm

vola

tility

thro

ugh

tim

eand

per

iods

of

hig

h,

med

ium

,and

low

vola

tility

.H

igh

spot

vola

tility

isat

30%

,m

ediu

msp

ot

vola

tility

is20%

,and

low

spot

vola

tility

isat

15%

.A

dditio

nally,

the

mark

etpri

ceofvola

tility

risk

(λσ)

and

the

vola

tility

ofvola

tility

pro

cess

are

vari

ed(ξ

)to

exam

ine

the

sensi

tivity

ofth

ebia

sto

the

under

lyin

gpara

met

ers.

The

start

ing

stock

pri

ceis

$50.P

anel

Ais

the

low

vola

tility

,Panel

Bis

the

med

ium

vola

tility

,and

Panel

Cis

the

hig

hvola

tility

.The

initia

lst

ock

pri

cew

as

$50,th

em

ean

rever

sion

was

7and

the

corr

elation

was

.53.

Thes

ein

itia

lst

art

ing

valu

esco

me

from

pri

or

findin

gs.

Pnael

Bom

mitte

d.

PanelA

PanelC

ξ.3

.7ξ

.3.7

λσ

-2-0

.50

-2-0

.50

λσ

-2-0

.50

-2-0

.50

1m

onth

1m

onth

45

4.0

6%

2.2

4%

2.5

5%

7.2

0%

6.5

3%

6.1

1%

45

3.4

6%

2.0

8%

1.5

7%

7.2

3%

4.2

9%

3.1

5%

3.7

7%

3.5

5%

3.2

9%

7.5

0%

6.4

7%

6.1

4%

3.4

6%

2.1

0%

1.5

9%

7.2

7%

4.2

7%

3.1

4%

50

0.8

5%

0.4

0%

0.2

5%

1.1

0%

0.2

0%

-0.1

9%

50

2.3

7%

0.9

7%

0.5

1%

4.5

9%

1.6

7%

0.5

3%

0.8

4%

0.3

9%

0.2

5%

1.1

0%

0.2

2%

-0.1

9%

2.3

7%

0.9

6%

0.5

2%

4.5

8%

1.6

8%

0.5

6%

55

0.2

9%

-0.4

4%

-0.3

6%

1.5

6%

0.8

3%

0.4

3%

55

1.4

2%

0.0

2%

-0.4

9%

2.5

1%

-0.3

6%

-1.5

1%

1.8

7%

-0.6

2%

-6.5

2%

2.2

1%

-6.1

6%

1.7

3%

1.4

4%

0.0

2%

-0.5

0%

2.5

1%

-0.3

8%

-1.4

7%

1/2

year

1/2

year

45

3.4

5%

2.3

7%

1.9

2%

6.1

0%

4.2

3%

3.2

2%

45

4.1

5%

0.2

2%

-1.3

5%

9.3

6%

3.3

6%

-0.0

6%

3.4

9%

2.3

1%

1.8

5%

6.0

5%

4.1

3%

3.1

5%

4.1

4%

0.2

5%

-1.3

8%

9.3

2%

3.2

9%

-0.0

8%

50

1.7

3%

0.5

5%

0.0

5%

2.7

3%

0.9

0%

-0.1

1%

50

3.6

0%

-0.3

2%

-2.0

1%

7.9

3%

1.9

8%

-1.3

5%

1.7

3%

0.5

6%

0.0

5%

2.6

5%

0.8

9%

-0.1

3%

3.6

1%

-0.3

6%

-2.0

2%

7.9

4%

1.9

9%

-1.3

4%

55

0.4

7%

-0.6

8%

-1.1

7%

1.0

7%

-0.6

9%

-1.7

3%

55

3.1

2%

-0.8

2%

-2.4

0%

6.8

5%

0.8

8%

-2.4

4%

0.4

8%

-0.7

0%

-1.2

0%

1.0

2%

-0.8

5%

-1.8

0%

3.1

4%

-0.7

9%

-2.4

1%

6.8

5%

0.9

2%

-2.4

4%

1year

1year

45

2.8

9%

1.5

6%

0.9

7%

5.2

8%

3.2

8%

2.0

6%

45

2.6

1%

-2.1

9%

-4.5

9%

8.4

3%

1.4

3%

-2.9

9%

2.8

2%

1.5

0%

0.9

1%

5.1

2%

3.1

5%

2.0

0%

2.5

7%

-2.2

2%

-4.6

3%

8.4

4%

1.3

9%

-2.9

9%

50

1.7

6%

0.4

8%

-0.1

6%

3.2

1%

1.2

0%

-0.0

1%

50

2.2

8%

-2.6

7%

-4.8

8%

7.7

4%

0.5

7%

-3.6

6%

1.7

6%

0.4

7%

-0.1

8%

3.1

4%

1.0

6%

-0.0

6%

2.2

7%

-2.6

9%

-4.9

0%

7.6

2%

0.5

6%

-3.7

8%

55

0.9

4%

-0.4

1%

-0.9

8%

1.6

8%

-0.2

6%

-1.5

4%

55

1.9

6%

-2.9

0%

-5.2

0%

6.9

9%

-0.0

3%

-4.5

0%

0.9

2%

-0.4

0%

-0.9

9%

1.6

0%

-0.3

5%

-1.6

7%

1.9

7%

-2.9

2%

-5.1

8%

6.9

2%

-0.1

3%

-4.5

7%

134

Tab

le12

:C

omm

odity

Pro

cess

Sto

chas

tic

Vol

atility

Tab

le

This

table

repre

sents

the

bia

sin

BIV

over

realize

d-t

erm

vola

tility

thro

ugh

tim

eand

per

iods

ofhig

h,m

ediu

m,and

low

vola

tility

for

the

gas

pro

cess

.H

igh

spot

vola

tility

isat

40%

,m

ediu

msp

ot

vola

tility

is30%

,and

low

spot

vola

tility

isat

25%

.A

ddit

ionally,

we

vary

the

mark

etpri

ceofvari

ance

risk

(λσ)

and

the

vola

tility

ofvola

tility

pro

cess

(ξ)

toex

am

ine

the

sensi

tivity

ofth

ebia

sto

the

under

lyin

gpara

met

ers.

The

start

ing

futu

res

pri

ceis

$50,th

em

ean

rever

sion

was

7and

the

corr

elati

on

was

-.53.

Thes

epara

met

ers

are

sim

ilar

toth

eeq

uity

valu

esex

cept

for

the

mark

etpri

ceofri

skand

corr

elati

on

whic

hare

both

neg

ative.

θis

the

level

tow

hic

hvola

tility

rever

tsand

Kis

the

stri

ke

pri

ce.

λσ

-2-2

-0.5

-0.5

-2-2

-0.5

-0.5

-2-2

-0.5

-0.5

ξ0.3

0.7

0.3

0.7

0.3

0.7

0.3

0.7

0.3

0.7

0.3

0.7

θ0.2

0.3

0.4

K40

1.3

5%

3.0

7%

0.3

1%

0.9

8%

0.7

0%

-0.5

1%

-0.7

5%

-3.2

0%

2.1

7%

3.1

2%

0.3

8%

-0.7

7%

1.3

5%

3.0

7%

0.3

1%

0.9

8%

1.1

8%

2.4

0%

-0.1

8%

-0.5

3%

2.3

2%

3.5

4%

0.5

0%

-0.3

6%

42

2.2

1%

4.1

7%

1.7

6%

1.0

2%

1.5

1%

2.6

1%

0.1

7%

-0.2

4%

2.7

2%

4.1

7%

0.8

9%

0.3

3%

0.7

3%

2.2

1%

-0.1

5%

0.1

0%

1.4

1%

2.3

6%

0.0

5%

-0.5

6%

2.6

7%

4.0

6%

0.8

4%

0.2

2%

44

0.1

4%

0.6

3%

-0.6

5%

-0.2

3%

1.6

2%

2.3

6%

0.2

4%

-0.5

9%

2.8

9%

4.3

8%

1.0

9%

0.5

7%

0.5

2%

1.5

2%

-0.4

3%

-0.4

0%

1.6

9%

2.5

0%

0.3

2%

-0.4

0%

2.9

4%

4.5

1%

1.1

3%

0.6

5%

46

0.7

4%

1.1

8%

-0.1

6%

-0.7

9%

1.9

8%

2.9

9%

0.6

1%

0.0

8%

3.1

6%

5.0

9%

1.3

6%

1.2

0%

0.7

2%

1.1

8%

-0.1

9%

-0.8

0%

1.9

7%

2.9

9%

0.6

0%

0.1

0%

3.1

6%

5.0

9%

1.3

6%

1.2

0%

48

1.2

2%

1.6

1%

0.3

1%

-0.3

0%

2.4

1%

3.7

8%

1.0

5%

0.8

8%

3.5

4%

5.7

9%

1.7

1%

1.9

2%

1.2

3%

1.6

4%

0.3

1%

-0.2

6%

2.4

2%

3.8

0%

1.0

5%

0.9

0%

3.5

4%

5.8

0%

1.7

2%

1.9

3%

50

1.7

9%

2.9

0%

0.8

9%

1.0

1%

2.7

7%

4.7

1%

1.4

2%

1.8

0%

3.7

8%

6.4

8%

1.9

7%

2.6

1%

1.7

8%

2.8

8%

0.8

8%

1.0

0%

2.7

7%

4.6

9%

1.4

2%

1.7

8%

3.7

7%

6.4

7%

1.9

6%

2.5

9%

52

2.4

2%

4.3

8%

1.5

1%

2.4

1%

3.2

2%

5.6

8%

1.8

6%

2.7

9%

4.1

4%

7.2

0%

2.3

4%

3.3

3%

2.4

3%

4.4

1%

1.5

1%

2.4

5%

3.2

2%

5.7

0%

1.8

6%

2.8

1%

4.1

5%

7.2

0%

2.3

5%

3.3

5%

54

2.9

2%

5.7

0%

2.0

2%

3.7

0%

3.5

1%

6.5

4%

2.1

7%

3.6

4%

4.3

3%

7.7

9%

2.5

2%

3.9

2%

2.9

3%

5.7

2%

2.0

4%

3.7

4%

3.5

2%

6.5

5%

2.1

7%

3.6

5%

4.3

3%

7.7

9%

2.5

2%

3.9

3%

56

3.4

7%

6.8

7%

2.5

6%

4.9

6%

3.9

6%

7.4

4%

2.6

0%

4.5

3%

4.7

4%

8.5

4%

2.9

1%

4.6

9%

3.4

7%

6.9

2%

2.5

8%

4.9

2%

3.9

6%

7.4

5%

2.6

0%

4.5

5%

4.7

3%

8.5

4%

2.9

1%

4.7

0%

58

3.9

0%

7.9

6%

2.9

6%

6.0

0%

4.1

8%

8.1

5%

2.8

2%

5.2

3%

4.8

3%

9.0

2%

3.0

2%

5.1

2%

3.8

6%

7.9

3%

2.8

9%

5.9

3%

4.1

7%

8.1

3%

2.8

1%

5.2

1%

4.8

4%

9.0

6%

3.0

1%

5.1

1%

60

4.3

6%

8.7

7%

3.4

7%

6.9

6%

4.5

3%

8.8

6%

3.1

6%

6.0

0%

5.1

1%

9.6

3%

3.3

5%

5.7

9%

4.2

4%

8.8

4%

3.3

4%

6.8

1%

4.4

8%

8.8

4%

3.1

2%

5.9

4%

5.1

1%

9.6

3%

3.3

3%

5.7

9%

135

Tab

le13

:E

quity

Jum

pTab

le

This

table

repre

sents

the

bia

sin

BSIV

rela

tive

tore

alize

dte

rmvola

tility

.T

he

pri

cepro

cess

ism

odel

as

eith

erpure

jum

p-d

iffusi

on

or

jum

p-d

iffusi

on

wit

hst

och

ast

icvola

tility

.T

her

eis

no

mark

etpri

ceofvola

tility

risk

inth

est

och

ast

icvola

tility

case

.Panel

Are

pre

sents

the

bia

sin

aca

lloption

while

Panel

Bex

am

ines

aput.

The

under

lyin

gvola

tility

inea

chca

se30%

and

jum

psi

zeis

-10%

.T

he

option

expir

esin

1m

onth

.W

ithin

each

Panel

,if

ST

VO

L=

0th

enth

ere

isno

stoch

ast

icvola

tility

,if

ST

VO

L=

1,th

enth

ere

isst

och

ast

icvola

tility

isth

ein

tensi

tyofju

mp

arr

ivaland

λJ

isth

em

ark

etpri

ceofju

mp

risk

.T

he

start

ing

stock

valu

eis

equalto

$50.

Valu

esfo

rth

eoth

erin

stanta

neo

us

para

met

ers

are

hel

dco

nst

ant

and

giv

enas

bef

ore

.

PanelA

PanelB

γ.5

.51

λJ

0.2

0.5

0.9

0.2

0.5

0.9

λJ

0.2

0.5

0.9

0.2

0.5

0.9

ST

VO

L=

0ST

VO

L=

045

0.7

1%

1.2

0%

1.4

2%

1.3

8%

1.7

1%

2.5

6%

45

0.8

1%

1.1

2%

1.4

2%

1.3

4%

1.8

7%

2.4

6%

50

0.4

3%

0.7

1%

0.8

9%

0.5

4%

1.0

3%

1.6

5%

50

0.4

1%

0.7

0%

0.9

4%

0.6

1%

1.0

1%

1.6

4%

55

0.1

8%

0.3

7%

0.7

5%

0.0

2%

0.5

9%

1.1

7%

55

0.1

7%

0.3

9%

0.7

2%

0.0

1%

0.5

9%

1.2

7%

ST

VO

L=

1ST

VO

L=

145

1.9

7%

2.2

6%

1.4

2%

2.5

2%

2.8

7%

2.5

6%

45

1.9

8%

2.3

0%

1.4

2%

2.5

1%

2.8

6%

2.4

6%

50

0.5

9%

0.9

0%

0.8

9%

0.7

3%

1.2

2%

1.6

5%

50

0.6

2%

0.8

7%

0.9

4%

0.7

4%

1.2

5%

1.6

4%

55

-0.5

4%

-0.3

4%

0.7

5%

-0.6

9%

-0.1

3%

1.1

7%

55

-0.5

9%

-0.3

4%

0.7

2%

-0.6

5%

-0.1

9%

1.2

7%

136

Tab

le14

:E

quity

Pro

por

tion

alV

olat

ility

Jum

pTab

le

This

table

repre

sents

the

bia

sin

BSIV

rela

tive

tore

alize

dte

rmvola

tility

.T

he

pri

cepro

cess

ism

odel

as

eith

erpro

port

ional

jum

p-d

iffusi

on

or

pro

port

ionalju

mp-d

iffusi

on

with

stoch

ast

icvola

tility

.T

her

eis

no

mark

etpri

ceofvola

tility

risk

inth

est

och

ast

icvola

tility

case

.Panel

Are

pre

sents

the

bia

sin

aca

llopti

on

while

Panel

Bex

am

ines

aput.

The

under

lyin

gvola

tility

inea

chca

se30%

and

jum

psi

zeis

-10%

.A

dditio

nally,

the

jum

psi

zeis

random

dra

wn

from

anorm

aldis

trib

uti

on.

See

above

table

for

furt

her

det

ails.

PanelA

PanelB

γ.5

.51

λJ

0.2

0.5

0.9

0.2

0.5

0.9

λJ

0.2

0.5

0.9

0.2

0.5

0.9

ST

VO

L=

0ST

VO

L=

045

1.0

2%

1.3

0%

1.6

3%

1.9

4%

2.3

3%

3.0

1%

45

1.1

0%

1.4

0%

1.7

4%

1.8

5%

2.2

9%

2.9

5%

50

0.2

5%

0.4

9%

0.7

7%

0.1

7%

0.5

9%

1.3

1%

50

0.2

7%

0.4

7%

0.8

3%

0.1

5%

0.6

7%

1.2

8%

55

0.1

6%

0.3

1%

0.6

0%

-0.1

4%

0.3

8%

1.0

9%

55

0.1

2%

0.2

5%

0.6

5%

-0.0

8%

0.3

8%

1.0

3%

ST

VO

L=

1ST

VO

L=

145

2.3

7%

2.6

4%

2.8

9%

2.9

1%

3.4

8%

4.1

6%

45

2.3

0%

2.5

6%

2.8

6%

2.9

3%

3.3

9%

4.1

2%

50

0.4

0%

0.6

4%

0.9

9%

0.4

6%

0.8

8%

1.6

1%

50

0.3

9%

0.7

0%

1.0

2%

0.4

4%

0.8

4%

1.6

1%

55

-0.6

9%

-0.4

2%

-0.0

4%

-0.7

0%

-0.4

2%

0.2

6%

55

-0.6

4%

-0.3

6%

-0.1

2%

-0.6

5%

-0.3

3%

0.3

7%

137

Table 15: Commodity Jump Table

This table represents the bias in BIV relative to realized term volatility for gas contracts. The futuresprocess is model as either pure jump-diffusion (Panel A) or jump-diffusion with stochastic volatility (PanelB). There is no market price of volatility risk in the stochastic volatility case. γ is the intensity of jumparrival and λJ is the market price of jump risk. The starting futures value is equal to $50. All otherparameters are fixed and initial values are the same as in prior simulations.

Panel A Panel BλJ .2 .5 .9 .2 .5 .9γ 0.5 1 0.5 1 0.5 1 0.5 1 0.5 1 0.5 140 0.18% 0.65% 0.89% 0.47% 1.35% 1.05% -0.86% -5.49% -1.16% -0.36% -0.32% -2.04%

0.62% 0.32% 0.87% 0.73% 1.18% 1.43% -0.95% -1.34% -0.81% -0.87% -0.39% -0.25%

42 0.46% 0.43% 1.11% 1.16% 1.10% 1.58% -0.38% -1.17% -0.81% -0.04% 0.26% 0.13%0.71% 0.43% 0.93% 0.89% 1.28% 1.56% -0.77% -1.00% -0.50% -0.56% -0.19% 0.12%

44 0.78% 0.57% 0.94% 0.89% 1.39% 1.74% -0.48% -0.57% -0.08% -0.30% 0.09% 0.57%0.79% 0.61% 1.04% 1.08% 1.34% 1.70% -0.34% -0.52% -0.11% -0.03% 0.20% 0.59%

45 0.78% 0.63% 1.15% 1.28% 1.29% 1.71% -0.08% -0.24% 0.03% 0.33% 0.45% 0.81%0.84% 0.71% 1.04% 1.11% 1.38% 1.78% -0.17% -0.26% 0.12% 0.16% 0.39% 0.86%

46 0.91% 0.79% 1.07% 1.18% 1.47% 1.90% 0.05% 0.02% 0.38% 0.43% 0.62% 1.15%0.87% 0.74% 1.11% 1.21% 1.43% 1.87% 0.07% 0.00% 0.31% 0.44% 0.63% 1.09%

47 0.91% 0.86% 1.06% 1.22% 1.46% 1.94% 0.22% 0.25% 0.56% 0.64% 0.81% 1.36%0.91% 0.83% 1.08% 1.26% 1.47% 1.92% 0.24% 0.24% 0.57% 0.70% 0.81% 1.36%

48 0.90% 0.86% 1.22% 1.43% 1.47% 1.97% 0.60% 0.50% 0.71% 1.08% 1.13% 1.58%0.95% 0.93% 1.18% 1.38% 1.50% 2.02% 0.57% 0.56% 0.75% 1.05% 1.12% 1.64%

49 1.02% 1.06% 1.25% 1.52% 1.59% 2.15% 0.78% 0.83% 1.05% 1.31% 1.33% 1.97%0.98% 0.98% 1.28% 1.52% 1.55% 2.10% 0.80% 0.79% 1.00% 1.29% 1.36% 1.89%

50 1.08% 1.13% 1.31% 1.62% 1.63% 2.25% 1.01% 1.16% 1.32% 1.57% 1.59% 2.27%1.08% 1.16% 1.30% 1.62% 1.64% 2.25% 1.01% 1.14% 1.31% 1.59% 1.57% 2.27%

51 1.10% 1.23% 1.36% 1.69% 1.67% 2.30% 1.30% 1.38% 1.49% 1.87% 1.84% 2.46%1.14% 1.28% 1.34% 1.69% 1.70% 2.38% 1.28% 1.45% 1.54% 1.87% 1.82% 2.56%

52 1.20% 1.33% 1.37% 1.79% 1.75% 2.50% 1.50% 1.70% 1.76% 2.13% 2.03% 2.80%1.15% 1.26% 1.42% 1.82% 1.71% 2.41% 1.55% 1.62% 1.72% 2.16% 2.08% 2.72%

53 1.23% 1.43% 1.50% 1.94% 1.76% 2.53% 1.76% 1.94% 1.96% 2.42% 2.33% 3.02%1.25% 1.45% 1.47% 1.92% 1.78% 2.54% 1.72% 1.95% 1.97% 2.38% 2.29% 3.03%

54 1.20% 1.56% 1.53% 2.05% 1.81% 2.63% 2.00% 2.12% 2.14% 2.72% 2.53% 3.26%1.24% 1.54% 1.54% 2.05% 1.82% 2.66% 1.99% 2.20% 2.15% 2.70% 2.52% 3.28%

55 1.42% 1.70% 1.55% 2.11% 1.94% 2.81% 2.11% 2.47% 2.49% 2.83% 2.69% 3.57%1.34% 1.75% 1.60% 2.18% 1.90% 2.77% 2.16% 2.38% 2.46% 2.91% 2.75% 3.56%

56 1.43% 1.84% 1.70% 2.30% 2.00% 2.95% 2.43% 2.71% 2.62% 3.20% 2.99% 3.81%1.52% 1.82% 1.63% 2.21% 2.05% 2.95% 2.35% 2.74% 2.67% 3.09% 2.89% 3.80%

58 1.64% 2.10% 1.83% 2.58% 2.22% 3.23% 2.80% 3.15% 3.12% 3.66% 3.35% 4.29%1.63% 2.11% 1.96% 2.81% 2.17% 3.22% 2.95% 3.18% 3.10% 3.90% 3.45% 4.30%

60 1.82% 2.42% 2.06% 2.83% 2.40% 3.54% 3.22% 3.62% 3.45% 4.08% 3.78% 4.70%1.68% 2.18% 2.17% 2.92% 2.20% 3.38% 3.32% 3.51% 3.24% 4.09% 3.89% 4.55%

138

Table 16: Commodity Proportional Volatility Jump Table

This table represents the bias in BIV relative to realized term volatility for gas contracts. The futures processis model as either proportional jump-diffusion (Panel A) or proportional jump-diffusion with stochasticvolatility (Panel B). There is no market price of volatility risk in the stochastic volatility case. γ is theintensity of jump arrival and λJ is the market price of jump risk. The starting futures value is equal to $50.All other parameters are fixed and initial values are the same as in prior simulations.

Panel A Panel BλJ .2 .5 .9 .2 .5 .9γ 0.5 1 0.5 1 0.5 1 0.5 1 0.5 1 0.5 1

40 0.92% 1.74% 1.15% 2.51% 1.45% 3.03% 1.57% 0.96% -0.02% 1.44% 2.15% 2.55%1.96% 2.35% 2.18% 2.93% 2.49% 3.47% 0.69% 1.36% 0.96% 1.83% 1.20% 2.50%

42 1.05% 1.24% 1.26% 1.97% 1.57% 2.25% 0.16% 0.13% 0.07% 0.55% 0.75% 1.44%1.20% 1.29% 1.42% 1.74% 1.73% 2.31% -0.10% 0.03% 0.06% 0.44% 0.42% 1.12%

44 1.01% 0.94% 1.24% 1.33% 1.54% 1.96% -0.32% -0.23% 0.07% 0.19% 0.25% 0.76%0.91% 0.87% 1.14% 1.34% 1.43% 1.92% -0.19% -0.23% 0.03% 0.19% 0.36% 0.81%

45 0.89% 0.80% 1.10% 1.37% 1.40% 1.84% 0.05% -0.14% 0.14% 0.30% 0.57% 0.97%0.92% 0.78% 1.13% 1.25% 1.43% 1.81% -0.08% -0.16% 0.18% 0.28% 0.47% 0.87%

46 0.79% 0.63% 1.02% 1.17% 1.32% 1.69% 0.15% -0.19% 0.20% 0.26% 0.67% 0.97%0.82% 0.69% 1.05% 1.24% 1.35% 1.73% 0.08% -0.10% 0.25% 0.36% 0.59% 1.00%

47 0.92% 0.82% 1.15% 1.16% 1.45% 1.84% 0.19% 0.25% 0.59% 0.66% 0.70% 1.16%0.91% 0.83% 1.14% 1.18% 1.44% 1.84% 0.23% 0.23% 0.53% 0.64% 0.75% 1.17%

48 0.90% 0.83% 1.12% 1.26% 1.42% 1.85% 0.45% 0.44% 0.71% 0.88% 1.01% 1.42%0.92% 0.78% 1.14% 1.22% 1.44% 1.81% 0.42% 0.37% 0.71% 0.82% 0.97% 1.38%

49 0.92% 0.84% 1.14% 1.27% 1.45% 1.91% 0.64% 0.64% 0.92% 1.07% 1.18% 1.65%0.90% 0.81% 1.12% 1.27% 1.43% 1.88% 0.67% 0.60% 0.89% 1.03% 1.19% 1.63%

50 1.02% 0.99% 1.25% 1.29% 1.55% 2.00% 0.86% 0.99% 1.24% 1.40% 1.36% 1.83%1.01% 1.02% 1.24% 1.33% 1.54% 2.05% 0.89% 0.99% 1.20% 1.40% 1.41% 1.91%

51 1.02% 1.04% 1.24% 1.49% 1.54% 2.12% 1.20% 1.19% 1.40% 1.65% 1.72% 2.26%1.07% 1.05% 1.29% 1.47% 1.59% 2.12% 1.21% 1.20% 1.43% 1.66% 1.71% 2.26%

52 1.18% 1.26% 1.42% 1.65% 1.73% 2.33% 1.43% 1.61% 1.76% 2.05% 1.96% 2.59%1.14% 1.21% 1.37% 1.63% 1.68% 2.25% 1.45% 1.57% 1.71% 2.01% 1.98% 2.58%

53 1.24% 1.43% 1.45% 1.76% 1.75% 2.43% 1.70% 1.98% 2.01% 2.38% 2.21% 2.88%1.23% 1.47% 1.44% 1.78% 1.74% 2.49% 1.69% 1.99% 1.96% 2.40% 2.22% 2.93%

54 1.26% 1.53% 1.49% 2.08% 1.79% 2.64% 2.09% 2.23% 2.19% 2.71% 2.63% 3.41%1.34% 1.56% 1.57% 2.09% 1.87% 2.65% 2.03% 2.24% 2.24% 2.72% 2.58% 3.38%

55 1.52% 1.96% 1.76% 2.41% 2.06% 2.98% 2.31% 2.76% 2.61% 3.19% 2.85% 3.83%1.44% 1.89% 1.68% 2.35% 1.98% 2.95% 2.34% 2.69% 2.54% 3.13% 2.85% 3.76%

56 1.64% 2.28% 1.86% 2.77% 2.17% 3.32% 2.75% 3.21% 2.85% 3.63% 3.26% 4.31%1.68% 2.28% 1.90% 2.70% 2.21% 3.34% 2.67% 3.18% 2.85% 3.60% 3.20% 4.24%

58 2.34% 3.34% 2.56% 3.73% 2.86% 4.36% 3.34% 4.37% 3.73% 4.79% 3.92% 5.35%2.22% 3.28% 2.45% 3.69% 2.74% 4.35% 3.47% 4.35% 3.69% 4.78% 3.99% 5.34%

60 3.22% 4.68% 3.44% 5.13% 3.74% 5.79% 4.51% 5.66% 4.67% 6.11% 5.04% 6.74%3.29% 4.83% 3.52% 5.30% 3.82% 5.79% 4.28% 5.89% 4.79% 6.34% 4.78% 6.77%

139

Table 17: Commodity Proportional Volatility Jump Model with Market Priceof Volatility Risk

Results of simulation done on given parameter values. Each entry has a result for a call(top) andput(bottom). λσ is the market price of jump risk;ξ is the volatility of the volatility process. κ, θ, µ, σj , λj ,and ξ are given in prior simulations. The starting futures value is $50

ξ 0.3 0.3 0.5 0.5 0.3 0.3 0.5 0.5λσ -2 -0.5 -2 -0.5 -2 -0.5 -2 -0.5

K/S θ = 20% K/S θ = 40%0.8 8.84% 6.45% 10.84% 6.67% 0.8 3.35% 1.34% 3.76% 0.96%

9.06% 8.54% 9.77% 8.64% 3.31% 1.39% 3.82% 0.97%

0.82 8.35% 7.66% 9.44% 7.57% 0.82 3.32% 1.28% 4.02% 0.85%7.29% 6.12% 8.07% 6.42% 3.20% 1.24% 3.68% 0.82%

0.84 5.51% 4.53% 6.29% 3.92% 0.84 3.32% 1.24% 3.77% 0.95%5.17% 4.00% 5.80% 4.10% 3.13% 1.33% 3.87% 1.00%

0.86 3.08% 1.00% 4.48% 1.29% 0.86 3.26% 1.23% 3.79% 0.94%3.12% 2.34% 3.79% 2.45% 3.32% 1.29% 3.92% 1.00%

0.88 1.82% 0.81% 2.07% 0.48% 0.88 3.29% 1.56% 4.19% 1.36%1.93% 0.92% 2.34% 0.89% 3.30% 1.55% 4.17% 1.38%

0.9 1.31% 0.38% 1.71% 0.09% 0.9 3.55% 1.59% 4.37% 1.50%1.15% 0.29% 1.47% 0.03% 3.43% 1.62% 4.40% 1.47%

0.92 0.97% -0.12% 1.28% -0.45% 0.92 3.63% 1.72% 4.53% 1.70%0.89% 0.02% 1.07% -0.33% 3.66% 1.70% 4.57% 1.65%

0.94 0.92% 0.10% 1.09% -0.18% 0.94 3.72% 2.06% 5.03% 2.12%0.98% 0.09% 1.14% -0.25% 3.76% 2.04% 4.99% 2.14%

0.96 1.23% 0.37% 1.49% 0.09% 0.96 3.93% 2.21% 5.27% 2.37%1.16% 0.33% 1.45% 0.03% 3.92% 2.19% 5.22% 2.36%

0.98 1.51% 0.62% 1.91% 0.53% 0.98 4.16% 2.43% 5.50% 2.67%1.50% 0.61% 1.92% 0.50% 4.15% 2.37% 5.43% 2.57%

1 1.84% 1.03% 2.47% 1.16% 1 4.31% 2.67% 5.88% 3.00%1.89% 1.02% 2.52% 1.14% 4.33% 2.70% 5.91% 3.04%

1.02 2.36% 1.45% 3.22% 1.74% 1.02 4.66% 2.82% 6.15% 3.23%2.39% 1.46% 3.27% 1.74% 4.69% 2.82% 6.14% 3.24%

1.04 2.93% 2.03% 3.95% 2.54% 1.04 4.84% 3.12% 6.54% 3.70%2.91% 2.01% 3.94% 2.49% 4.81% 3.05% 6.46% 3.61%

1.06 3.49% 2.64% 4.70% 3.34% 1.06 5.05% 3.37% 6.85% 3.99%3.53% 2.59% 4.72% 3.25% 5.06% 3.41% 6.88% 3.99%

1.08 4.23% 3.23% 5.59% 4.02% 1.08 5.48% 3.53% 7.13% 4.26%4.23% 3.30% 5.54% 4.06% 5.48% 3.54% 7.13% 4.28%

1.1 5.15% 4.19% 6.58% 5.06% 1.1 5.72% 3.82% 7.52% 4.58%5.08% 4.08% 6.49% 4.99% 5.70% 3.81% 7.45% 4.56%

1.12 6.14% 5.11% 7.63% 5.97% 1.12 5.99% 4.09% 7.83% 4.96%6.10% 5.06% 7.53% 6.02% 5.92% 4.11% 7.86% 4.99%

1.14 7.29% 6.24% 8.79% 7.10% 1.14 6.37% 4.35% 8.17% 5.35%7.38% 6.50% 8.64% 7.29% 6.39% 4.39% 8.26% 5.36%

1.16 8.48% 7.69% 9.74% 8.42% 1.16 6.57% 4.83% 8.71% 5.79%8.46% 7.74% 9.84% 8.66% 6.58% 4.84% 8.67% 5.67%

1.18 10.12% 9.14% 11.31% 9.85% 1.18 7.01% 5.07% 9.03% 6.11%9.88% 9.04% 11.10% 9.81% 6.85% 5.05% 9.06% 6.17%

1.2 11.37% 10.44% 12.59% 11.14% 1.2 7.32% 5.49% 9.49% 6.50%11.08% 10.81% 12.05% 11.30% 7.39% 5.52% 9.54% 6.63%

140

Table 18: Mean-Reversion regression of instantaneous volatility and BSIVfrom 30 day options

InstVol is the mean reversion regression run on instantaneous volatility (input to the simulation). BSIV-call/BSIVput is the mean reversion regression done on implied volatility from the call/put. The dependentvariable is change in volatility from t to t− 1. For each case λσ = 0 except for the last where λσ = −2. Theinferred values are backed out from the coefficent estimates.

4σ2 4σ2 4σ2 4σ2

InstVol -0.022 -0.036(5.53)** (6.47)**

BSIVcall -0.022(5.53)**

BSIVput -0.022(5.52)**

Constant 0.000678 0.00072 0.000718 0.000705(4.91)** (5.16)** (5.16)** (5.73)**

Observations 2708 2708 2708 2214R-squared 0.01 0.01 0.01 0.02

Absolute value of t statistics in parentheses* significant at 5%; ** significant at 1%

Inferred Values

λσ = 0 λσ = −2κ 5.61 5.61θ 17.08% 17.75%λσ 0 -1.78

141

Table 19: Equity Mean Reversion Regression

Mean-reversion regression done on the S&P 100 (OEX) and the S&P 500 (SPX). The S&P 100 is split intopre and post October 1987. The dependent variable is change in daily volatility, and is sampled at a dailyfrequency. IV is implied volatility at date t+1.κ is the rate of mean reversion, θ is the level to which variancereverts, and ξ is the variance in the variance process. ξ is found from the standard error in the regression.θ is equal to intercept term divided by the negative of the slope coefficient . κ is recovered by dividing theslope coefficient by −4t. Regression run on the equation shown below.

4σ2 = a + bσ2t

OEX SPXFull Sample Pre Oct-87 Post Oct-87

4σ2 4σ2 4σ2 4σ2

IV -0.201 -0.038 -0.064 -0.058(21.56)** (2.94)** (15.65)** (7.81)**

Constant 0.01 0.002 0.003 0.002(13.16)** (2.89)** (11.81)** (6.58)**

Observations 4182 441 3722 1957R-squared 0.1 0.02 0.06 0.03

Inferred Values

Full OEX Pre 87 Crash Post 87 Crash SPXκ 50.8543 9.4528 16.1151 14.6749θ 0.0514 0.0468 0.0475 0.0381√θ 22.66% 21.64% 21.79% 19.52%ξ 1.546 0.2465 0.4948 0.521

Absolute value of t statistics in parentheses* significant at 5%; ** significant at 1%

142

Tab

le20

:C

omm

odity

Mea

nR

ever

sion

Reg

ress

ion

Mea

n-r

ever

sion

regre

ssio

ndone

on

each

month

gas

contr

act

.T

he

dep

enden

tvari

able

isch

ange

invola

tility

,and

issa

mple

dat

adaily

freq

uen

cy.κ

isth

era

teofm

ean

rever

sion,

θis

the

level

tow

hic

hvari

ance

rever

ts,and

ξis

the

vari

ance

inth

evari

ance

pro

cess

isfo

und

from

the

standard

erro

rin

the

regre

ssio

n.

θis

equalto

firs

tsl

ope

coeffi

cien

tdiv

ided

by

the

neg

ati

ve

of

the

seco

nd

slope

coeffi

cien

t.

κis

reco

ver

edby

div

idin

gth

esl

ope

coeffi

cien

tby−4

t.R

egre

ssio

nru

non

equation

25

inth

epaper

as

show

nbel

ow

.

2=

b 0+

b 11 t2

+b 2

σ2 t

Model1

Model2

Month

1 t2

σ2 t

Const

ant

R2

DW

1 t2

σ2 t

Const

ant

R2

DW

Jan

0.1

89

(14.2

4)

-6.6

66

(2.3

5)

-1.6

46

-(3.8

1)

0.1

51.3

20.1

95

(12.4

1)

-3.8

99

(0.8

5)

-1.3

10

-(2.1

6)

0.1

51.3

2

Feb

0.2

80

(9.8

1)

-5.9

13

(1.2

7)

-1.9

18

-(2.4

6)

0.0

81.7

90.3

05

(9.3

8)

-0.8

01

-(0.1

3)

-1.1

30

-(1.2

1)

0.0

81.7

8

Mar

0.2

15

(7.5

6)

-21.3

51

-(4.4

3)

2.3

69

(3)

0.0

31.8

80.2

54

(8.2

3)

-33.3

30

-(5.5

6)

3.7

75

(4.2

3)

0.0

31.8

7

Apr

0.2

04

(9.3

1)

-20.8

76

-(3.2

8)

1.0

75

(1.3

8)

0.0

51.6

20.2

33

(9.7

6)

-39.2

95

-(4.3

4)

2.9

25

(2.8

8)

0.0

51.6

1

May

0.1

21

(8.0

9)

-22.4

86

-(3.8

6)

1.5

15

(2.5

7)

0.0

42.1

50.1

55

(9.4

9)

-58.7

40

-(6.4

2)

4.6

23

(5.4

9)

0.0

52.1

1

Jun

0.0

69

(4.8

3)

-18.1

89

-(4.0

8)

1.5

06

(3.4

7)

0.0

12.2

40.1

06

(6.9

)-5

5.6

32

-(7.7

7)

4.4

64

(7.2

)0.0

32.2

0

Jul

0.0

91

(8.1

)-8

.199

-(2.0

7)

0.4

80

(1.0

8)

0.0

41.8

90.1

19

(8.9

8)

-36.9

85

-(4.4

7)

3.2

18

(3.9

1)

0.0

41.8

6

Aug

0.1

17

(10.2

9)

-4.5

34

-(1.1

5)

-0.1

61

-(0.3

6)

0.0

72.1

20.1

36

(9.9

5)

-19.7

17

-(2.5

6)

1.2

66

(1.6

2)

0.0

72.1

0

Sep

0.1

42

(11.1

9)

-5.8

11

-(1.4

8)

0.0

80

(0.1

7)

0.0

71.5

50.1

84

(11.9

7)

-31.7

06

-(4.7

5)

2.5

97

(3.7

)0.0

81.5

3

Oct

0.1

82

(14.3

5)

-11.1

54

-(3.1

5)

0.3

66

(0.8

2)

0.1

21.8

20.2

27

(14.5

3)

-35.2

27

-(5.7

7)

2.8

54

(4.1

8)

0.1

21.8

1

Nov

0.1

62

(13.2

5)

-1.8

98

-(0.6

)-0

.454

-(1.0

6)

0.1

21.8

10.1

80

(12.1

1)

-10.5

65

-(2.0

3)

0.5

12

(0.8

2)

0.1

21.8

1

Dec

0.1

70

(14.0

8)

-3.5

76

-(1.2

7)

-0.0

50

-(0.1

3)

0.1

11.8

10.1

89

(13.1

8)

-11.7

65

-(2.7

5)

0.9

17

(1.6

7)

0.1

11.8

1

Infe

rred

Valu

es

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

κ0.9

83

0.2

02

8.3

99

9.9

02

14.8

02

14.0

19

9.3

20

4.9

69

7.9

90

8.8

77

2.6

62

2.9

65

θ0.2

86

0.3

81

0.1

21

0.0

80

0.0

81

0.0

82

0.0

90

0.0

71

0.0

88

0.0

87

0.0

65

0.0

94

√θ

53.5

%61.7

%34.8

%28.3

%28.5

%28.7

%30.0

%26.7

%29.6

%29.6

%25.6

%30.6

%

ξ0.2

97

0.5

26

0.9

83

0.9

27

0.6

45

0.6

24

0.4

56

0.5

08

0.5

15

0.4

85

0.5

38

0.4

47

Abso

lute

valu

eoft

statist

ics

inpare

nth

eses

*si

gnifi

cant

at

5%

;**

signifi

cant

at

1%

Model

2is

afixed

effec

tsre

gre

ssio

nco

ntr

ollin

gfo

ryea

rIn

ferr

edvalu

esco

me

from

Model

2

143

Table 21: Black Implied Volatility

The implied volatility is found by inverting the Black model for each call and put contract separately. Theimplied volatilities are then averaged across each moneyness/maturity combination defined by the strike tospot ratio (K/S) and the days until maturity. The sub periods are broken up into seasons, where winter isthe monthly contracts for December, January, and February and the other seasons follow as such.

Call PutDays to Maturity Days to Maturity

Sample K/S ≥180 60-180 ≤60 ≥180 60-180 ≤60

Full ≤.8 52.58% 78.07% 158.72% 51.56% 106.79% 117.14%.8-.95 46.67% 68.36% 147.31% 50.61% 68.36% 150.77%.95-1.05 48.13% 66.07% 164.84% 47.64% 61.25% 161.35%1.05-1.2 53.03% 75.71% 154.41% 49.11% 59.95% 123.33%≥1.2 62.87% 93.79% 147.17% 52.21% 70.09% 130.51%

Winter ≤.8 58.71% 77.19% 118.50% 50.65% - 118.29%.8-.95 52.17% 68.35% 122.14% 53.45% 65.67% 132.56%.95-1.05 54.60% 66.28% 130.69% 52.98% 62.85% 137.99%1.05-1.2 57.52% 75.38% 151.25% 53.41% 65.28% 124.50%≥1.2 63.01% 91.49% 232.50% 56.36% 74.74% 127.04%

Spring ≤.8 46.74% 59.48% 71.25% - 106.85% 113.48%.8-.95 43.68% 56.49% 83.13% 48.67% 70.15% 90.27%.95-1.05 44.67% 58.42% 109.56% 45.15% 57.95% 71.58%1.05-1.2 49.35% 59.58% 101.43% 47.98% 56.87% 62.73%≥1.2 55.82% 76.15% - 51.75% 62.26% 61.47%

Summer ≤.8 42.84% 58.17% 214.64% - - -.8-.95 40.98% 55.62% 179.18% 44.48% 48.67% 229.39%.95-1.05 42.65% 57.16% 184.63% 42.56% 49.91% 185.59%1.05-1.2 44.90% 64.12% 167.74% 45.62% 48.27% 101.70%≥1.2 63.85% 85.29% 167.56% 48.56% 49.90% 86.06%

Fall ≤.8 50.29% 130.93% 253.30% 54.44% - -.8-.95 45.80% 93.37% 236.47% 47.81% 77.54% 175.87%.95-1.05 48.67% 80.76% 215.23% 47.68% 69.57% 193.57%1.05-1.2 51.66% 87.34% 158.17% 46.40% 61.86% 215.92%≥1.2 65.83% 97.07% 125.26% 48.85% 80.90% 189.07%

144

Table 22: Black Implied Volatility Cont..

The implied volatility is found by inverting the Black model for each call and put contract separately. Theimplied volatilities are then averaged across each moneyness/maturity combination defined by the strike tospot ratio (K/S) and the days until maturity. The sub periods are the yearly expirations, where the 2000year are all the option contracts that have a 2000 expiration date.

Call PutDays to Maturity Days to Maturity

Sample K/S ≥180 60-180 ≤60 ≥180 60-180 ≤60

2000 ≤.8 58.56% 146.93% 229.26% - - -.8-.95 42.15% 94.74% 213.98% - - -.95-1.05 56.84% 98.77% 215.31% 38.85% 54.00% -1.05-1.2 65.86% 105.82% 169.80% 32.69% 47.96% 58.28%≥1.2 77.42% 104.94% 144.26% 37.78% 48.16% 59.01%

2001 ≤.8 54.60% 61.27% 90.18% 50.25% 106.85% 117.24%.8-.95 48.27% 58.37% 88.63% 49.53% 65.40% 144.55%.95-1.05 48.84% 58.71% 97.02% 47.63% 58.60% 156.53%1.05-1.2 53.58% 64.36% 99.97% 47.75% 63.35% 137.83%≥1.2 65.88% 77.80% 90.00% 45.75% 85.31% 165.34%

2002 ≤.8 49.20% 51.14% 71.20% 53.75% - -.8-.95 48.95% 50.05% 70.27% 53.39% 74.64% 169.19%.95-1.05 49.69% 55.86% 86.67% 50.43% 68.73% 169.96%1.05-1.2 53.39% 60.88% 83.33% 50.63% 60.77% 98.20%≥1.2 59.61% 94.00% 385.00% 52.65% 62.85% 80.54%

2003 ≤.8 47.34% 48.64% - - - -.8-.95 45.01% 49.15% - 49.29% 50.33% -.95-1.05 44.16% 50.20% - 44.23% 50.12% -1.05-1.2 48.91% 51.21% - 45.97% 51.05% -≥1.2 57.88% - - 50.00% 51.39% -

145

Table 23: Out of Sample Pricing Errors- 1 Day Ahead

For each model the option price was calculated using the previous day’s structural parameter estimates andimplied volatility. The dollar pricing error is the sample average of the absolute difference between the optionmodel implied price and the actual price. The sample period is from January 2000-October 2003, with atotal of 40,563 call option prices and 48,928 put option prices. The models used are as followed: (1) Blackoption models (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochasticvolatility with independent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps andterm structure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps(DPS).

Call Options Put OptionsDays to expiration Days to expiration

K/S model ≥180 60-180 ≤60 ≥180 60-180 ≤60

≤.8 B $0.04 $0.08 $0.16 $0.02 $0.04 $0.06SV $0.02 $0.04 $0.09 $0.01 $0.04 $0.04SVJ $0.01 $0.02 $0.03 $0.01 $0.04 $0.04

SVJT $0.01 $0.02 $0.03 $0.01 $0.02 $0.04SVDJ $0.01 $0.02 $0.03 $0.01 $0.02 $0.04DPS $0.01 $0.02 $0.02 $0.01 $0.04 $0.04

.8-.95 B $0.00 $0.06 $0.08 $0.02 $0.03 $0.15SV $0.00 $0.03 $0.04 $0.01 $0.02 $0.03SVJ $0.00 $0.02 $0.02 $0.01 $0.02 $0.04

SVJT $0.00 $0.02 $0.02 $0.01 $0.02 $0.03SVDJ $0.00 $0.02 $0.02 $0.01 $0.02 $0.03DPS $0.00 $0.02 $0.02 $0.01 $0.02 $0.04

.95-1.05 B $0.01 $0.04 $0.04 $0.02 $0.03 $0.09SV $0.01 $0.03 $0.03 $0.02 $0.03 $0.03SVJ $0.01 $0.03 $0.02 $0.01 $0.03 $0.03

SVJT $0.01 $0.02 $0.03 $0.01 $0.02 $0.03SVDJ $0.01 $0.02 $0.03 $0.01 $0.02 $0.03DPS $0.01 $0.02 $0.02 $0.01 $0.02 $0.03

1.05-1.2 B $0.03 $0.06 $0.13 $0.05 $0.05 $0.05SV $0.03 $0.06 $0.07 $0.05 $0.05 $0.03SVJ $0.02 $0.04 $0.04 $0.03 $0.03 $0.03

SVJT $0.01 $0.02 $0.03 $0.01 $0.02 $0.02SVDJ $0.01 $0.02 $0.03 $0.01 $0.02 $0.02DPS $0.01 $0.04 $0.03 $0.01 $0.03 $0.03

≥1.2 B $0.06 $0.10 $0.24 $0.03 $0.04 $0.09SV $0.03 $0.08 $0.07 $0.03 $0.03 $0.04SVJ $0.02 $0.07 $0.09 $0.02 $0.02 $0.04

SVJT $0.02 $0.04 $0.04 $0.01 $0.02 $0.03SVDJ $0.02 $0.03 $0.03 $0.01 $0.02 $0.03DPS $0.01 $0.07 $0.12 $0.01 $0.02 $0.04

146

Table 24: Out of Sample Pricing Errors- 5 Day Ahead

For each model the option price was calculated using the previous 5 days structural parameter estimatesand implied volatility. The dollar pricing error is the sample average of the absolute difference between theoption model implied price and the actual price. The sample period is from January 2000-October 2003, witha total of 40,563 call option prices and 48,928 put option prices. The models used are as followed: (1) Blackoption models (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochasticvolatility with independent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps andterm structure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps(DPS).

Call Options Put OptionsDays to expiration Days to expiration

K/S model ≥180 60-180 ≤60 ≥180 60-180 ≤60

≤.8 B $0.03 $0.07 $0.15 $0.01 $0.11 $0.12SV $0.02 $0.06 $0.10 $0.01 $0.11 $0.12SVJ $0.02 $0.04 $0.06 $0.01 $0.10 $0.12

SVJT $0.01 $0.02 $0.03 $0.01 $0.05 $0.08SVDJ $0.01 $0.02 $0.03 $0.01 $0.05 $0.08DPS $0.01 $0.03 $0.03 $0.01 $0.11 $0.11

.8-.95 B $0.00 $0.07 $0.10 $0.02 $0.04 $0.11SV $0.00 $0.06 $0.07 $0.02 $0.05 $0.10SVJ $0.00 $0.05 $0.05 $0.02 $0.05 $0.10

SVJT $0.00 $0.03 $0.03 $0.02 $0.03 $0.05SVDJ $0.00 $0.03 $0.03 $0.02 $0.03 $0.04DPS $0.00 $0.04 $0.04 $0.01 $0.05 $0.06

.95-1.05 B $0.02 $0.06 $0.07 $0.03 $0.04 $0.08SV $0.02 $0.05 $0.07 $0.03 $0.05 $0.07SVJ $0.02 $0.04 $0.06 $0.02 $0.04 $0.08

SVJT $0.02 $0.03 $0.04 $0.02 $0.03 $0.04SVDJ $0.02 $0.03 $0.04 $0.02 $0.03 $0.04DPS $0.02 $0.04 $0.05 $0.02 $0.04 $0.03

1.05-1.2 B $0.03 $0.07 $0.11 $0.05 $0.06 $0.06SV $0.03 $0.07 $0.11 $0.05 $0.07 $0.07SVJ $0.02 $0.07 $0.14 $0.03 $0.05 $0.08

SVJT $0.02 $0.03 $0.05 $0.02 $0.03 $0.04SVDJ $0.02 $0.03 $0.05 $0.02 $0.03 $0.03DPS $0.02 $0.06 $0.05 $0.02 $0.04 $0.03

≥1.2 B $0.06 $0.12 $0.15 $0.04 $0.05 $0.13SV $0.03 $0.12 $0.16 $0.04 $0.04 $0.09SVJ $0.03 $0.11 $0.09 $0.03 $0.04 $0.09

SVJT $0.02 $0.04 $0.03 $0.02 $0.02 $0.03SVDJ $0.02 $0.04 $0.05 $0.01 $0.02 $0.03DPS $0.02 $0.04 $0.05 $0.02 $0.04 $0.03

147

Table 25: Percentage Pricing Errors

For each model the option price was calculated using the same day parameter estimates and implied volatility.The percentage pricing error is the sample average of the difference between the option model implied priceand the actual price, divided by the actual price. The sample period is from January 2000-October 2003, witha total of 40,563 call option prices and 48,928 put option prices. The models used are as followed: (1) Blackoption models (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochasticvolatility with independent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps andterm structure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps(DPS).

Call Options Put OptionsDays to expiration Days to expiration

K/S model ≥180 60-180 ≤60 ≥180 60-180 ≤60

≤.8 B 0.63% -4.00% -9.23% -7.06% -4.40% -3.09%SV -0.32% -1.32% -4.07% -0.82% -3.58% 0.48%SVJ -0.10% -0.21% -0.16% 0.19% -3.22% 0.08%

SVJT -0.08% -0.22% -0.43% 0.26% -3.30% 0.08%SVDJ -0.09% -0.06% -0.23% -0.10% -3.18% 0.62%DPS 0.05% 0.21% 0.83% -0.71% -3.31% -0.21%

.8-.95 B 1.44% -1.22% -4.29% -4.42% -3.79% -29.87%SV -0.24% -0.68% -1.54% -1.38% 0.71% 0.11%SVJ -0.06% 0.30% 0.41% -0.98% 0.41% 0.38%

SVJT -0.04% -0.14% -0.15% -0.36% 0.04% 0.32%SVDJ -0.04% 0.23% 0.28% -0.35% 0.03% 0.22%DPS 0.12% 0.62% 0.21% -0.47% 0.97% 0.36%

.95-1.05 B 0.16% -1.20% 1.37% -3.07% -4.24% -16.84%SV -0.36% -0.80% 0.72% -1.93% -2.69% -0.53%SVJ -0.14% -0.10% -0.43% -1.01% -2.03% -0.57%

SVJT 0.13% -0.03% 0.88% -0.12% -0.31% -0.58%SVDJ 0.11% 0.00% -0.14% -0.07% -0.40% -0.58%DPS 0.05% 0.47% -0.98% -0.07% -0.49% -0.49%

1.05-1.2 B -4.11% -6.37% 29.45% -3.87% -6.15% -4.88%SV -2.98% -6.87% 10.40% -4.20% -6.04% -0.22%SVJ -1.75% -4.97% 0.74% -2.36% -2.97% -0.16%

SVJT -0.30% -0.42% 4.03% 0.09% -0.39% -0.15%SVDJ -0.23% -0.59% 2.04% 0.07% -0.43% -0.12%DPS -0.46% -3.43% -1.29% -0.12% -1.61% -0.21%

≥1.2 B -12.06% -3.04% 74.44% -0.45% -0.07% 2.46%SV -3.74% -13.19% 19.07% -1.57% -0.97% -0.51%SVJ -1.39% -7.27% 7.84% -1.03% -0.37% -0.23%

SVJT -0.79% -0.52% 11.00% -0.20% -0.10% -0.23%SVDJ -0.59% -0.64% 6.88% -0.21% -0.08% -0.26%DPS -0.32% -8.76% 0.64% -0.38% -0.34% -0.57%

148

Table 26: In Sample Parameter Estimation and Fit of Gas Price Process

The table below displays the structural parameters and goodness-of-fit for the following option models:(1) Black option models (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ),(4) stochastic volatility with independent return and volatility jumps (SVDJ), (5) stochastic volatility withjumps and term structure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and returnjumps (DPS). The structural parameters are estimated minimizing the sum of squared difference betweenthe market price and the model estimated price. The RMSE denoted the sum of square root of the sumof squares errors for all options estimated. The structural parameters, κ, θ, and ξ, are the stochasticvolatility components representing the speed of mean reversion, the square root of the long run mean, andthe variation of the volatility V (t). The parameters λ, µ, and σj , represent the frequency of jumps peryear, the mean jump size, and the standard deviation of the jump. The parameters α and β are TSOVparameters, λy and µy are volatility jump parameters, and do and δ capture correlated return-volatilityjump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPS

κ 1.779 2.802 2.534 2.027 2.441(0.029) (0.106) (0.077) (0.026) (0.071)

θ 0.341 0.294 0.213 0.288 0.291(0.022) (0.010) (0.022) (0.010) (0.016)

ξ 9.951 3.449 3.471 2.649 2.031(0.489) (0.264) (0.272) (0.234) (0.146)

ρ 0.149 0.147 0.147 0.149 0.219(0.016) (0.013) (0.013) (0.011) (0.014)

λ 1.299 1.352 1.377 1.115(0.035) (0.058) (0.053) (0.058)

µ 0.243 0.234 0.130 0.152(0.061) (0.047) (0.041) (0.042)

σj 1.580 1.520 0.847 0.834(0.113) (0.117) (0.078) (0.057)

λy/α/do 0.918 1.391 -0.694(0.024) (0.061) (0.062)

µy/β/δ -0.255 0.021 -0.093(0.055) (0.011) (0.039)

Implied Volatility 75.19% 111.20% 59.00% 56.76% 56.23% 50.77%(0.013) (0.028) (0.013) (0.013) (0.011) (0.020)

RMSE 392.21 194.65 161.78 161.06 153.84 158.32

NOB 2356 2356 2356 2356 2356 2356

149

Table 27: Parameter Estimation for BIV less than 50%

The table below displays the structural parameters and goodness-of-fit for the following option models forBlack implied volatility of less than 50%: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.935 1.946 1.945 1.945 1.921

(0.011) (0.004) (0.003) (0.002) (0.007)

θ 0.304 0.318 0.307 0.315 0.269(0.005) (0.005) (0.004) (0.005) (0.004)

ξ 0.825 0.389 0.419 0.375 0.453(0.162) (0.015) (0.021) (0.014) (0.013)

ρ 0.376 0.256 0.249 0.270 0.329(0.023) (0.015) (0.015) (0.013) (0.017)

λ 1.106 1.108 1.063 0.970(0.033) (0.028) (0.018) (0.008)

µ 0.059 0.064 0.063 -0.036(0.010) (0.010) (0.010) (0.013)

σj 0.045 0.044 0.041 0.035(0.004) (0.004) (0.003) (0.002)

λy/α/do 1.004 1.007 -0.010(0.001) (0.004) (0.016)

µy/β/δ 0.017 0.009 0.002(0.004) (0.004) (0.009)

Implied Volatility 44.11% 48.45% 43.34% 42.43% 43.17% 39.50%(0.002) (0.007) (0.004) (0.004) (0.004) (0.003)

RMSE 7.92 4.65 4.35 4.35 4.32 4.41

NOB 716 716 716 716 716 716

150

Table 28: Parameter Estimation for BIV less than 80%

The table below displays the structural parameters and goodness-of-fit for the following option models forBlack implied volatility of less than 80%: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.865 2.591 2.319 2.019 2.265

(0.018) (0.113) (0.072) (0.028) (0.059)

θ 0.311 0.316 0.256 0.304 0.244(0.010) (0.007) (0.015) (0.005) (0.005)

ξ 2.306 0.989 0.841 0.442 0.723(0.212) (0.112) (0.087) (0.021) (0.037)

ρ 0.234 0.186 0.186 0.189 0.200(0.017) (0.013) (0.013) (0.011) (0.015)

λ 1.121 1.127 1.113 0.947(0.016) (0.016) (0.011) (0.010)

µ 0.169 0.161 0.072 -0.041(0.028) (0.026) (0.010) (0.011)

σj 0.541 0.441 0.172 0.330(0.072) (0.064) (0.030) (0.043)

λy/α/do 0.939 1.113 -0.267(0.025) (0.030) (0.033)

µy/β/δ -0.200 0.009 0.049(0.057) (0.005) (0.026)

Implied Volatility 53.61% 65.00% 54.04% 52.43% 51.08% 46.73%(0.002) (0.010) (0.010) (0.009) (0.005) (0.007)

RMSE 157.11 120.06 107.68 108.02 104.50 107.77

NOB 1877 1877 1877 1877 1877 1877

151

Table 29: Parameter Estimation for BIV less than 100%

The table below displays the structural parameters and goodness-of-fit for the following option models forBlack implied volatility of less than 100%: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.835 2.782 2.510 2.025 2.374

(0.019) (0.117) (0.084) (0.026) (0.062)

θ 0.305 0.303 0.230 0.295 0.242(0.010) (0.006) (0.023) (0.005) (0.005)

ξ 2.798 1.153 1.011 0.488 0.929(0.217) (0.117) (0.095) (0.023) (0.052)

ρ 0.192 0.177 0.173 0.164 0.193(0.017) (0.013) (0.013) (0.011) (0.015)

λ 1.139 1.134 1.144 0.943(0.018) (0.015) (0.015) (0.009)

µ 0.172 0.171 0.081 0.013(0.027) (0.026) (0.012) (0.041)

σj 0.768 0.654 0.221 0.403(0.080) (0.071) (0.029) (0.045)

λy/α/do 0.908 1.151 -0.347(0.027) (0.031) (0.037)

µy/β/δ -0.257 0.006 0.041(0.062) (0.004) (0.034)

Implied Volatility 56.15% 70.54% 54.39% 53.07% 51.70% 47.96%(0.003) (0.011) (0.010) (0.009) (0.006) (0.007)

RMSE 222.69 168.18 146.67 147.17 142.15 146.83

NOB 2029 2029 2029 2029 2029 2029

152

Table 30: Parameter Estimation for BIV less than 150%

The table below displays the structural parameters and goodness-of-fit for the following option models forBlack implied volatility of less than 150%: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.818 2.858 2.572 2.029 2.387

(0.024) (0.116) (0.084) (0.027) (0.059)

θ 0.313 0.309 0.220 0.296 0.256(0.012) (0.009) (0.022) (0.009) (0.005)

ξ 4.291 1.366 1.190 0.650 1.010(0.270) (0.127) (0.107) (0.042) (0.052)

ρ 0.169 0.167 0.162 0.157 0.216(0.017) (0.013) (0.013) (0.011) (0.014)

λ 1.157 1.148 1.179 0.943(0.018) (0.017) (0.018) (0.009)

µ 0.171 0.168 0.092 0.075(0.026) (0.025) (0.014) (0.040)

σj 0.971 0.841 0.328 0.468(0.084) (0.073) (0.030) (0.043)

λy/α/do 0.914 1.184 -0.478(0.026) (0.033) (0.041)

µy/β/δ -0.244 0.006 -0.011(0.059) (0.007) (0.033)

Implied Volatility 59.92% 81.61% 54.04% 52.42% 51.27% 47.81%(0.004) (0.016) (0.010) (0.009) (0.006) (0.006)

RMSE 270.53 179.70 155.09 155.44 149.89 154.60

NOB 2153 2153 2153 2153 2153 2153

153

Table 31: Parameter Estimation for BIV less than 200%

The table below displays the structural parameters and goodness-of-fit for the following option models forBlack implied volatility of less than 200%: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.801 2.834 2.558 2.023 2.392

(0.030) (0.111) (0.081) (0.026) (0.057)

θ 0.321 0.304 0.224 0.296 0.270(0.012) (0.010) (0.023) (0.010) (0.006)

ξ 6.684 1.708 1.608 1.014 1.225(0.381) (0.143) (0.132) (0.091) (0.069)

ρ 0.149 0.150 0.149 0.147 0.222(0.016) (0.013) (0.013) (0.011) (0.014)

λ 1.213 1.266 1.286 0.965(0.032) (0.058) (0.053) (0.010)

µ 0.207 0.203 0.111 0.115(0.030) (0.028) (0.016) (0.039)

σj 1.206 1.091 0.511 0.600(0.095) (0.087) (0.053) (0.047)

λy/α/do 0.915 1.232 -0.647(0.025) (0.034) (0.047)

µy/β/δ -0.248 0.017 -0.056(0.058) (0.010) (0.033)

Implied Volatility 64.29% 96.25% 54.06% 52.86% 51.66% 47.70%(0.006) (0.024) (0.011) (0.011) (0.008) (0.006)

RMSE 315.23 184.85 157.32 157.55 150.69 155.72

NOB 2240 2240 2240 2240 2240 2240

154

Table 32: Parameter Estimation for BIV less than 300%

The table below displays the structural parameters and goodness-of-fit for the following option models forBlack implied volatility of less than 300%: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.782 2.805 2.542 2.014 2.387

(0.029) (0.108) (0.078) (0.026) (0.056)

θ 0.318 0.296 0.218 0.293 0.272(0.012) (0.010) (0.023) (0.010) (0.006)

ξ 8.698 2.300 2.243 1.520 1.518(0.456) (0.183) (0.179) (0.139) (0.091)

ρ 0.143 0.141 0.140 0.143 0.221(0.016) (0.013) (0.013) (0.011) (0.014)

λ 1.264 1.314 1.340 1.011(0.033) (0.058) (0.052) (0.014)

µ 0.226 0.242 0.134 0.147(0.030) (0.030) (0.017) (0.039)

σj 1.493 1.445 0.745 0.760(0.111) (0.116) (0.072) (0.054)

λy/α/do 0.916 1.353 -0.749(0.024) (0.055) (0.051)

µy/β/δ -0.246 0.016 -0.094(0.056) (0.010) (0.034)

Implied Volatility 69.31% 105.79% 54.70% 53.19% 52.27% 47.75%(0.009) (0.027) (0.011) (0.011) (0.009) (0.006)

RMSE 359.97 191.78 160.39 160.61 152.57 157.66

NOB 2302 2302 2302 2302 2302 2302

155

Table 33: Parameter Estimation for All options in 2000

The table below displays the structural parameters and goodness-of-fit for the following option models foryear 2000: (1) Black option models (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps(SVJ), (4) stochastic volatility with independent return and volatility jumps (SVDJ), (5) stochastic volatilitywith jumps and term structure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility andreturn jumps (DPS). The structural parameters are estimated minimizing the sum of squared differencebetween the market price and the model estimated price. The RMSE denoted the sum of square root of thesum of squares errors for all options estimated. The structural parameters, κ, θ, and ξ, are the stochasticvolatility components representing the speed of mean reversion, the square root of the long run mean, andthe variation of the volatility V (t). The parameters λ, µ, and σj , represent the frequency of jumps peryear, the mean jump size, and the standard deviation of the jump. The parameters α and β are TSOVparameters, λy and µy are volatility jump parameters, and do and δ capture correlated return-volatilityjump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 0.292 6.132 5.024 2.014 3.745

(0.106) (0.669) (0.498) (0.157) (0.298)

θ 0.376 -0.023 -0.541 0.014 0.414(0.083) (0.053) (0.176) (0.058) (0.050)

ξ 58.345 12.481 12.374 9.732 9.901(2.706) (1.670) (1.788) (1.681) (1.105)

ρ -0.939 -0.267 -0.295 -0.349 0.576(0.008) (0.066) (0.064) (0.035) (0.056)

λ 2.847 3.724 3.822 2.185(0.380) (0.745) (0.656) (0.168)

µ -0.359 -0.477 -0.345 1.925(0.128) (0.010) (0.087) (0.162)

σj 11.457 11.617 6.391 4.370(0.932) (1.086) (0.831) (0.413)

λy/α/do 0.616 4.597 -6.068(0.164) (0.716) (0.253)

µy/β/δ -0.733 -0.135 -2.197(0.387) (0.080) (0.213)

Implied Volatility 153.29% 472.57% 23.48% 29.48% 30.59% 30.65%(0.057) (0.153) (0.061) (0.084) (0.083) (0.026)

RMSE 129.31 57.18 41.65 41.43 37.48 39.25

NOB 170 170 170 170 170 170

156

Table 34: Parameter Estimation for All options in 2001

The table below displays the structural parameters and goodness-of-fit for the following option models foryear 2001: (1) Black option models (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps(SVJ), (4) stochastic volatility with independent return and volatility jumps (SVDJ), (5) stochastic volatilitywith jumps and term structure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility andreturn jumps (DPS). The structural parameters are estimated minimizing the sum of squared differencebetween the market price and the model estimated price. The RMSE denoted the sum of square root of thesum of squares errors for all options estimated. The structural parameters, κ, θ, and ξ, are the stochasticvolatility components representing the speed of mean reversion, the square root of the long run mean, andthe variation of the volatility V (t). The parameters λ, µ, and σj , represent the frequency of jumps peryear, the mean jump size, and the standard deviation of the jump. The parameters α and β are TSOVparameters, λy and µy are volatility jump parameters, and do and δ capture correlated return-volatilityjump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.851 3.072 2.693 2.089 2.562

(0.054) (0.187) (0.134) (0.048) (0.101)

θ 0.351 0.295 0.225 0.292 0.239(0.042) (0.016) (0.036) (0.018) (0.009)

ξ 10.602 4.720 4.733 3.637 2.159(0.646) (0.456) (0.464) (0.393) (0.208)

ρ 0.309 0.183 0.184 0.200 0.245(0.021) (0.019) (0.019) (0.016) (0.020)

λ 1.199 1.194 1.241 0.896(0.033) (0.032) (0.033) (0.018)

µ 0.620 0.603 0.518 0.096(0.114) (0.085) (0.080) (0.071)

σj 1.323 1.158 0.667 0.919(0.120) (0.102) (0.063) (0.075)

λy/α/do 0.878 1.253 -0.546(0.042) (0.054) (0.066)

µy/β/δ -0.419 0.053 0.127(0.095) (0.017) (0.054)

Implied Volatility 81.46% 102.70% 59.88% 56.12% 57.63% 48.44%(0.021) (0.028) (0.020) (0.018) (0.018) (0.008)

RMSE 251.07 129.46 113.49 113.96 110.13 112.90

NOB 1156 1156 1156 1156 1156 1156

157

Table 35: Parameter Estimation for All options in 2002

The table below displays the structural parameters and goodness-of-fit for the following option models foryear 2002: (1) Black option models (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps(SVJ), (4) stochastic volatility with independent return and volatility jumps (SVDJ), (5) stochastic volatilitywith jumps and term structure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility andreturn jumps (DPS). The structural parameters are estimated minimizing the sum of squared differencebetween the market price and the model estimated price. The RMSE denoted the sum of square root of thesum of squares errors for all options estimated. The structural parameters, κ, θ, and ξ, are the stochasticvolatility components representing the speed of mean reversion, the square root of the long run mean, andthe variation of the volatility V (t). The parameters λ, µ, and σj , represent the frequency of jumps peryear, the mean jump size, and the standard deviation of the jump. The parameters α and β are TSOVparameters, λy and µy are volatility jump parameters, and do and δ capture correlated return-volatilityjump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.938 1.939 1.935 1.953 1.946

(0.014) (0.005) (0.005) (0.005) (0.007)

θ 0.324 0.358 0.328 0.333 0.294(0.006) (0.013) (0.007) (0.005) (0.004)

ξ 1.355 0.575 0.651 0.351 0.403(0.335) (0.068) (0.098) (0.033) (0.021)

ρ -0.004 0.144 0.149 0.131 0.013(0.029) (0.021) (0.021) (0.019) (0.022)

λ 1.193 1.174 1.151 1.018(0.031) (0.021) (0.030) (0.020)

µ 0.216 0.208 0.008 -0.082(0.066) (0.062) (0.023) (0.014)

σj 0.302 0.320 0.162 0.137(0.115) (0.120) (0.067) (0.049)

λy/α/do 1.011 1.016 -0.190(0.002) (0.010) (0.046)

µy/β/δ 0.009 0.006 -0.020(0.023) (0.009) (0.017)

Implied Volatility 59.43% 65.56% 70.97% 68.59% 64.43% 56.40%(0.004) (0.013) (0.023) (0.021) (0.009) (0.015)

RMSE 9.94 7.33 6.04 6.06 5.71 6.06

NOB 770 770 770 770 770 770

158

Table 36: Parameter Estimation for All options in 2003

The table below displays the structural parameters and goodness-of-fit for the following option models foryear 2003: (1) Black option models (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps(SVJ), (4) stochastic volatility with independent return and volatility jumps (SVDJ), (5) stochastic volatilitywith jumps and term structure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility andreturn jumps (DPS). The structural parameters are estimated minimizing the sum of squared differencebetween the market price and the model estimated price. The RMSE denoted the sum of square root of thesum of squares errors for all options estimated. The structural parameters, κ, θ, and ξ, are the stochasticvolatility components representing the speed of mean reversion, the square root of the long run mean, andthe variation of the volatility V (t). The parameters λ, µ, and σj , represent the frequency of jumps peryear, the mean jump size, and the standard deviation of the jump. The parameters α and β are TSOVparameters, λy and µy are volatility jump parameters, and do and δ capture correlated return-volatilityjump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.956 1.945 1.943 1.943 1.940

(0.005) (0.002) (0.002) (0.002) (0.001)

θ 0.320 0.313 0.309 0.316 0.271(0.002) (0.003) (0.003) (0.004) (0.002)

ξ 0.387 0.381 0.381 0.383 0.450(0.010) (0.012) (0.012) (0.012) (0.006)

ρ 0.634 0.288 0.289 0.308 0.493(0.020) (0.006) (0.006) (0.006) (0.016)

λ 1.001 0.993 0.998 0.959(0.002) (0.002) (0.002) (0.004)

µ 0.141 0.145 0.142 -0.045(0.006) (0.006) (0.006) (0.005)

σj 0.026 0.025 0.024 0.027(0.001) (0.001) (0.001) (0.001)

λy/α/do 0.999 0.997 0.116(0.001) (0.001) (0.005)

µy/β/δ 0.004 0.018 0.006(0.001) (0.003) (0.001)

Implied Volatility 41.15% 43.57% 41.47% 41.61% 40.72% 38.26%(0.004) (0.005) (0.006) (0.006) (0.006) (0.005)

RMSE 0.36 0.01 0.01 0.01 0.01 0.01

NOB 252 252 252 252 252 252

159

Table 37: Parameter Estimation for Long-Term Options

The table below displays the structural parameters and goodness-of-fit for the following option models foroptions with 180 days or more until expiration: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.891 2.914 2.449 2.118 2.324

(0.036) (0.202) (0.117) (0.076) (0.097)

θ 0.347 0.313 0.237 0.306 0.250(0.017) (0.005) (0.023) (0.005) (0.008)

ξ 1.770 1.061 0.850 0.400 0.654(0.264) (0.216) (0.194) (0.031) (0.071)

ρ 0.563 0.319 0.314 0.331 0.454(0.017) (0.014) (0.014) (0.008) (0.015)

λ 0.952 0.949 0.987 0.901(0.007) (0.007) (0.006) (0.007)

µ 0.126 0.139 0.138 -0.029(0.010) (0.011) (0.010) (0.016)

σj 0.480 0.299 0.132 0.240(0.091) (0.056) (0.022) (0.044)

λy/α/do 0.896 1.094 -0.122(0.064) (0.039) (0.039)

µy/β/δ -0.278 -0.005 0.185(0.110) (0.002) (0.065)

Implied Volatility 48.60% 58.13% 46.94% 46.90% 46.48% 43.18%(0.003) (0.011) (0.007) (0.007) (0.007) (0.006)

RMSE 51.00 41.56 36.62 36.92 35.66 36.76

NOB 654 654 654 654 654 654

160

Table 38: Parameter Estimation for Medium-Term Options

The table below displays the structural parameters and goodness-of-fit for the following option models foroptions expiring between 60 and 180 days: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.747 3.029 2.776 1.996 2.533

(0.036) (0.171) (0.132) (0.024) (0.090)

θ 0.325 0.276 0.204 0.279 0.251(0.018) (0.008) (0.036) (0.008) (0.008)

ξ 6.257 1.526 1.228 0.753 1.403(0.485) (0.186) (0.132) (0.083) (0.103)

ρ 0.004 0.096 0.098 0.075 0.130(0.023) (0.018) (0.018) (0.015) (0.020)

λ 1.144 1.150 1.192 0.964(0.015) (0.017) (0.014) (0.014)

µ 0.048 0.046 0.029 0.119(0.021) (0.021) (0.020) (0.024)

σj 1.345 1.187 0.488 0.667(0.140) (0.122) (0.081) (0.071)

λy/α/do 0.902 1.290 -0.712(0.030) (0.054) (0.061)

µy/β/δ -0.278 -0.006 -0.147(0.084) (0.006) (0.042)

Implied Volatility 64.38% 100.66% 50.82% 49.91% 51.08% 48.67%(0.006) (0.034) (0.008) (0.008) (0.008) (0.010)

RMSE 207.09 131.99 113.15 113.23 108.77 112.23

NOB 1231 1231 1231 1231 1231 1231

161

Table 39: Parameter Estimation for Short-Term Options

The table below displays the structural parameters and goodness-of-fit for the following option models foroptions with 60 days or less until expiration: (1) Black option models (B), (2) stochastic volatility (SV), (3)stochastic volatility with jumps (SVJ), (4) stochastic volatility with independent return and volatility jumps(SVDJ), (5) stochastic volatility with jumps and term structure reciprocal fit (SVJT), (6) stochastic volatilitywith correlated volatility and return jumps (DPS). The structural parameters are estimated minimizing thesum of squared difference between the market price and the model estimated price. The RMSE denoted thesum of square root of the sum of squares errors for all options estimated. The structural parameters, κ, θ,and ξ, are the stochastic volatility components representing the speed of mean reversion, the square rootof the long run mean, and the variation of the volatility V (t). The parameters λ, µ, and σj , represent thefrequency of jumps per year, the mean jump size, and the standard deviation of the jump. The parametersα and β are TSOV parameters, λy and µy are volatility jump parameters, and do and δ capture correlatedreturn-volatility jump components.Standard errors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.696 2.020 2.004 1.968 2.047

(0.107) (0.057) (0.039) (0.049) (0.040)

θ 0.394 0.319 0.214 0.289 0.371(0.102) (0.047) (0.057) (0.050) (0.020)

ξ 32.994 12.642 13.916 11.539 5.499(1.840) (1.199) (1.286) (1.162) (0.651)

ρ -0.054 0.033 0.046 0.089 0.119(0.042) (0.037) (0.037) (0.032) (0.036)

λ 2.261 2.543 2.490 1.461(0.176) (0.307) (0.280) (0.083)

µ 1.596 1.514 1.056 0.546(0.315) (0.238) (0.211) (0.195)

σj 4.000 4.380 2.988 2.111(0.429) (0.504) (0.338) (0.194)

λy/α/do 0.983 2.111 -1.863(0.008) (0.287) (0.196)

µy/β/δ -0.162 0.105 -0.402(0.073) (0.046) (0.094)

Implied Volatility 146.28% 220.82% 99.88% 91.00% 84.84% 56.83%(0.053) (0.099) (0.065) (0.064) (0.053) (0.019)

RMSE 129.02 18.72 9.95 9.84 7.47 7.81

NOB 431 431 431 431 431 431

162

Table 40: Parameter Estimation for Long-Term Options in the Winter Months

The table below displays the structural parameters and goodness-of-fit for the following option models forwinter options (December, January, and February) expiring in 180 days or more: (1) Black option models(B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility withindependent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structurereciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The struc-tural parameters are estimated minimizing the sum of squared difference between the market price and themodel estimated price. The RMSE denoted the sum of square root of the sum of squares errors for alloptions estimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components repre-senting the speed of mean reversion, the square root of the long run mean, and the variation of the volatilityV (t). The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.759 3.041 2.573 2.206 2.230

(0.039) (0.349) (0.221) (0.111) (0.098)

θ 0.466 0.349 0.250 0.329 0.243(0.046) (0.014) (0.053) (0.013) (0.015)

ξ 3.216 0.450 0.336 0.374 0.676(0.693) (0.093) (0.060) (0.100) (0.100)

ρ 0.695 0.418 0.402 0.370 0.644(0.036) (0.031) (0.032) (0.020) (0.027)

λ 0.922 0.929 0.973 0.828(0.019) (0.018) (0.016) (0.016)

µ 0.205 0.220 0.216 -0.087(0.022) (0.021) (0.017) (0.028)

σj 0.424 0.273 0.195 0.206(0.106) (0.059) (0.044) (0.042)

λy/α/do 0.973 1.199 -0.116(0.031) (0.114) (0.066)

µy/β/δ -0.034 -0.014 0.395(0.051) (0.006) (0.187)

Implied Volatility 57.89% 77.58% 58.47% 58.71% 58.29% 53.14%(0.003) (0.030) (0.015) (0.015) (0.015) (0.011)

RMSE 18.38 14.57 13.21 13.24 13.09 13.12

NOB 190 190 190 190 190 190

163

Table 41: Parameter Estimation for Medium-Term Options in the WinterMonths

The table below displays the structural parameters and goodness-of-fit for the following option models forwinter options (December, January, and February) expiring between 60 and 180 days: (1) Black optionmodels (B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatil-ity with independent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and termstructure reciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS).The structural parameters are estimated minimizing the sum of squared difference between the market priceand the model estimated price. The RMSE denoted the sum of square root of the sum of squares errorsfor all options estimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility componentsrepresenting the speed of mean reversion, the square root of the long run mean, and the variation of thevolatility V (t). The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jumpsize, and the standard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy arevolatility jump parameters, and do and δ capture correlated return-volatility jump components.Standarderrors are in parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.846 2.547 2.336 2.037 2.327

(0.069) (0.160) (0.092) (0.035) (0.146)

θ 0.278 0.311 0.092 0.306 0.257(0.015) (0.012) (0.057) (0.012) (0.012)

ξ 2.777 0.552 0.321 0.251 0.861(0.626) (0.159) (0.042) (0.029) (0.106)

ρ -0.214 0.079 0.045 0.030 -0.051(0.051) (0.036) (0.038) (0.035) (0.044)

λ 1.210 1.228 1.204 1.005(0.035) (0.037) (0.025) (0.054)

µ -0.139 -0.137 -0.138 0.038(0.025) (0.025) (0.025) (0.048)

σj 0.644 0.560 0.194 0.258(0.129) (0.110) (0.035) (0.077)

λy/α/do 0.973 1.138 -0.323(0.015) (0.088) (0.105)

µy/β/δ -0.006 -0.002 -0.286(0.014) (0.005) (0.074)

Implied Volatility 66.01% 84.65% 62.24% 61.42% 62.90% 62.30%(0.005) (0.036) (0.014) (0.014) (0.013) (0.040)

RMSE 32.46 24.53 21.12 21.13 19.88 20.89

NOB 268 268 268 268 268 268

164

Table 42: Parameter Estimation for Short-Term Options in the Winter Months

The table below displays the structural parameters and goodness-of-fit for the following option models forwinter options (December, January, and February) expiring in 60 days or less: (1) Black option models(B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility withindependent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structurereciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The struc-tural parameters are estimated minimizing the sum of squared difference between the market price and themodel estimated price. The RMSE denoted the sum of square root of the sum of squares errors for alloptions estimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components repre-senting the speed of mean reversion, the square root of the long run mean, and the variation of the volatilityV (t). The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.880 1.850 1.881 1.903 1.898

(0.036) (0.033) (0.018) (0.015) (0.009)

θ 0.287 0.267 0.271 0.332 0.281(0.004) (0.041) (0.022) (0.037) (0.008)

ξ 4.312 1.458 1.890 1.254 0.660(2.602) (0.350) (0.673) (0.344) (0.082)

ρ -0.592 0.027 -0.001 -0.036 -0.467(0.098) (0.108) (0.110) (0.108) (0.102)

λ 2.146 1.794 2.098 1.146(0.342) (0.182) (0.388) (0.063)

µ 0.181 0.369 0.150 -0.145(0.228) (0.311) (0.211) (0.170)

σj 0.135 0.133 0.133 0.013(0.020) (0.020) (0.021) (0.011)

λy/α/do 0.987 1.119 -0.263(0.006) (0.097) (0.088)

µy/β/δ 0.047 -0.010 -0.122(0.056) (0.018) (0.121)

Implied Volatility 82.90% 94.44% 98.29% 102.38% 96.66% 78.13%(0.016) (0.082) (0.096) (0.123) (0.087) (0.013)

RMSE 0.33 0.41 0.27 0.28 0.27 0.30

NOB 53 53 53 53 53 53

165

Table 43: Parameter Estimation for Long-Term Options in the Spring Months

The table below displays the structural parameters and goodness-of-fit for the following option models forspring options (March, April, and May) expiring in 180 days or more: (1) Black option models (B), (2)stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility with indepen-dent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structure reciprocalfit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The structural pa-rameters are estimated minimizing the sum of squared difference between the market price and the modelestimated price. The RMSE denoted the sum of square root of the sum of squares errors for all optionsestimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components representingthe speed of mean reversion, the square root of the long run mean, and the variation of the volatility V (t).The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.921 1.941 1.931 1.935 1.935

(0.005) (0.003) (0.004) (0.004) (0.001)

θ 0.305 0.296 0.299 0.292 0.275(0.005) (0.005) (0.004) (0.005) (0.003)

ξ 0.587 0.460 0.467 0.466 0.465(0.036) (0.014) (0.015) (0.014) (0.008)

ρ 0.404 0.266 0.269 0.300 0.263(0.020) (0.017) (0.017) (0.010) (0.017)

λ 0.974 0.967 0.978 0.961(0.004) (0.006) (0.004) (0.005)

µ 0.077 0.081 0.086 0.007(0.008) (0.008) (0.007) (0.007)

σj 0.041 0.041 0.042 0.036(0.004) (0.004) (0.004) (0.003)

λy/α/do 0.998 0.997 0.050(0.002) (0.002) (0.006)

µy/β/δ 0.005 -0.010 0.006(0.002) (0.003) (0.003)

Implied Volatility 43.90% 49.27% 43.52% 42.99% 43.91% 41.01%(0.004) (0.005) (0.007) (0.007) (0.006) (0.006)

RMSE 0.41 0.06 0.06 0.06 0.06 0.05

NOB 247 247 247 247 247 247

166

Table 44: Parameter Estimation for Medium-Term Options in the SpringMonths

The table below displays the structural parameters and goodness-of-fit for the following option models forspring options (March, April, and May) expiring between 60 and 180 days: (1) Black option models (B), (2)stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility with indepen-dent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structure reciprocalfit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The structural pa-rameters are estimated minimizing the sum of squared difference between the market price and the modelestimated price. The RMSE denoted the sum of square root of the sum of squares errors for all optionsestimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components representingthe speed of mean reversion, the square root of the long run mean, and the variation of the volatility V (t).The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.929 1.932 1.923 1.937 1.922

(0.016) (0.009) (0.008) (0.005) (0.006)

θ 0.275 0.307 0.304 0.316 0.289(0.008) (0.010) (0.006) (0.008) (0.005)

ξ 1.577 0.439 0.478 0.415 0.433(0.495) (0.034) (0.056) (0.034) (0.018)

ρ 0.162 0.094 0.115 0.140 0.085(0.036) (0.030) (0.029) (0.026) (0.031)

λ 1.099 1.093 1.086 0.977(0.018) (0.020) (0.021) (0.011)

µ 0.048 0.066 0.029 -0.062(0.021) (0.028) (0.019) (0.008)

σj 0.067 0.067 0.064 0.042(0.007) (0.007) (0.006) (0.004)

λy/α/do 0.999 0.998 -0.102(0.002) (0.005) (0.051)

µy/β/δ 0.004 0.025 0.012(0.011) (0.013) (0.003)

Implied Volatility 57.33% 64.33% 57.61% 57.77% 57.20% 52.44%(0.006) (0.020) (0.009) (0.013) (0.009) (0.008)

RMSE 4.44 1.98 1.71 1.71 1.69 1.73

NOB 348 348 348 348 348 348

167

Table 45: Parameter Estimation for Short-Term Options in the Spring Months

The table below displays the structural parameters and goodness-of-fit for the following option modelsfor spring options (March, April, and May) expiring in 60 days or less: (1) Black option models (B), (2)stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility with indepen-dent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structure reciprocalfit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The structural pa-rameters are estimated minimizing the sum of squared difference between the market price and the modelestimated price. The RMSE denoted the sum of square root of the sum of squares errors for all optionsestimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components representingthe speed of mean reversion, the square root of the long run mean, and the variation of the volatility V (t).The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.818 1.870 1.904 1.938 2.019

(0.059) (0.025) (0.022) (0.019) (0.107)

θ 0.314 0.368 0.279 0.285 0.298(0.028) (0.069) (0.036) (0.032) (0.017)

ξ 8.591 2.231 2.434 1.003 1.554(2.249) (0.365) (0.468) (0.191) (0.419)

ρ 0.112 0.063 0.078 0.171 0.260(0.070) (0.068) (0.066) (0.055) (0.057)

λ 1.770 1.767 1.577 1.183(0.180) (0.155) (0.123) (0.090)

µ 1.406 1.243 0.323 0.599(0.328) (0.295) (0.069) (0.575)

σj 2.931 2.887 1.459 1.104(0.787) (0.777) (0.453) (0.323)

λy/α/do 0.988 1.108 -0.991(0.006) (0.081) (0.320)

µy/β/δ -0.114 0.002 0.117(0.123) (0.035) (0.208)

Implied Volatility 72.97% 94.24% 90.27% 77.44% 52.69% 49.22%(0.041) (0.112) (0.116) (0.100) (0.022) (0.022)

RMSE 14.99 6.16 4.09 4.10 3.46 3.94

NOB 139 139 139 139 139 139

168

Table 46: Parameter Estimation for Long-Term Options in the SummerMonths

The table below displays the structural parameters and goodness-of-fit for the following option models forsummer options (June, July, and August) expiring in 180 days or more: (1) Black option models (B), (2)stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility with indepen-dent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structure reciprocalfit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The structural pa-rameters are estimated minimizing the sum of squared difference between the market price and the modelestimated price. The RMSE denoted the sum of square root of the sum of squares errors for all optionsestimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components representingthe speed of mean reversion, the square root of the long run mean, and the variation of the volatility V (t).The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.942 1.963 1.957 1.956 1.941

(0.012) (0.006) (0.005) (0.005) (0.003)

θ 0.335 0.351 0.326 0.353 0.274(0.005) (0.007) (0.007) (0.008) (0.006)

ξ 0.496 0.257 0.247 0.235 0.375(0.156) (0.022) (0.022) (0.022) (0.013)

ρ 0.679 0.308 0.327 0.345 0.579(0.039) (0.025) (0.023) (0.014) (0.030)

λ 1.000 0.988 0.994 0.950(0.011) (0.007) (0.005) (0.009)

µ 0.111 0.118 0.129 -0.085(0.016) (0.016) (0.015) (0.013)

σj 0.042 0.039 0.032 0.038(0.008) (0.008) (0.006) (0.004)

λy/α/do 1.001 1.006 0.048(0.002) (0.009) (0.020)

µy/β/δ 0.010 0.024 0.018(0.004) (0.004) (0.004)

Implied Volatility 41.95% 44.48% 40.00% 40.43% 39.38% 37.53%(0.005) (0.014) (0.011) (0.011) (0.011) (0.010)

RMSE 1.10 0.82 0.79 0.79 0.77 0.78

NOB 146 146 146 146 146 146

169

Table 47: Parameter Estimation for Medium-Term Options in the SummerMonths

The table below displays the structural parameters and goodness-of-fit for the following option models forsummer options (June, July, and August) expiring between 60 and 180 days: (1) Black option models(B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility withindependent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structurereciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The struc-tural parameters are estimated minimizing the sum of squared difference between the market price and themodel estimated price. The RMSE denoted the sum of square root of the sum of squares errors for alloptions estimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components repre-senting the speed of mean reversion, the square root of the long run mean, and the variation of the volatilityV (t). The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.785 3.072 2.594 1.944 2.660

(0.079) (0.421) (0.197) (0.015) (0.192)

θ 0.365 0.304 0.257 0.288 0.271(0.042) (0.011) (0.022) (0.009) (0.016)

ξ 5.686 1.410 1.078 0.509 0.917(0.805) (0.425) (0.258) (0.071) (0.121)

ρ 0.215 0.207 0.202 0.180 0.355(0.042) (0.033) (0.032) (0.028) (0.033)

λ 1.110 1.086 1.148 0.957(0.027) (0.017) (0.022) (0.016)

µ 0.063 0.063 0.063 0.028(0.027) (0.029) (0.026) (0.032)

σj 1.204 1.082 0.299 0.861(0.228) (0.191) (0.043) (0.166)

λy/α/do 0.875 1.326 -0.802(0.057) (0.128) (0.124)

µy/β/δ -0.455 -0.023 0.032(0.209) (0.007) (0.096)

Implied Volatility 54.41% 84.08% 46.57% 44.93% 46.93% 39.79%(0.009) (0.049) (0.012) (0.010) (0.012) (0.008)

RMSE 49.95 31.28 25.54 25.60 24.55 25.35

NOB 354 354 354 354 354 354

170

Table 48: Parameter Estimation for Short-Term Options in the SummerMonths

The table below displays the structural parameters and goodness-of-fit for the following option models forsummer options (June, July, and August) expiring in 60 days or less: (1) Black option models (B), (2)stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility with indepen-dent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structure reciprocalfit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The structural pa-rameters are estimated minimizing the sum of squared difference between the market price and the modelestimated price. The RMSE denoted the sum of square root of the sum of squares errors for all optionsestimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components representingthe speed of mean reversion, the square root of the long run mean, and the variation of the volatility V (t).The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 0.975 1.780 1.929 1.619 2.006

(0.081) (0.067) (0.069) (0.056) (0.044)

θ 0.140 0.254 0.212 0.317 0.415(0.028) (0.120) (0.171) (0.131) (0.046)

ξ 50.159 11.787 14.113 11.076 7.356(3.529) (1.960) (2.221) (1.997) (1.244)

ρ -0.520 -0.246 -0.193 -0.147 0.175(0.069) (0.063) (0.064) (0.050) (0.073)

λ 2.996 3.437 3.333 2.414(0.211) (0.502) (0.278) (0.205)

µ 0.329 0.157 0.173 1.008(0.198) (0.114) (0.126) (0.172)

σj 7.413 8.617 5.522 3.365(1.004) (1.282) (0.837) (0.468)

λy/α/do 0.980 4.265 -4.437(0.022) (0.874) (0.392)

µy/β/δ 0.004 0.008 -1.210(0.158) (0.100) (0.179)

Implied Volatility 157.29% 337.69% 48.99% 47.16% 48.44% 34.71%(0.086) (0.213) (0.079) (0.084) (0.087) (0.022)

RMSE 59.40 10.37 4.59 4.68 3.21 3.20

NOB 136 136 136 136 136 136

171

Table 49: Parameter Estimation for Long-Term Options in the Fall Months

The table below displays the structural parameters and goodness-of-fit for the following option models forfall options (September, October, and November) expiring in 180 days or more: (1) Black option models(B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility withindependent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structurereciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The struc-tural parameters are estimated minimizing the sum of squared difference between the market price and themodel estimated price. The RMSE denoted the sum of square root of the sum of squares errors for alloptions estimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components repre-senting the speed of mean reversion, the square root of the long run mean, and the variation of the volatilityV (t). The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.949 7.591 4.736 2.739 4.527

(0.298) (1.416) (0.811) (0.605) (0.768)

θ 0.189 0.188 -0.191 0.192 0.128(0.084) (0.016) (0.137) (0.018) (0.059)

ξ 4.450 6.179 4.608 0.556 1.754(1.372) (1.781) (1.640) (0.072) (0.554)

ρ 0.507 0.253 0.203 0.288 0.338(0.034) (0.061) (0.061) (0.027) (0.054)

λ 0.820 0.826 0.997 0.753(0.033) (0.033) (0.033) (0.032)

µ 0.109 0.161 0.126 0.112(0.049) (0.064) (0.059) (0.116)

σj 2.937 1.732 0.466 1.401(0.695) (0.439) (0.155) (0.346)

λy/α/do 0.112 1.280 -1.044(0.551) (0.168) (0.275)

µy/β/δ -2.406 -0.024 0.563(0.929) (0.007) (0.299)

Implied Volatility 51.61% 62.35% 40.54% 40.46% 36.85% 34.30%(0.007) (0.031) (0.025) (0.032) (0.025) (0.024)

RMSE 31.11 26.12 22.56 22.83 21.74 22.80

NOB 74 74 74 74 74 74

172

Table 50: Parameter Estimation for Medium-Term Options in the Fall Months

The table below displays the structural parameters and goodness-of-fit for the following option models forfall options (September, October, and November) expiring in 60 to 180 days: (1) Black option models(B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility withindependent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structurereciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The struc-tural parameters are estimated minimizing the sum of squared difference between the market price and themodel estimated price. The RMSE denoted the sum of square root of the sum of squares errors for alloptions estimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components repre-senting the speed of mean reversion, the square root of the long run mean, and the variation of the volatilityV (t). The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 1.338 4.825 4.501 2.074 3.329

(0.102) (0.507) (0.519) (0.099) (0.282)

θ 0.379 0.160 0.102 0.190 0.166(0.059) (0.029) (0.149) (0.030) (0.027)

ξ 16.386 3.988 3.261 1.997 3.790(1.565) (0.590) (0.469) (0.350) (0.392)

ρ -0.258 -0.019 -0.008 -0.101 0.084(0.051) (0.046) (0.046) (0.034) (0.051)

λ 1.169 1.216 1.356 0.908(0.039) (0.059) (0.041) (0.029)

µ 0.211 0.177 0.147 0.544(0.078) (0.072) (0.073) (0.086)

σj 3.856 3.362 1.561 1.618(0.516) (0.457) (0.354) (0.210)

λy/α/do 0.734 1.756 -1.745(0.112) (0.151) (0.168)

µy/β/δ -0.673 -0.027 -0.463(0.265) (0.019) (0.121)

Implied Volatility 83.86% 183.50% 35.33% 34.02% 35.95% 41.14%(0.021) (0.119) (0.021) (0.020) (0.025) (0.016)

RMSE 121.34 75.12 65.61 65.62 63.45 65.08

NOB 271 271 271 271 271 271

173

Table 51: Parameter Estimation for Short-Term Options in the Fall Months

The table below displays the structural parameters and goodness-of-fit for the following option models forfall options (September, October, and November) expiring in 60 days or less: (1) Black option models(B), (2) stochastic volatility (SV), (3) stochastic volatility with jumps (SVJ), (4) stochastic volatility withindependent return and volatility jumps (SVDJ), (5) stochastic volatility with jumps and term structurereciprocal fit (SVJT), (6) stochastic volatility with correlated volatility and return jumps (DPS). The struc-tural parameters are estimated minimizing the sum of squared difference between the market price and themodel estimated price. The RMSE denoted the sum of square root of the sum of squares errors for alloptions estimated. The structural parameters, κ, θ, and ξ, are the stochastic volatility components repre-senting the speed of mean reversion, the square root of the long run mean, and the variation of the volatilityV (t). The parameters λ, µ, and σj , represent the frequency of jumps per year, the mean jump size, and thestandard deviation of the jump. The parameters α and β are TSOV parameters, λy and µy are volatilityjump parameters, and do and δ capture correlated return-volatility jump components.Standard errors arein parenthesis

Parameters B SV SVJ SVJT SVDJ DPSκ 2.318 2.522 2.229 2.395 2.136

(0.373) (0.189) (0.118) (0.162) (0.051)

θ 0.821 0.336 0.110 0.214 0.433(0.381) (0.060) (0.051) (0.095) (0.045)

ξ 52.628 30.635 32.214 28.733 9.884(2.450) (3.227) (3.366) (3.059) (1.772)

ρ 0.576 0.363 0.338 0.349 0.152(0.050) (0.058) (0.058) (0.053) (0.051)

λ 1.903 2.603 2.623 0.727(0.544) (0.964) (0.970) (0.106)

µ 3.863 3.944 3.338 0.199(1.060) (0.755) (0.731) (0.036)

σj 2.648 2.705 2.871 2.638(0.265) (0.300) (0.452) (0.153)

λy/α/do 0.950 1.097 -0.451(0.014) (0.056) (0.266)

µy/β/δ -0.517 0.507 -0.160(0.126) (0.162) (0.053)

Implied Volatility 243.52% 279.16% 169.48% 151.37% 158.94% 81.60%(0.109) (0.120) (0.148) (0.157) (0.142) (0.050)

RMSE 54.79 1.79 1.02 0.80 0.55 0.39

NOB 114 114 114 114 114 114

174

Table 52: Market Price(s) of Risk

The table below shows the estimates for the market price(s) of risk. λs is the market price of risk. λσ

is the market price of volatility risk. λj and λjv are the market price of return-jump intensity risk andmarket price of volatility-jump intensity risk respectively. (SV) is the stoachstic volatility model, (SVJ) isthe stochastic volatility with jumps and (SVDJ) stochastic volatility with independent return and volatilityjumps. T-Stats are in parentheses. σ̂ is the average spot volatility.

Model λs λσ λj λjv σ̂

SV -0.37 -17.96 76.76%(1.83) (27.35)

SVJ 0.08 -5.15 0.42 51.91%(0.81) (12.04) (41.97)

SVDJ -0.04 -4.92 0.27 0.49 52.65%(0.62) (12.47) (16.86) (19.87)

175

Appendices

176

Appendix A

Bias in Black-Scholes/Black Volatiltiy

A.1 Non-recombining Bushy Lattice Framework

For node i, we have the given price Si, r,σi, and µi. From the volatility

we calculate the up, down, risk neutral, and objective probabilities as follows

up∗ = e(σ∗i+1

√4t)

down∗ = e(−σ∗i+1

√4t)

up = e(σi+1√4t)

down = e(−σi+1√4t)

with the initial risk neutral and objective probabilities equal to one

another at the starting node. At the subsequent nodes it is necessary to keep

track of two trees, since the price and volatilities for the risk neutral and

objective probabilities are different. From the price at node i we infer the

volatility as follows for both distribution at the up node as.

177

risk neutral:

dz∗2i =

S∗2i−S∗iS∗i

− r4tσ∗i

σ∗22i = σ∗2i + κ(θ − σ∗2i ) ∗ 4t− ξσ∗2i ∗ dz∗2i

S∗2(i+1) = up ∗ S∗i+1

objective:

dz2i =S2i−Si

Si− µ2i4tσi

σ22i = σ2

i + (κ(θ − σ2i ) + ξλσ2

i )4t− ξσ2i dz2i

µ2(i+1) = r + λσi+1

S2(i+1) = up ∗ Si+1

For the bottom node we have risk neutral:

dz∗2i =

S∗2i+1−S∗iS∗i

− r4tσ∗i

σ∗22i+1 = σ∗2i + κ(θ − σ∗2i ) ∗ 4t− ξσ∗2i ∗ dz∗2i

S∗2(i+1)+1 = down ∗ S∗i+1

objective:

dz2i =

S2i+1−Si

Si− µ2i4tσi

σ22i+1 = σ2

i + (κ(θ − σ2i ) + ξλσ2

i )4t− ξσ2i dz2i

µ2(i+1)+1 = r + λσi+1

S2(i+1)+1 = down ∗ Si+1

178

The calculation of realized term volatility is a probability weighted

average of the log of the change in stock prices over the initial stock prices.

This requires maintaining a path of probabilities for each of the final nodes.

The resulting volatility is thus.

√∑τi=1 ((ln Si

S0− µ)2)φ

√T

(A.1)

where µ is the probability weighted average of log price changes, τ are

the number of nodes, φ is the probability of arrival at any particular node, and

T is the time to maturity. For the implied volatility, we solve for the option

price in the typical fashion. We solve for the call value at t = 0 by solving

for the payoff at each node backwards through the tree. With the call value

we then invert the Black-Scholes formula to find the implied volatility of the

option.

A.2 Demonstrating greater risk-neutral volatility thanreal-world volatility with negative market price ofvolatiltiy risk

To show that when the market price of volatility risk is negative the

resulting change in volatility is greater for risk-neutral versus real-world volatil-

ity, I need only demonstrate that 4σ2RN ≥ 4σ2

RW where 4σ2RN is the risk-

neutral variance and 4σ2RW is the real-world variance.

Assuming perfect negative correlation note the real-world equity vari-

179

ance below:

4σ2RW = [κ(θ − σ2) + λξσ2]4t+ ξσ[

µ4t− 4SS

σ]

4σ2RW = [κ(θ − σ2) + λξσ2]4t+ ξσ[

(r + λσ)4t− 4SS

σ]

4σ2RW = [C + λξσA]4t+B

where

A = (σ + 1)

B = ξ(r − 4SS

)

C = κ(θ − σ2)

Now assume that θ = σ2 such that C = 0, a negative λ results in A

dampining the effect of B, thus muting 4σ2RW . For the risk-neutral process,

A = 0, and B fully impacts4σ2RN .On average through time it must be the case

that C = 0 given the mean-reverting nature of volatiltiy. Thus4σ2RN ≥ 4σ2

RW

180

Appendix B

Characteristic Functions for Candidate Option

Pricing Models

B.1 Correlated Double-Jump Model

For completeness we present the characteristic function as presented by

Duffie, Pan and Singleton (2000) with the correction for option valuation on

a futures contract.

A(τ ;φ) =θv

σ2v

(ξ + iφσv − κv)τ (B.1)

− 2θv

σ2v

log

(1− (ξ + iφσv − κv)(1− e−ξτ)

)(B.2)

− iφλx,y

(exp(do+ 1

2σ2

x,y)

1− µyδx,y

− 1

)τ − λx,yτ (B.3)

+λx,y(2ξ − b)exp(iφdo− 1

2φ2σ2

x,y)τ

p(B.4)

+2λx,yµyiφ(iφ− 1)exp(iφdo− 1

2φ2σ2

x,y)

pqlog

(p+ qe−ξτ

p+ q

)(B.5)

(B.6)

and,

B(τ ;φ) =iφ(iφ− 1)(1− e−ξτ )

2ξ − (ξ + iφρσv − κv)(1− e−ξτ )

181

where ξ, p, q and b are defined

ξ(φ) =√

(ξ + iφσv − κv)2 − iφ(iφ− 1)σ2v)

p = 2ξ(1− µyiφδx,y)− q

b = ξ + iφρσv − κv

q = iφ(iφ− 1)µy + b(1− µyiφδx,y)

B.2 Independent Double-Jump Model

For the SVDJ model where return-jumps and volatility-jumps are in-

dependnet the characteristic functions are shown below:

A(τ ;φ) =θv

σ2v

(ξ + iφσv − κv)τ − λyτ

− 2θv

σ2v

log

(1− (ξ + iφσv − κv)(1− e−ξτ)

)+

λy(2ξ − b)

(2ξ − q)τ +

2λy(q − b)

q(2ξ − q)log

(2ξ − q(1− e−ξτ )

)+ λx

[(1 + µx)

iφe12iφ(iφ−1)σ2

x − 1]τ − iφλxµxτ

B(τ ;φ) =iφ(iφ− 1)(1− e−ξτ )

2ξ − (ξ + iφρσv − κv)(1− e−ξτ )(B.7)

182

where ξ, q and b are defined

ξ(φ) =√

(ξ + iφσv − κv)2 − iφ(iφ− 1)σ2v)

b = ξ + iφρσv − κv

q = iφ(iφ− 1)µy + b

B.3 Barone-Adesi and Whaley Analytical Approxima-tion for American Option Prices

Note that the American and European option prices both satisfy the

Black-Scholes differential equation:

∂ν

∂t+ (r − q)S

∂ν

∂S+

1

2σ2S2 ∂

∂S2= rν (B.8)

Let

ν = h(τ)g(S, h) (B.9)

and substitute

betaS∂g

∂S+ S2 ∂

2g

∂S2− α

hg − (1− h)α

∂g

∂h= 0 (B.10)

where

τ = T − t

h(τ) = 1− e−rτ

α =2r

σ2

β =2(r − q)

σ2

183

The final term on the left-hand side is close to zero and can be ignored.

When τ is large, 1− h is close to zero; when τ is small, ∂g∂h

is close to zero.

Let the American call and put price at time τ be equal to C(S, t) and

P (S, t), where S is the stock price. Let c(S, t) and p(S, t) be equal to the

European call and put prices. Equation B.10 can be solved using standard

techniques. After boundary conditions have been found, the American Call is

equal to

C(S, t) =

{c(S, t) + A2(

SS∗

)γ2 , S < S∗

S −X, S ≥ S∗(B.11)

where S∗ is the critical price of the stock above which the option should

be exercised. It is estimated by solving

S∗ −X = c(S∗, t) +[1− e−q(T−t)N [d1(S∗)]

] S∗γ2

(B.12)

iteratively. For the put option, the valuation formula is

P (S, t) =

{p(S, t) + A2(

SS∗∗

)γ1 , S > S∗

X − S, S ≤ S∗(B.13)

where S∗∗ is the critical price of the stock below which the option should

be exercised. It is estimated by solving iteratively

X − S∗∗ = p(S∗∗, t) +[1− e−q(T−t)N [−d1(S∗∗)]

] S∗∗γ2

(B.14)

184

where

γ1 =

[−(β − 1)−

√(B − 1)2 + 4α

h

]2

γ2 =

[−(β − 1) +

√(B − 1)2 + 4α

h

]2

A1 = −(S∗∗

γ1

)(1− e−q(T−t)N [−d1(S∗∗)]

)A2 = −

(S∗

γ2

)(1− e−q(T−t)N [−d1(S∗)]

)While this formulation is for stock options, this quadratic approach can

easily be applied to options on futures contracts as the options are analogous

to stock options.

185

Index

Abstract, vi

Acknowledgments, v

Appendices, 176

Appendix

Bias in Black-Scholes/Black Volatiltiy,

177

Bibliography, 195

Bibliography, 187

Black implied volatility, 33

Black-Scholes, 1

Characteristic Functions for Candi-

date Option Pricing Models,

181

commands

environments

figure, 114–124

table, 125–129, 132, 134, 136,

137, 176

Dedication, iv

double-jump option model, 80

Empirical Performance of Option Mod-

els for Natural Gas and Es-

timation of the Market Price(s)

of Risk, 74

Estimating the bias, 22

Estimation of λσ, 66

Estimation of the Bias in BSIV/BIV,

19

Estimation Using Mean Reverting

Framework, 65

Evidence on the Market Price of Volatil-

ity Risk, 9

Independent Double Jumps and TSOV

considerations, 85

Introduction, 1

Mean-Reversion in Stochastic Volatil-

ity, 103

Modeling Issues, 80

Monte Carlo Simulation, 37

Monte Carlo Simulation and Esti-

mation of the Market Price

of Volatility Risk, 36

Out of sample pricing performance,

101

Parameter Estimation, including Mar-

ket Price of Risk, 106

Simulation within a Simulation, 61

Stochastic Volatility, 14

Structural Parameter Estimation and

Model Performance, 94

Tables and Figures, 113

The Bias in Black-Scholes/Black Im-

plied Volatility, 14

TSOV, 26

Understanding the volatility in gas

markets, 89

186

Bibliography

1. Ait-Sahalia, Y., and A. Lo, 1998, Nonparametric estimation of state-

price densities implicit in financial prices, Journal of Finance 53, No. 2,

499-548.

2. Anderson, T., Bollerslev, T., 1998. Answering the Skeptics: Yes, Stan-

dard Volatility Models do provide Accurate Forecasts. International Eco-

nomic Review 39, 885-905

3. Andersen, T., T. Bollerslev, F. Diebold, and H. Ebens, 2001. The dis-

tribution of stock return volatility. Journal of Financial Economics 61.

4. Andersen, T., L. Benzoni, J. Lund, 2002, An empirical investigation of

continuous-time equity return models, Journal of Finance 57, 1239-1284.

5. Bakshi, G., and C. Cao, 2003, Risk-Neutral Kurtosis, Jumps, and Option

Pricing: Evidence from 100 Most Actively Traded Firms on the CBOE,

Working Paper, University of Maryland

6. Bakshi, G., Cao, C., Chen, Z., 1997. Empirical performance of alterna-

tive option pricing models. Journal of Finance 52, 2003-2049.

7. Bakshi, G., C. Cao, and Z. Chen, 2000, Pricing and hedging long-term

options, Journal of Econometrics 94, 277-318.

187

8. Bakshi, G., Kapadia, N., 2001. Delta-hedged gains and the pricing of

volatility risk. Working paper, University of Massachusetts, Amherst.

9. Bakshi, G., N. Kapadia, D. Madan, 2003, Stock return characteristics,

skew laws, and the differential pricing of individual equity options, Re-

view of Financial Studies 16 (1), 101-143.

10. Ball, C., and W. Torous, 1985, On jumps in common stock prices and

their impact on call option pricing, Journal of Finance 40, 155-173.

11. Barone-Adesi, G., and R. Whaley, 1987, Efficient analytic approximation

of American option values, Journal of Finance 42, 301-320.

12. Bates, D., 1996. Jumps and Stochastic Volatility: Exchange Rate Pro-

cesses Implicit in Deutsche Mark Options. Review of Financial Studies

9, 69-107.

13. Bates, D., 2000. Post 87’ crash fears in S&P 500 futures options. Journal

of Econometrics 94, 181-238

14. Benzoni, L. (1998). Pricing options under stochastic volatility: An

econometric analysis. Working paper, Kellogg Graduate School of Man-

agement, Northwestern University.

15. Black, F., and M. Scholes, 1973, The pricing of options and corporate

liabilities, Journal of Political Economy 81, 637-659.

188

16. Black, F., 1976. Studies of stock price volatility changes. Proceedings

of the 1976 Meetings of the Business and Economics Statistics Section,

American Statistical Association, pp. 177-181.

17. Buraschi, A., and J. Jackwerth, 2001, ”The price of a smile: Hedging

and spanning in option markets,” Review of Financial Studies 14, No.2,

495-527

18. Canina, L. and S. Figlewski, 1993. The information content of Implied

Volatility. The Review of Financial Studies 6, 659-681.

19. Carr, P., H. Geman, D. Madan, and M. Yor, 2002, The fine structure of

asset returns: an empirical investigation, Journal of Business 75, Volume

2, 19-37.

20. Carr, P., and L. Wu, 2002, The finite moment log stable process and

option pricing, Journal of Finance (forthcoming).

21. Chernov, M. and E. Ghysels (2000). A study towards a unified approach

to the joint estimation of objective and risk neutral measures for the

purpose of options valuation. Journal of Financial Economics 56, 407-

458.

22. Christensen, B and N. Prabhala, 1998, ”The relationship between im-

plied and realized volatility,” Journal of Financial Economics 50, 125-150

23. Christoffersen, P and K. Jacobs, 2001, ”The Importance of the Loss

Function in Option Pricing,” McGill Working Paper

189

24. Coval, J., and T.Shumway, 2000, ”Expected Option Returns,” Journal

of Finance (forthcoming)

25. Cox, J. C., J. E. Ingersoll, and S. A. Ross, 1985. A theory of the term

structure of interest rates. Econometrica 53 (2), 385-407.

26. Das, S., 2002, The surprise element: jumps in interest rates, Journal of

Econometrics 106, 27-65.

27. Dennis, P., and S. Mayhew, 2002, Implied volatility skews: evidence from

options on individual securities, Journal of Financial and Quantitative

Analysis 37, No. 3, 471-493.

28. Dincerler, C., Ronn, E., 2001. Risk Premia and Price Dynamics in

Electric Power Markets. University of Texas working paper.

29. Duffie, D., J. Pan, and K. Singleton, 2000, Transform analysis and asset

pricing for affine jump-diffusions, Econometrica 68, 1343-1376.

30. Duffie, D. and K. Singleton, 1993, Simulated moments estimation of

markov models of asset prices, Econometrica 61, 929-952.

31. Dumas, B., J. Fleming, R. Whaley, 1998, Implied volatility functions:

empirical tests, Journal of Finance, 53 (6), 2059-2106.

32. Eberlein, E., U. Keller, K. Prause, 1998, New insights into smile, mis-

pricing, and value at risk: the hyperbolic model, Journal of Business 71,

No. 2, 371-405.

190

33. Eichenbaum, M., L. Hansen, K. Singleton, 1988, A time series analysis

of representative agent models of consumption and leisure choice under

uncertainty, Quarterly Journal of Economics, No. 1 (February), 51-78.

34. Eraker, B., 2001. Do stock prices and volatility jump? reconciling evi-

dence from spot and option prices. Working paper, Graduate School of

Business, University of Chicago

35. Eraker, B., M. Johannes, N. Polson, 2002, The impact of jumps in volatil-

ity and returns, Journal of Finance (forthcoming).

36. Fama, E., and J. McBeth, 1973, Risk, return, and equilibrium: empirical

tests, Journal of Political Economy 81, 607-636.

37. Gallant, A. R. and G. Tauchen, 1998. Reprojecting partially observed

systems with application to interest rate diffusions. Journal of American

Statistical Association 93,10-24.

38. Hansen, L., 1982, Large sample properties of generalized method of mo-

ments estimators, Econometrica 50, 1029-1084.

39. Hansen, B., 1992, The likelihood ratio test under nonstandard condi-

tions: testing the Markov switching model of GNP, Journal of Applied

Econometrics 7, S61-S82.

40. Heston, S., 1993. A closed-form solution of options with stochastic

volatility with applications to bond and currency options. The Review

of Financial Studies 6, 327-343.

191

41. Heston, S., and S. Nandi, 2000, A closed-form GARCH option valuation

model, Review of Financial Studies 13, 585-625.

42. Hentschel, L., 2002. Errors in Implied Volatility Estimation. Forthcom-

ing in the Journal of Financial and Quantitative Analysis

43. Huang, J., and L. Wu, 2002, Specification analysis of option pricing mod-

els based on time-changed Levy processes, mimeo, Fordham University.

44. Hull, J., White, A., 1987. The pricing of options on assets with stochastic

volatilities. Journal of Finance 42, 281-300.

45. Jackwerth, J. C. and M. Rubinstein, 1996. Recovering probability dis-

tributions from option prices. Journal of Finance 51, 1611-1631.

46. Jorion, P., 1995. Predicting volatility in the foreign exchange markets.

Journal of Finance 6, 327-343.

47. Jones, C., 2001. The Dynamics of Stochastic Volatility: Evidence from

the underlying and options markets. Unpublished paper, Simon School,

University of Rochester, Rochester, NY.

48. Kendall, M., and A. Stuart, 1977, The Advanced Theory of Statistics,

Volume 1, McMillan Publishing Co. New York.

49. Lamoureux, C.G., Lastrapes, W., 1993. Forecasting stock return vari-

ance: towards understanding stochastic implied volatility. Review of

Financial Studies 6, 293-326.

192

50. Longstaff, F., 1995, Option pricing and the martingale restriction, Re-

view of Financial Studies 8, No. 4, 1091-1124.

51. Madan, D., P. Carr, and E. Chang, 1998, The variance gamma process

and option pricing, European Journal of Finance 1, 39-55.

52. Merton, R., 1976, Option pricing when underlying stock returns are

discontinuous, Journal of Financial Economics 3, 125-144.

53. Newey, W., and K. West, 1987, A simple positive semi-definite het-

eroskedasticity and autocorrelation consistent covariance matrix, Econo-

metrica 55 (4), 703-708.

54. Pan, J., 2000. Jump-Diffusion Models of Asset Prices: Theory and Em-

pirical Evidence. Ph. D. Thesis, Graduate School of Business, Stanford

University.

55. Pan, J., 2002, The jump-risk premia implicit in options: evidence from

an integrated time-series study, Journal of Financial Economics 63, No.

1, 3-50.

56. Rubinstein, M., 1985, Nonparametric tests of alternative option pricing

models using all reported trades and quotes on the 30 most active CBOE

options classes from August 23, 1976 through August 31, 1978, Journal

of Finance 40, 455-480.

57. Rubinstein, M., 1994. Implied binomial trees. Journal of Finance 49,

771-818.

193

58. Singleton, K., 2001, Estimation of affine asset pricing models using the

empirical characteristic function, Journal of Econometrics, Vol. 102,

111-141.

59. Stanton, R., 1997. A Nonparametric Model of Term Structure Dynamics

and the Market Price of Interest Rate Risk. Journal of Finance 52, 1973-

2002.

60. Schwartz, E., 1997. The Stochastic Behavior of Commodity Prices: Im-

plications for Valuation and Hedging. Journal of Finance 52, 923-973.

61. Stein, J., 1989. Overreaction in the options market. Journal of Finance

44, 1011-1023.

62. Whaley, R., 1982, Valuation of American calls on dividend-paying stocks,

Journal of Financial Economics 10, 29-58.

194

Vita

James Stephen Doran was born in London, England on 27 August 1975,

the son of Charles J. Doran and Elaine M. Doran. He received the Bachelor of

Arts degree in Economics from Emory University in 1997. At Emory, he was

recognized as 2nd-team Academic All-America in Soccer in 1997. Subsequent

to graduation, he applied to the University of Texas at Austin for enrollment

in their finance program. He was accepted and started graduate studies in

August, 1998. Starting in August 2004, he will begin as Assistant Professor

at Florida State University.

Permanent address: 2000 Cullen Ave #15Austin, Texas 78757

This dissertation was typeset with LATEX† by the author.

†LATEX is a document preparation system developed by Leslie Lamport as a specialversion of Donald Knuth’s TEX Program.

195