Lecture Notes(Financial Economics)

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    Financial Economics

    Lecture Notes

    Won Joong Kimy

    The materials covered here are mostly from F. Mishkin "The Economics of Money,Banking, and Financial Markets." 8th ed., and J. Hull "Fundamentals of Futures andOptions Markets." 6th ed.. Students are required to read through the textbook in additionto these lecture notes. These notes are preliminary and are not to be quoted or cited.

    yAssistant Professor. Department of Economics, Kangwon National University. Email:[email protected].

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    Contents

    I Introduction 3

    1 Why Study Money, Banking, and Financial Markets? (M. 1) 3

    2 Introduction to Derivatives Markets (H. 1) 9

    3 An Overview of the Financial System (M. 2) 16

    4 What Is Money? (M. 3) 25

    II Financial Markets 27

    5 Understanding Interest Rates (M. 4) 27

    6 The Behavior of Interest Rates (M. 5) 34

    7 The Risk and Term Structure of Interest Rates (M. 6) 43

    8 The Stock Market, the Theory of Rational Expectations, and the

    Ecient Market Hypothesis (M. 7) 49

    9 Capital Asset Pricing and Arbitrage Pricing Theory (BKM 7.) 55

    III Futures and Options Markets 63

    10 Mechanics of Futures Markets (H.2) 63

    11 Hedging Strategies Using Futures (H. 3) 68

    12 Determination of Forward and Futures Prices (H. 5) 75

    13 Swaps (H. 7) 80

    14 Credit Derivatives (H. 21) 88

    15 Mechanics of Options Markets (H. 8) 93

    16 Trading Strategies Involving Options (H. 10) 98

    17 Introduction to Binomial Trees (H. 11) 105

    1

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    18 Valuing Stock Options:The Black-Scholes Model (H. 12) 114

    19 The Greek Letters (H. 15) 119

    IV International Finance and Monetary Policy 124

    20 The Foreign Exchange Market (M. 17) 124

    21 The International Financial System (M. 18) 129

    2

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    Part I

    Introduction

    1 Why Study Money, Banking, and Financial Markets?

    (M. 1)

    Why Study Money, Banking, and Financial Markets

    To examine how nancial markets such as bond, stock and foreign ex-

    change markets work

    To examine how nancial institutions such as banks and insurance com-

    panies work

    To examine the role of money in the economy

    Financial Markets

    Markets in which funds are transferred from people who have an excess

    of available funds to people who have a shortage of funds

    The Bond Market and Interest Rates

    A security (nancial instrument) is a claim on the issuers future income

    or assets

    A bond is a debt security that promises to make payments periodically

    for a specied period of time

    An interest rate is the cost of borrowing or the price paid for the rental

    of funds

    Interest Rates on Selected Bonds (01.108.6). Bank of Korea (BOK)

    3

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    The Stock Market

    Common stock represents a share of ownership in a corporation

    A share of stock is a claim on the earnings and assets of the corporation

    Monthly Average Stock Prices (93.108.6). BOK

    The Foreign Exchange Market

    The foreign exchange market is where funds are converted from one cur-

    rency into another

    The foreign exchange rate is the price of one currency in terms of another

    currency

    The foreign exchange market determines the foreign exchange rate

    Monthly average exchange rate (KRW/Foreign). BOK

    Money and Business Cycles

    Evidence suggests that money plays an important role in generating busi-

    ness cycles

    Recessions (unemployment) and booms (ination) aect all of us

    4

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    Monetary Theory ties changes in the money supply to changes in aggre-

    gate economic activity and the price level

    Money and Ination

    The aggregate price level is the average price of goods and services in an

    economy

    A continual rise in the price level (ination) aects all economic players

    Data shows a connection between the money supply and the price level

    Aggregate Price Level and Money Supply in Korea

    5

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    Money and Interest Rates

    Interest rates are the price of money

    Monetary and Fiscal Policy

    Monetary policy is the management of the money supply and interest

    rates

    Conducted in Korea by the Bank of Korea (BOK)

    Fiscal policy is government spending and taxation

    Budget decit is the excess of expenditures over revenues for a particular

    year

    Budget surplus is the excess of revenues over expenditures for a particular

    year

    Any decit must be nanced by borrowing

    How We Will Study Money, Banking, and Financial Markets

    A simplied approach to the demand for assets

    The concept of equilibrium

    Basic supply and demand to explain behavior in nancial markets

    The search for prots

    An approach to nancial structure based on transaction costs and asym-

    metric information

    Aggregate supply and demand analysis

    6

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    Appedix to Chapter 1: Dening Aggregate Output, Income,

    the Price Level, and the Ination Rate

    Aggregate Output and Aggregate Income

    Aggregate Output

    Gross Domestic Product (GDP) = market value of all nal goods and

    services produced in the domestic economy during a particular year

    Aggregate Income

    Total income of the factors of production (land, capital, labor) during a

    particular year

    Distinction Between Nominal and Real

    Nominal = values measured using current prices

    Real = quantities measured with constant prices

    Real vs. nominal wages, real vs. nominal GDP

    An example:

    Prices and Quantities in 2000 and 2004

    Quantities of Prices of Quantities of Prices of

    pizzas pizzas calzones calzones

    2000 10 $10 15 $5

    2004 20 $12 30 $6

    Nominal GDP

    2000 : (10)($10) + (15)($5) = $175

    2004 : (20)($12) + (30)($6) = $420

    Real GDP (base year: 2000)

    2000 : (10)($10) + (15)($5) = $175

    2004 : (20)($10) + (30)($5) = $350

    7

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    Aggregate Price Level

    Aggregate Price Level is a measure of average prices in the economy

    One measure of the price level is the GDP deator

    GDP deator =nominal GDP

    real GDP

    Another measure is the Consumer Price Index (CPI)

    The CPI is a measure of the average change over time in the prices paid

    by urban consumers for a market basket of goods and services

    Growth Rates and the Ination Rate

    A growth rate is the percentage change in a variable

    Growth rate(%) =xt xt1

    xt1 100

    GDP growth rate =$9.5 trillion $9 trillion

    $9 trillion 100 = 5:6%

    Ination rate=113 111

    111 100 = 1:8%

    8

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    2 Introduction to Derivatives Markets (H. 1)

    The Nature of Derivatives

    A derivative is an instrument whose value depends on the values of other

    more basic underlying variables

    Examples of Derivatives

    Futures Contracts

    Forward Contracts

    Swaps

    Options

    Ways Derivatives are Used

    To hedge risks

    To speculate (take a view on the future direction of the market)

    To lock in an arbitrage prot

    To change the nature of a liability

    To change the nature of an investment without incurring the costs of

    selling one portfolio and buying another

    Futures Contracts

    A futures contract is an agreement to buy or sell an asset at a certain

    time in the future for a certain price

    By contrast in a spot contract there is an agreement to buy or sell the

    asset immediately (or within a very short period of time)

    Exchanges Trading Futures

    KRX (Korea Exchange)

    Chicago Board of Trade, Chicago Mercantile Exchange

    Euronext, Eurex

    BM&F (Sao Paulo, Brazil) and many more

    Futures Price

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    The futures prices for a particular contract is the price at which you

    agree to buy or sell

    It is determined by supply and demand in the same way as a spot price

    Terminology

    The party that has agreed to buy has a long position

    The party that has agreed to sell has a short position

    Example

    January: an investor enters into a long futures contract on COMEX to

    buy 100 oz of gold @ $600 in April April: the price of gold $615 per oz.

    What is the investors prot?

    Over-the Counter Markets

    The over-the counter market is an important alternative to exchanges

    It is a telephone and computer-linked network of dealers who do not

    physically meet

    Trades are usually between nancial institutions, corporate treasurers,

    and fund managers

    Size of OTC and Exchange Markets

    Forward Contracts

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    Forward contracts are similar to futures except that they trade in the

    over-the-counter market

    Forward contracts are popular on currencies and interest rates

    Options

    A call option is an option to buy a certain asset by a certain date for a

    certain price (the strike price)

    A put option is an option to sell a certain asset by a certain date for a

    certain price (the strike price)

    American vs European Options

    An American option can be exercised at any time during its life

    A European option can be exercised only at maturity

    Options vs Futures/Forwards

    A futures/forward contract gives the holder the obligation to buy or sell

    at a certain price

    An option gives the holder the right to buy or sell at a certain price

    Three Reasons for Trading Derivatives: Hedging, Speculation, and Arbitrage

    Hedge funds trade derivatives for all three reasons

    When a trader has a mandate to use derivatives for hedging or arbitrage,

    but then switches to speculation, large losses can result

    Hedging Examples

    A US company will pay 10 million for imports from Britain in 3 months

    and decides to hedge using a long position in a forward contract

    An investor owns 1,000 Microsoft shares currently worth $28 per share.

    A two-month put with a strike price of $27.50 costs $1. The investor

    decides to hedge by buying 10 contracts

    11

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    Value of Microsoft Shares with and without Hedging

    20,000

    25,000

    30,000

    35,000

    40,000

    20 25 30 35 40

    Stock Price ($)

    Value of

    Holding ($)

    No Hedging

    Hedging

    Speculation Example

    An investor with $2,000 to invest feels that Amazon.coms stock price

    will increase over the next 2 months. The current stock price is $20 and

    the price of a 2-month call option with a strike of $22.50 is $1

    What are the alternative strategies?

    Purchase 100 shares of the stock

    Options like futures requires only a small amount of cash to be deposited

    by the speculator in what is termed a margin account

    The futures and options market allows speculator to obtain leverage

    Arbitrage Example

    Arbitrage involves locking in a riskless prot by simultaneously entering

    into transactions in two or more markets

    A stock price is quoted as 100 in London and $182 in New York The current exchange rate is 1.8500

    What is the arbitrage opportunity with 100 shares of the stocks (assum-

    ing zero transaction cost)?

    Buys 100 shares in New York and sells the shares in London Converts the sale proceeds from pound to dollars This leads to a prot of

    [$185 $182] 100 = $300

    12

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    Gold: An Arbitrage Opportunity?

    Suppose that:

    The spot price of gold is US$600 The quoted 1-year futures price of gold is US$650 The 1-year US$ interest rate is 5% per annum No income or storage costs for gold

    Is there an arbitrage opportunity?

    The Futures Price of Gold

    If the spot price of gold is S and the futures price is for a contractdeliverable in T years is F, then

    F = S(1 + r)T

    where r is the 1-year (domestic currency) risk-free rate of interest.

    In our examples, S = 600, T = 1, and r = 0:05 so that

    F = 600(1 + 0:05) = 630

    Oil: An Arbitrage Opportunity?

    Suppose that:

    The spot price of oil is US$70 The quoted 1-year futures price of oil is US$80 The 1-year US$ interest rate is 5% per annum

    The storage costs of oil are 2% per annum

    Is there an arbitrage opportunity?

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    3 An Overview of the Financial System (M. 2)

    Function of Financial Markets

    Perform the essential function of channeling funds from economic players

    that have saved surplus funds to those that have a shortage of funds

    Promotes economic eciency by producing an ecient allocation of cap-

    ital, which increases production

    Directly improve the well-being of consumers by allowing them to time

    purchases better

    Structure of Financial Markets

    Debt and Equity Markets

    Debt: bond, mortgage In terms of maturity: short-term debt (less than a year), long-

    term debt (ten years or longer)

    Equity: residual claim Primary and Secondary Markets

    Investment Banks underwrite securities in primary markets Brokers and dealers work in secondary markets

    Brokers: match buyers with sellers of securities Dealers: link buyers and sellers by buying and selling securities

    at stated prices

    Exchanges and Over-the-Counter (OTC) Markets

    16

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    Money and Capital Markets

    Money markets deal in short-term debt instruments

    Capital markets deal in longer-term debt and equity instruments

    17

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    Internationalization of Financial Markets

    Foreign Bondssold in a foreign country and denominated in that coun-

    trys currency Eurobondbond denominated in a currency other than that of the coun-

    try in which it is sold

    Eurocurrenciesforeign currencies deposited in banks outside the home

    country

    EurodollarsU.S. dollars deposited in foreign banks outside the U.S.or in foreign branches of U.S. banks

    World Stock Markets

    Function of Financial Intermediaries: Indirect Finance

    Lower transaction costs

    Economies of scale Liquidity services

    Reduce Risk

    Risk Sharing (Asset Transformation) Diversication

    Asymmetric Information

    Adverse Selection (before the transaction) more likely to select riskyborrower

    Moral Hazard (after the transaction) less likely borrower will repayloan

    19

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    Regulation of the Financial System

    To increase the information available to investors:

    Reduce adverse selection and moral hazard problems Reduce insider trading

    To ensure the soundness of nancial intermediaries:

    Restrictions on entry Disclosure Restrictions on Assets and Activities Deposit Insurance Limits on Competition Restrictions on Interest Rates

    23

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    4 What Is Money? (M. 3)

    Meaning of Money

    Money (money supply) anything that is generally accepted in payment

    for goods or services or in the repayment of debts; a stock concept

    Wealth the total collection of pieces of property that serve to store

    value

    Income ow of earnings per unit of time

    Functions of Money

    Medium of Exchange promotes economic eciency by minimizing thetime spent in exchanging goods and services

    Must be easily standardized Must be widely accepted Must be divisible Must be easy to carry Must not deteriorate quickly

    Unit of Account used to measure value in the economy Store of Value used to save purchasing power; most liquid of all assets

    but loses value during ination

    Evolution of the Payments System

    Commodity Money

    Money made up of precious metals or another valuable commodity

    Fiat Money

    Currency decreed by government as legal tender (meaning that legallyit must be accepted as payment for debts) but not convertible into

    coins or precious metal

    Checks

    Electronic Payment

    E-Money

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    How Reliable are the Money Data?

    Revisions are issued because:

    Small depository institutions report infrequently Adjustments must be made for seasonal variation

    We probably should not pay much attention to short-run movements in

    the money supply numbers, but should be concerned only with longer-

    run movements

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    Part II

    Financial Markets

    5 Understanding Interest Rates (M. 4)

    Present Value

    A dollar paid to you one year from now is less valuable than a dollar

    paid to you today

    Discounting the Future

    Let i = 0:1.

    In one year $100(1 + 0:1) = $110. In two years $110(1 + 0:1) = $121or 100 (1 + 0:1)2

    In n years, the present value of$100 is equal to $100(1 + i)n. Likewise,the future value of $100 in n years is equal to $100

    (1+i)n(< $100) today.

    Simple Present Value

    PV = todays (present) value

    CF = future cash ow (payment) (in n years)

    i = interest rate

    P V =CF

    (1 + i)n

    In 1626, Manhattan was sold by the Indians to the Dutch at $24 dollars

    Example 1 If we assume that interest rate is 10% and has not been changed

    over time, then $24 is worth (in 2008):

    $24 (1:10)20041626 = $24 (1:10)382 ' $155; 674; 318; 134; 231; 000!!

    Four Types of Credit Market Instruments

    Simple Loan

    Fixed Payment Loan

    Coupon Bond

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    Discount Bond

    Yield to Maturity

    The interest rate that equates the present value of cash ow payments

    received from a debt instrument with its value today

    Simple Loan Yield to Maturity

    PV = amount borrowed = $100

    CF = cash ow in one year = $110

    n = number of years = 1

    $100 =$110

    (1 + i)1) (1 + i) = 110

    100= 1:1 ) i = 0:1 = 10%

    For simple loans, the simple interest rate equals the yield to maturity

    Fixed Payment Loan Yield to Maturity

    The same cash ow every period throughout the life of the loan

    LV = loan value

    FP = xed yearly payment (assuming FP is paid from the next year)

    n= years to maturity

    LV =F P

    1 + i+

    F P

    (1 + i)2+

    F P

    (1 + i)3+ + F P

    (1 + i)n

    Coupon Bond Yield to Maturity

    Using the same strategy used for the xed-payment loan P = price of coupon bond C = yearly coupon payment (assuming C is paid from the next year) F = face value of the bond n = years to maturity n= number of years until maturity

    P =C

    1 + i

    +C

    (1 + i)

    2 +C

    (1 + i)

    3 +

    +

    C+ F

    (1 + i)

    n

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    When the coupon bond is priced at its face value, the yield to maturity

    equals the coupon rate

    The price of a coupon bond and the yield to maturity are negatively

    related

    The yield to maturity is greater than the coupon rate when the bond

    price is below its face value

    Consol or Perpetuity

    A bond with no maturity date that does not repay principal but pays

    xed coupon payments forever

    Remark 2 (Math Review) Let

    Sn = a + ar1 + ar2 + ar3 + + arn1| {z }

    total number of summation = n

    (1)

    rSn = 0 + ar1 + ar2 + ar3 + + arn1 + arn: (2)

    Subtract (2) from (1) ((2) (1))to get

    (1 r) Sn = a (1 rn) ) Sn = a (1 rn)

    (1 r) (3)

    If jrj < 1, then limn!1 rn = 0, and we have

    limn!1

    Sn =a

    (1 r)

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    The price of console is calculated as

    Pc =C

    (1 + ic)+

    C

    (1 + ic)2 + +

    C

    (1 + ic)1

    =

    az }| {C

    1 + ic0BB@1 11 + ic| {z }

    r

    1CCA

    =C

    1+ic1+ic11+ic

    =C

    ic

    where Pc is the price of console, C is the yearly interest payment, ic is

    the yield to maturity.

    Discount Bond - Yield to Maturity

    For any one year discount bond

    P =F

    (1 + i)1! (1 + i) = F

    P! i = F P

    P

    where F is the face value of the discount bond, P is the current price of

    the discount bond

    The yield to maturity equals the increase in price over the year divided

    by the initial price. As with a coupon bond, the yield to the maturity is

    negatively related to the current bond price

    Yield on a Discount Basis

    Less accurate but less dicult to claculate

    idb =

    F

    P

    P 360

    days to maturityidb = yield on a discount basis

    F= face value of the Treasury bill (discount bond)

    P = purchase price of the discount bond

    Uses the percentage gain on the face value

    Puts the yield on a annual basis using 360 instead of 365 days

    Always understates the yields to maturity (relative to compounding

    method)

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    The understatement becomes more severe the longer the maturity

    Following the Financial News: Bond Prices and Interest Rates

    Colons in bid-and-asked quotes represent 32nds; 101:01 means 101 1/32

    Net changes in quotes in hundredths, quoted on terms of a rate of dis-

    count

    Rate of Return

    The payment to the owner plus the change in value expressed as a fraction

    of the purchase price

    Example 3 (One period case) Let

    Pt =C

    (1 + RR)+

    Pt+1(1 + RR)

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    Multiply both sides by (1+RR)Pt

    to get

    (1 + RR) =C

    Pt+

    Pt+1Pt

    ! RR = CPt

    +Pt+1 Pt

    PtRR = return from holding bond from t to t + 1

    Pt (Pt+1) = price of bond at time t (t + 1)

    C= coupon paymentC

    Pt= current yield (= ic)

    Pt+1 PtPt

    = rate of capital gain

    Rate of Return and Interest Rates (yield to maturity)

    The return equals the yield to maturity only if the holding period equals

    the time to maturity

    A rise in interest rates is associated with a fall in bond prices, resulting

    in a capital loss if time to maturity is longer than the holding period

    The more distant a bonds maturity, the greater the size of the percentage

    price change associated with an interest-rate change

    The more distant a bonds maturity, the lower the rate of return the

    occurs as a result of an increase in the interest rate

    Even if a bond has a substantial initial interest rate, its return can be

    negative if interest rates rise

    Interest-Rate Risk

    Prices and returns for long-term bonds are more volatile than those for

    shorter-term bonds

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    There is no interest-rate risk for any bond whose time to maturity matches

    the holding period

    Real and Nominal Interest Rates Nominal interest rate makes no allowance for ination

    Real interest rate is adjusted for changes in price level so it more accu-

    rately reects the cost of borrowing

    Ex ante real interest rate is adjusted for expected changes in the price

    level

    Ex post real interest rate is adjusted for actual changes in the price level

    Fisher Equation

    When the real interest rate is low, there are greater incentives to borrow

    and fewer incentives to lend

    The real interest rate is a better indicator of the incentives to borrow

    and lend

    i = r + e

    i = nominal interest rate

    r = real interest rate

    e = expected ination rate

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    Fisher-Eect

    The tendency for nominal interest rates to be high when ination is high

    and low when ination is low

    6 The Behavior of Interest Rates (M. 5)

    Determining the Quantity Demanded of an Asset

    Wealth the total resources owned by the individual, including all assets

    Expected Return the return expected over the next period on one asset

    relative to alternative assets

    Risk the degree of uncertainty associated with the return on one assetrelative to alternative assets

    Liquidity the ease and speed with which an asset can be turned into

    cash relative to alternative assets

    Theory of Asset Demand

    Holding all other factors constant (ceteris paribus):

    The quantity demanded of an asset is positively related to wealth The quantity demanded of an asset is positively related to its ex-

    pected return relative to alternative assets

    The quantity demanded of an asset is negatively related to the riskof its returns relative to alternative assets

    The quantity demanded of an asset is positively related to its liquid-ity relative to alternative assets

    Supply and Demand for Bonds At lower prices (higher interest rates), ceteris paribus, the quantity de-

    manded of bonds is higher an inverse relationship

    At lower prices (higher interest rates), ceteris paribus, the quantity sup-

    plied of bonds is lower a positive relationship

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    Market Equilibrium

    Occurs when the amount that people are willing to buy (demand) equals

    the amount that people are willing to sell (supply) at a given price

    Shifts in the Demand for Bonds

    Wealth in an expansion with growing wealth, the demand curve forbonds shifts to the right

    Expected Returns higher expected interest rates in the future lower

    the expected return for long-term bonds, shifting the demand curve to

    the left

    Expected Ination an increase in the expected rate of inations lowers

    the expected return for bonds, causing the demand curve to shift to the

    left

    Risk an increase in the riskiness of bonds causes the demand curve to

    shift to the left

    Liquidity increased liquidity of bonds results in the demand curve shift-

    ing right

    Shifts in the Supply of Bonds

    Expected protability of investment opportunities in an expansion, the

    supply curve shifts to the right

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    Expected ination an increase in expected ination shifts the supply

    curve for bonds to the right

    Government budget increased budget decits shift the supply curve to

    the right

    The Fisher Eect: the tendency for nominal interest rates to be high whenination is high and low when ination is low

    When expected ination rises, the expected return on bonds relative to

    real assets falls

    As a result, the demand for bonds falls The real cost of borrowing declines

    The supply curve shifts to the right

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    Changes in the Interest Rate Due to a Business Cycle Expansion

    Depending on whether the supply curve shifts more than the demand

    curve, or vice versa, the new equilibrium interest rate can either rise orfall

    The Liquidity Preference Framework

    Keynesian model that determines the equilibrium interest rate in terms

    of the supply and the demand for money

    There are two main categories of assets that people use to store their

    wealth: money and bonds

    Total wealth of the economy

    Bs + Ms = Bd + Md

    !Bs

    Bd = Md

    Ms

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    If the market for money is in equilibrium

    Ms = Md

    , then the bond

    market is also in equilibrium

    Bs = Bd

    Shifts in the Demand for Money

    Income Eect a higher level of income causes the demand for money at

    each interest rate to increase and the demand curve to shift to the right

    Price-Level Eect a rise in the price level causes the demand for moneyat each interest rate to increase and the demand curve to shift to the

    right

    Shifts in the Supply of Money

    Assume that the supply of money is controlled by the central bank

    An increase in the money supply engineered by the Federal Reserve will

    shift the supply curve for money to the right

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    Everything Else Remaining Equal?

    Liquidity preference framework leads to the conclusion that an increasein the money supply will lower interest rates the liquidity eect

    Income eect of an increase in the money supply nds interest rates rising

    Because increasing the money supply is an expansionary inuenceon the economy, it should raise national income and wealth

    Then interest rates will rise due to a shift upward in money demand Price-Level eect predicts an increase in the money supply leads to a rise

    in interest rates in response to the rise in the price level

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    A rise in price level force people to have more money causing themoney demand curve to shift upward. It will cause the interest rate

    to rise

    Expected-Ination eect shows an increase in interest rates because an

    increase in the money supply may lead people to expect a higher price

    level in the future

    An increase in the money supply may lead people to expect a higherprice level in the futureand hence the expected ination rate will

    be higher

    Then this increase in ination will lead to a higher level of interestrates

    M

    DM

    0

    SM

    0i

    1i

    1

    SM

    (A) Liquidity

    Effect

    i

    M

    0

    DM

    0

    SM

    0i

    1i

    1

    SM

    (B) Income Effect,

    Price-level Effect

    i

    1

    DM

    (1)

    (2)

    Price-Level Eect and Expected-Ination Eect

    A one time increase in the money supply will cause prices to rise to a

    permanently higher level by the end of the year. The interest rate will

    rise via the increased prices

    Price-level eect remains even after prices have stopped rising.

    A rising price level will raise interest rates because people will expect

    ination to be higher over the course of the year. When the price level

    stops rising, expectations of ination will return to zero

    Expected-ination eect persists only as long as the price level continues

    to rise

    Does a Higher Rate of Growth of the Money Supply Lower Interest rates?

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    Liquidity eect indicates that a higher rate of money growth will cause

    a decline in interest rates

    In contrast, the income, price-level, and expected-ination eects indi-

    cate that interest rates will rise when money growth is higher

    Which of these eects are largest, and how quickly do the take eects?

    Generally, the liquidity eect from the greater money growth takeseect immediately because the rising money supply leads to an im-

    mediate decline in the equilibrium interest rate

    The income and price-level eects take time to work The expected-ination eect can be slow or fast, depending on whether

    people adjust their expectations of ination slowly or quickly whenthe money growth rate is increased

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    7 The Risk and Term Structure of Interest Rates (M. 6)

    Risk Structure of Interest Rates

    Default risk occurs when the issuer of the bond is unable or unwilling

    to make interest payments or pay o the face value

    U.S. T-bonds are considered default free Risk premium the spread between the interest rates on bonds with

    default risk and the interest rates on T-bonds

    Liquidity the ease with which an asset can be converted into cash

    Income tax considerations

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    Term Structure of Interest Rates

    Bonds with identical risk, liquidity, and tax characteristics may have

    dierent interest rates because the time remaining to maturity is dierent

    Yield curve a plot of the yield on bonds with diering terms to maturity

    but the same risk, liquidity and tax considerations

    Upward-sloping: long-term rates are above short-term rates

    Flat" short- and long-term rates are the same Inverted: long-term rates are below short-term rates

    Facts that Theory of the Term Structure of Interest Rates Must Explain

    Interest rates on bonds of dierent maturities move together over time

    When short-term interest rates are low, yield curves are more likely to

    have an upward slope; when short-term rates are high, yield curves are

    more likely to slope downward and be inverted

    Yield curves almost always slope upward

    Three Theories to Explain the Three Facts

    Expectations theory explains the rst two facts but not the third

    Segmented markets theory explains fact three but not the rst two

    Liquidity premium theory combines the two theories to explain all three

    facts

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    Expectations Theory

    The interest rate on a long-term bond will equal an average of the short-

    term interest rates that people expect to occur over the life of the long-term bond

    Buyers of bonds do not prefer bonds of one maturity over another; they

    will not hold any quantity of a bond if its expected return is less than

    that of another bond with a dierent maturity

    Bonds like these are said to be perfect substitutes

    Expectations Theory Example

    Let the current rate on one-year bond be 6%

    You expect the interest rate on a one-year bond to be 8% next year

    Then the expected return for buying two one-year bonds averages (6%

    + 8%)/2 = 7%

    The interest rate on a two-year bond must be 7% for you to be willing

    to purchase it

    Expectations Theory In General

    Let it is todays interest rate on a one-period bond, i2t is todays interest

    on the two-period bond, iet+1 is interest rate on a one-period bond for

    next period

    Expected return over the two periods from investing $1 in the two-period

    bond and holding it for the two periods is

    (1 + i2t) (1 + i2t) 1 = 1 + 2i2t + (i2t)2 1 = 2i2t + (i2t)2

    Since (i2t)2 is small, the expected return for holding the two-period bonds

    for two periods is 2i2t

    If two one-period bonds are bought with $1 investment, the expected

    return is

    (1 + it)

    1 + iet+1 1 = 1 + it + iet+1 + (it) iet+1 1

    = it + iet+1 + (it)

    iet+1

    Since (it)

    iet+1

    is small, simplifying we get it + i

    et+1

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    Both bonds will be held only if the expected returns are equal

    2i2t = it + iet+1 ! i2t =

    it + iet+1

    2

    The two-period rate must equal the average of the two one-period rates

    For bonds with longer maturities

    int =it + i

    et+1 + i

    et+2 + + iet+(n1)

    n

    The n-period interest rate equal the average of the one-period interest

    expected to occur over the n-period life of the bond

    Expectations Theory

    Explains why the term structure of interest rates changes at dierent

    times

    Explains why interest rates on bonds with dierent maturities move to-

    gether over time (fact 1)

    Explains why yield curves tend to slope up when short-term rates are

    low and slope down when short-term rates are high (fact 2)

    Cannot explain why yield curves usually slope upward (fact 3)

    Segmented Markets Theory

    Bonds of dierent maturities are not substitutes at all

    The interest rate for each bond with a dierent maturity is determined

    by the demand for and supply of that bond

    Investors have preferences for bonds of one maturity over another

    If investors have short desired holding periods and generally prefer bonds

    with shorter maturities that have less interest-rate risk, then this explains

    why yield curves usually slope upward (fact 3)

    Liquidity Premium & Preferred Habitat Theories

    The interest rate on a long-term bond will equal an average of short-term

    interest rates expected to occur over the life of the long-term bond plus

    a liquidity premium that responds to supply and demand conditions for

    that bond

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    Bonds of dierent maturities are substitutes but not perfect substitutes

    Liquidity Premium Theory

    int =it + iet+1 + iet+2 + + iet+(n1)

    n+ lnt

    where lnt is the liquidity premium for the n-period bond at time t. lnt is

    always positive and rise with term to maturity

    Preferred Habitat Theory

    Investors have a preference for bonds of one maturity over another

    They will be willing to buy bonds of dierent maturities only if they earna somewhat higher expected return

    Investors are likely to prefer short-term bonds over longer-term bonds

    Liquidity Premium and Preferred Habitat Theories, Explanation of the Facts

    Interest rates on dierent maturity bonds move together over time; ex-plained by the rst term in the equation

    Yield curves tend to slope upward when short-term rates are low and to

    be inverted when short-term rates are high; explained by the liquidity

    premium term in the rst case and by a low expected average in the

    second case

    Yield curves typically slope upward; explained by a larger liquidity pre-

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    mium as the term to maturity lengthens

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    Proof. Write the genearalized stock valuation equation as

    P0 =D1

    (1 + ke)1 +

    D2

    (1 + ke)2 + +

    Dn1(1 + ke)

    n1

    =D0 (1 + g)

    1

    (1 + ke)1 +

    D0 (1 + g)2

    (1 + ke)2 + +

    D0 (1 + g)n1

    (1 + ke)n1

    = D0

    "1 + g

    1 + ke

    +

    1 + g

    1 + ke

    2+ +

    1 + g

    1 + ke

    n1#(1)

    Mitiply both sides of (1) by

    1+g1+ke

    to get

    1 + g1 + keP0 = D0 "0 + 1 + g1 + ke2

    + 1 + g1 + ke3

    + + 1 + g1 + ken1

    + 1 + g1 + ken

    #(2)

    Subtract (2) from (1) to get

    P0

    1 + g

    1 + ke

    P0 = D0

    1 + g

    1 + ke

    1 + g

    1 + ke

    n

    P0

    ke g1 + ke

    = D0

    1 + g

    1 + ke

    1 + g

    1 + ke

    n

    If n !1, 1+g1+ken ! 0 (because ke > g), and we haveP0

    ke g1 + ke

    = D0

    1 + g

    1 + ke

    ! P0 = D0 (1 + g)

    ke g =D1

    ke g

    How the Market Sets Prices

    The price is set by the buyer willing to pay the highest price

    The market price will be set by the buyer who can take best advantage

    of the asset

    Superior information about an asset can increase its value by reducing

    its risk

    Adaptive vs. Rational Expectation

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    Rational expectation implies

    P= P +

    E(P) = Pe = P + E() = P:

    On the other hand, adaptive expectation implies

    Pt =1Xi=1

    iPti + t; 0 < < 1

    E(Pt) = Pet =

    1Xi=1

    iPti:

    Theory of Rational Expectations

    Expectations will be identical to optimal forecasts using all available

    information

    Even though a rational expectation equals the optimal forecast using

    all available information, a prediction based on it may not always be

    perfectly accurate

    It takes too much eort to make the expectation the best guess

    possible

    Best guess will not be accurate because predictor is unaware of somerelevant information

    Formal Statement of the Theory of Rational Expectations

    Xe = Xof

    where Xe is the expectation of the variable that is being forecast, Xof is the

    optimal forecast using all available information

    Implications

    If there is a change in the way a variable moves, the way in which ex-

    pectations of the variable are formed will change as well

    The forecast errors of expectations will, on average, be zero and cannot

    be predicted ahead of time

    Ecient Markets Application of Rational Expectations

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    Recall that the rate of return from hodling a security equals the sum of

    the capital gain on security, plus any cash payment divided by the initial

    purchase price of the security

    R =Pt+1 Pt + C

    Pt

    where Pt (Pt+1) is the price of the security at time t (t + 1), the beginning

    (end) of the holding period, C is the cas payment (coupon or dividend)

    made during the holding period

    At the beginning of the holding period, we know Pt and C. Pt+1 is

    unknown and we must form an expectation of it. The expected return

    then isRe =

    Pet+1 Pt + CPt

    Expectations of future prices are equal to optimal forecasts using all

    currently available information so

    Pet+1 = Poft+1 ) Re = Rof

    Supply and demand analysis states Re will be equal the equilibrium

    return R soRof = R

    Ecient Markets

    Current prices in a nancial market will be set so that the optimal fore-

    cast of a securitys return using all available information equals the se-

    curitys equilibrium return

    In an ecient market, a securitys price fully reects all available infor-

    mation

    Rationale

    Rof> R ) Pt ") Rof #; Rof < R ) Pt #) Rof "until

    Rof= R

    In an ecient market, all unexploited prot opportunities will be eliminated

    Evidence in Favor of Market Eciency

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    Having performed well in the past does not indicate that an investment

    advisor or a mutual fund will perform well in the future

    If information is already publicly available, a positive announcement does

    not, on average, cause stock prices to rise

    Stock prices follow a random walk

    Future changes in stock prices should, for all practical purposes, beunpredictatble. Formally,

    pt =pt1 + ut or pt pt1 = pt = utut i:i:d N(0; 1)

    The change in stock price is randomly determined.

    Technical analysis cannot successfully predict changes in stock prices

    Evidence Against Market Eciency

    Small-rm eect

    Small rms earned abnormally high returns over long periods oftime, even when the greater risk for these rms have been taken into

    account January Eect

    Abnormal price rise from December to January that is predictableand hence inconsistent with random-walk behavior

    Market Overreaction

    Excessive Volatility

    Mean Reversion

    New information is not always immediately incorporated into stock prices

    Application Investing in the Stock Market

    Recommendations from investment advisors cannot help us outperform

    the market

    A hot tip is probably information already contained in the price of the

    stock

    Stock prices respond to announcements only when the information is new

    and unexpected

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    A buy and hold strategy is the most sensible strategy for the small

    investor

    Behavioral Finance The lack of short selling (causing over-priced stocks) may be explained

    by loss aversion

    The large trading volume may be explained by investor overcondence

    Stock market bubbles may be explained by overcondence and social

    contagion

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    9 Capital Asset Pricing and Arbitrage Pricing Theory (BKM

    7.)

    Capital Asset Pricing Model (CAPM) Equilibrium model that underlies all modern nancial theory

    Derived using principles of diversication with simplied assumptions

    Markowitz, Sharpe, Lintner and Mossin are researchers credited with its

    development

    Assumptions

    Individual investors are price takers

    Single-period investment horizon

    Investments are limited to traded nancial assets

    No taxes, and transaction costs (frictionless market)

    Information is costless and available to all investors

    Investors are rational mean-variance optimizers

    Homogeneous expectations

    Resulting Equilibrium Conditions

    All investors will hold the same portfolio for risky assets market port-

    folio

    Market portfolio contains all securities and the proportion of each secu-

    rity is its market value as a percentage of total market value

    Risk premium on the market depends on the average risk aversion of all

    market participants

    Risk premium on an individual security is a function of its covariance

    with the market

    CAPMs Expected Return-Beta Relationship

    E(ri) rf = i [E(rM) rf]

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    where

    E(ri) : expected return on stock i

    rf : return from a risk-free asset

    E(rM) : expected return on market portfolio

    i : sensitivity of stock i on market risk premium

    The Ecient Frontier and the Capital Market Line

    Ecient Frontier: Graph representing a set of portfolios that maximizes

    expected return at each level of portfolio risk.

    Capital Allocation Line (CAL): Plot of risk-return combinations avail-able by varying portfolio allocation between a risk-free asset and a risky

    portfolio.

    Capital Market Line (CML): The capital allocation line using the market

    index portfolio as the risky asset.

    Aggressive

    Portfolio

    Market

    Portfolio

    Conservative

    Portfolio

    M

    ( )rE

    Efficient

    Frontier

    rf

    ( )rME

    ( )

    Capital Market

    Line CML

    Expected Return and Risk on Individual Securities

    If all investors use identical mean-variance analysis (assumption 5), apply it to the sameuniverse of securities (assumption 3), with an identical time horizon (assumption 2), use the samesecurity analysis (assumption 6), and experience identical tax consequences (assumption 4), theyall must arrive at the same determination of the optimal risky portfolio. That is, they all deriveidentical ecient frontiers and nd the same tangency portfolio for the capital allocation line(CAL) from T-bills (the risk-free rate, with zero standard deviation) to that frontier. Because

    each investor uses the market portfolio for the optimal risky portfolio, the CAL in this case iscalled the capital market line, or CML

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    The risk premium on individual securities is a function of the individual

    securitys contribution to the risk of the market portfolio

    Individual securitys risk premium is a function of the covariance of re-

    turns with the assets that make up the market portfolio

    The Security Market Line and Positive Alpha Stock

    Security Market Line (SML): Graphical representation of the expected

    returnbeta relationship of the CAPM

    Alpha (): The abnormal rate of return on a security in excess of what

    would be predicted by an equilibrium model such as the CAPM.

    E(r) rf= [E(rM) rf]E(r) = rf + [E(rM) rf]| {z }

    Slope

    Stock 4

    Stock 3

    Stock 2

    MarketPortfolio

    Stock 1

    f

    100

    Security MarketLine (SML)

    Stock 1

    rf

    ( )rME

    Stock 2

    Stock 3

    Stock 4

    Capital MarketLine (CML)

    ( )rE

    = 0 rf

    = 12

    = 1

    MarketPortfolio

    ( )rE

    ( )rME

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    SML Relationships

    =cov (ri; rM)

    MSlope SM L = E(rM) rf

    = market risk premium

    SM L = rf + [E(rM rf)]

    An example:

    Suppose the return on the market is expected to be 14%, a stock has

    a beta of 1.2, and the T-bill rate is 6%. The SML would predict an

    expected return on the stock of

    E(r) = rf + [E(rM) rf] = 0:06 + [0:14 0:06] 1:2 = 0:156 (15:6%)

    If one believes the stock will provide instead a return of 17%, its implied

    alpha would be 1.4%.

    Estimating the Index Model

    The CAPM has two limitations: It relies on the theoretical market port-

    folio, which includes all assets, and it deals with expected as opposed to

    actual returns. To implement the CAPM, we cast it in the form of an

    index model and use realized, not expected, returns

    Using historical data on T-bills, S&P 500 and individual securities Regress risk premiums for individual stocks against the risk premi-

    ums for the S&P 500

    Slope is the beta for the individual stock

    ri rf| {z }excess return on i

    = i + i (rM rf)| {z }excess return on marekt portpolio

    + et

    where where ri is the holding-period return (HPR) on asset i, and

    i and i are the intercept and slope of the line that relates asset

    is realized excess return to the realized excess return of the index.

    The ei measures rm-specic eects during the holding period; it is

    the deviation of security is realized HPR from the regression line,

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    that is, the deviation from the forecast that accounts for the indexs

    HPR.

    Security Characteristic Line (SCL) A plot of a securitys expected excess return over the risk-free rate as a

    function of the excess return on the market.

    Multifactor Models Limitations for CAPM

    Market Portfolio is not directly observable

    Research shows that other factors aect returns

    Fama French Research

    Returns are related to factors other than market returns

    Size

    Book value relative to market value

    Three factor model better describes returns

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    Regression Statistics for the Single-index and FF Three-factor Model

    Arbitrage

    Arises if an investor can construct a zero beta investment portfolio with

    a return greater than the risk-free rate, or

    Arises when an investor can construct a zero-investment portfoliothat will yield a sure prot

    If two portfolios are mispriced, the investor could buy the low-priced

    portfolio and sell the high-priced portfolio

    In ecient markets, protable arbitrage opportunities will quickly dis-appear

    Arbitrage Pricing Theory (Stephen Ross (1976))

    A theory of risk-return relationships derived from no-arbitrage consider-

    ations in large capital markets

    By showing that mispriced portfolios would give rise to arbitrage op-

    portunities, the APT arrives at an expected returnbeta relationship for

    portfolios identical to that of the CAPM

    Security Characteristic Lines

    Figure below illustrates the dierence between a single security with a

    beta of 1.0 and a well-diversied portfolio with the same beta. For the

    portfolio (Panel A), all the returns plot exactly on the security character-

    istic line. There is no dispersion around the line, as in Panel B, because

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    the eects of rm-specic events are eliminated by diversication.

    Mathematical Illustration of APT

    In its simple form, just like the CAPM, the APT posits a single-factor se-

    curity market. Thus, the excess rate of return on each security, Ri (= ri rf),can be represented by

    ri rf = i + i [rM rf] + e

    A well-diversied portfolio has zero rm-specic risk, we can write its

    returns as

    rp rf = p + p [rM rf]

    The only value for alpha that rules out arbitrage opportunities is zero,

    i.e.,

    rp rf = p [rM rf]

    Hence, we arrive at the same expected returnbeta relationship as the

    CAPM without any assumption about either investor preferences or ac-

    cess to the all-inclusive (and elusive) market portfolio.

    APT and CAPM Compared

    APT applies to well diversied portfolios and not necessarily to individ-

    ual stocks

    With APT it is possible for some individual stocks to be mispriced - not

    lie on the SML

    APT is more general in that it gets to an expected return and beta

    relationship without the assumption of the market portfolio

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    APT can be extended to multifactor models

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    maintenance margin is US$1,500/contract (US$3,000 in total)

    Daily Cumulative Margin

    Futures Gain Gain Account MarginPrice (Loss) (Loss) Balance Call

    Day (US$) (US$) (US$) (US$) (US$)

    400.00 4,000

    5-Jun 397.00 (600) (600) 3,400 0. . . . . .. . . . . .. . . . . .

    13-Jun 393.30 (420) (1,340) 2,660 1,340. . . . . .. . . . .. . . . . .

    19-Jun 387.00 (1,140) (2,600) 2,740 1,260. . . . . .. . . . . .. . . . . .

    26-Jun 392.30 260 (1,540) 5,060 0

    +

    = 4,000

    3,000

    +

    = 4,000

    E(ST)),

    the situation is known as contango

    Nowadays, it is also called contango when Ft;T > St Oil market typically shows a contango

    Questions

    When a new trade is completed what are the possible eects on the open

    interest?

    Can the volume of trading in a day be greater than the open interest?

    Regulation of Futures

    Regulation is designed to protect the public interest

    Regulators try to prevent questionable trading practices by either indi-

    viduals on the oor of the exchange or outside groups

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    Accounting & Tax

    It is logical to recognize hedging prots (losses) at the same time as the

    losses (prots) on the item being hedged It is logical to recognize prots and losses from speculation on a mark to

    market basis

    Roughly speaking, this is what the accounting and tax treatment of

    futures in the U.S.and many other countries attempts to achieve

    Forward Contracts

    A forward contract is an OTC agreement to buy or sell an asset at a

    certain time in the future for a certain price

    There is no daily settlement (unless a collateralization agreement requires

    it). At the end of the life of the contract one party buys the asset for

    the agreed price from the other party

    Prot from a Long Forward or Futures Position

    Profit

    Price of Underlying

    at Maturity

    Prot from a Short Forward or Futures PositionProfit

    Price of Underlying

    at Maturity

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    Forward Contracts vs Futures Contracts

    Foreign Exchange Quotes

    Futures exchange rates are quoted as the number of USD per unit of theforeign currency

    Forward exchange rates are quoted in the same way as spot exchange

    rates. This means that GBP, EUR, AUD, and NZD are USD per unit of

    foreign currency. Other currencies (e.g., CAD and JPY) are quoted as

    units of the foreign currency per USD.

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    11 Hedging Strategies Using Futures (H. 3)

    Long & Short Hedges

    A long futures hedge is appropriate when you know you will purchase an

    asset in the future and want to lock in the price

    A short futures hedge is appropriate when you know you will sell an asset

    in the future & want to lock in the price

    Arguments in Favor of Hedging

    Companies should focus on the main business they are in and take steps

    to minimize risks arising from interest rates, exchange rates, and other

    market variables

    Arguments against Hedging

    Shareholders are usually well diversied and can make their own hedging

    decisions

    It may increase risk to hedge when competitors do not

    Explaining a situation where there is a loss on the hedge and a gain on

    the underlying can be dicult

    Convergence of Futures to Spot (Hedge initiated at time t1 and closed out attime t2)

    Basis Risk

    Basis is the dierence between spot & futures

    Basis risk arises because of the uncertainty about the basis when the

    hedge is closed out

    Long Hedge

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    In the future, you must buy some products at the market price

    Suppose that F1 : Initial Futures Price, F2 : Final Futures Price, S2 :

    Final Asset Price

    You hedge the future purchase of an asset by entering into a long futures

    contract

    Cost of Asset = S2 (F2 F1) = F1 + Basis

    An example: It is January 15. A copper fabricator knows it will require

    100,000 pounds of copper on May 15 to meet a certain contract. The

    spot price of copper is 340 cents per pound and the May futures price

    is 320 cents per pound. The fabricator can hedge with the following

    transactions:

    January 15: Take a long position in four May futures on copper (onecontract contains 25,000 pounds of copper)

    May 15: Close out the position Suppose that the price of copper on May 15 proves to be 325 cents

    per pound. Because May is the delivery month for the futures con-

    tract, this should be very close to the futures price. The fabricator

    therefore gains approximately

    100; 000 ($3:25 3:20) = $5; 000

    on the futures contracts. It pays 100; 000$3:25 = $325; 000 for thecopper, making the total cost approximately $325; 000 $5; 000 =$320; 000: (or 320 cents per pound)

    Short Hedge

    In the future, you must sell your product at the market price

    Suppose that F1 : Initial Futures Price, F2 : Final Futures Price, S2 :

    Final Asset Price

    You hedge the future sale of an asset by entering into a short futures

    contract

    Price Realized = S2 + (F1 F2) = F1 + Basis

    An example: It is May 15. An oil producer has negotiated a contract to

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    sell 1 million barrels of crude oil. The price in the sales contract is the

    spot price on August 15.

    Quotes:

    Spot price of crude oil: $60 per barrel August oil futures price: $59 per barrel

    The oil producer can hedge with the following transactions: May 15: Short 1,000 August futures contracts on crude oil (1

    contract = 1,000 barrel)

    August 15: Close out futures position Suppose that the spot price on August 15 proves to be $55 per barrel.

    The company realize $55 million for the oil under its sales contract.Because August is the delivery month for the futures contract, the

    future price on August 15 should be very close to the spot price of

    $55 on that date. The company therefore gains approximately

    $59-$55=$4 per barrel, or $4 million in total from the shortfutures position

    The total amount realized from both the futures position andthe sales contract is therefore approximately $59 per barrel, or

    $59 million in total

    Choice of Contract

    Choose a delivery month that is as close as possible to, but later than,

    the end of the life of the hedge

    When there is no futures contract on the asset being hedged, choose

    the contract whose futures price is most highly correlated with the asset

    price. There are then 2 components to basis

    Dene S2 as the price of the asset underlying the futures contractat time t2

    As before, S2 is the price of the asset being hedged at time t2 By hedging, a company ensures that the price that will be paid (or

    received) for the asset is

    S2 + F1 F2

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    To hedge the risk in a portfolio the number of contracts that should be

    shorted is

    P

    F

    where P is the value of the portfolio, is its beta, and F is the current

    value of one futures (=futures price times contract size)

    Reasons for Hedging an Equity Portfolio

    Desire to be out of the market for a short period of time. (Hedging may

    be cheaper than selling the portfolio and buying it back.)

    Desire to hedge systematic risk (Appropriate when you feel that you have

    picked stocks that will outpeform the market.)

    Example

    Futures price of S&P 500 is 1,000, Size of portfolio is $5 million, Beta of

    portfolio is 1.5, One contract is on $250 times the index

    What position in futures contracts on the S&P 500 is necessary to hedge

    the portfolio?

    N = SF

    F=$250 1; 000 = 250; 000N = 1:5 5; 000; 000

    250; 000= 30 (short)

    Changing Beta

    What position is necessary to reduce the beta of the portfolio to 0.75?

    N = 0:75 5; 000; 000

    250; 000 = 15 (short)

    Therefore, contract should be reduced by 15.

    What position is necessary to increase the beta of the portfolio to 2.0?

    N = 2:0 5; 000; 000250; 000

    = 40 (short)

    Therefore, contract should be increased by 10.

    Rolling The Hedge Forward

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    We can use a series of futures contracts to increase the life of a hedge

    Each time we switch from 1 futures contract to another we incur a type

    of basis risk

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    12 Determination of Forward and Futures Prices (H. 5)

    Consumption vs Investment Assets

    Investment assets are assets held by signicant numbers of people purely

    for investment purposes (Examples: gold, silver)

    Consumption assets are assets held primarily for consumption (Example:

    oil)

    Short Selling

    Short selling involves selling securities you do not own

    Your broker borrows the securities from another client and sells them inthe market in the usual way

    At some stage you must buy the securities back so they can be replaced

    in the account of the client

    You must pay dividends and other benets the owner of the securities

    receives

    Notation

    S0 : Spot price today

    F0 : Futures or forward price today

    T : Time until delivery date

    r : Risk-free interest rate for maturity T

    Gold: An Arbitrage Opportunity?

    Suppose that: The spot price of gold is US$600 The quoted 1-year futures price of gold is US$650 The 1-year US$ interest rate is 5% per annum No income or storage costs for gold

    Is there an arbitrage opportunity?

    The Futures Price of Gold

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    Forward vs Futures Prices

    Forward and futures prices are usually assumed to be the same. When

    interest rates are uncertain they are, in theory, slightly dierent: A strong positive correlation between interest rates and the asset price

    implies the futures price is slightly higher than the forward price

    A strong negative correlation implies the reverse

    Stock Index

    Can be viewed as an investment asset paying a dividend yield

    The futures price and spot price relationship is therefore

    F0 = S0e(rq)T

    where q is the dividend yield on the portfolio represented by the index

    during life of contract

    For the formula to be true it is important that the index represent an

    investment asset

    In other words, changes in the index must correspond to changes in the

    value of a tradable portfolio

    The Nikkei index viewed as a dollar number does not represent an in-

    vestment asset

    Index Arbitrage

    When F0 > S0e(rq)T an arbitrageur buys the stocks underlying the index

    and sells futures

    When F0 < S0e(rq)T an arbitrageur buys futures and shorts or sells the

    stocks underlying the index

    Index arbitrage involves simultaneous trades in futures and many dier-

    ent stocks

    Very often a computer is used to generate the trades

    Occasionally (e.g., on Black Monday) simultaneous trades are not possi-

    ble and the theoretical no-arbitrage relationship between F0 and S0 does

    not hold

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    Futures and Forwards on Currencies

    A foreign currency is analogous to a security providing a dividend yield

    The continuous dividend yield is the foreign risk-free interest rate

    It follows that if rf is the foreign risk-free interest rate

    F0 = S0e(rrf)T

    Why the Relation Must Be True

    1000 units of

    foreign currency

    at time zero

    units of foreign

    currency at time T

    Trfe1000

    dollars at time T

    TrfeF01000

    1000S0 dollars

    at time zero

    dollars at time T

    rTeS01000

    1000 units of

    foreign currency

    at time zero

    units of foreign

    currency at time T

    Trfe1000

    dollars at time T

    TrfeF01000

    1000S0 dollars

    at time zero

    dollars at time T

    rTeS01000

    Futures on Consumption Assets

    F0 S0e(r+u)T

    where u is the storage cost per unit time as a percent of the asset value.

    Alternatively,

    F0 (S0 + U)erT

    where U is the present value of the storage costs.

    The Cost of Carry

    The cost of carry, c, is the storage cost plus the interest costs less the

    income earned

    For an investment asset F0 = S0ecT

    For a consumption asset F0 S0ecT

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    The convenience yield on the consumption asset, y, is dened so that

    F0 = S0e(cy)T

    Futures Prices & Expected Future Spot Prices

    Suppose k is the expected return required by investors on an asset

    We can invest F0erT now to get ST back at maturity of the futures

    contract

    This shows that

    F0 = E(ST)e(rk)T

    If the asset has

    no systematic risk, then k = r and F0 is an unbiased estimate of ST positive systematic risk, then k > r and F0 < E(ST) negative systematic risk, then k < r and F0 > E(ST)

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    13 Swaps (H. 7)

    Nature of Swaps

    A swap is an agreement to exchange cash ows at specied future times

    according to certain specied rules

    An Example of a Plain Vanilla Interest Rate Swap

    An agreement by Microsoft to receive 6-month LIBOR & pay a xed rate

    of 5% per annum every 6 months for 3 years on a notional principal of

    $100 million, and in return Intel agrees to pay Microsoft the six month

    LIBOR rate on the same principal

    Cash Flows to Microsoft

    ---------Millions of Dollars---------

    LIBOR FLOATING FIXED Net

    Date Rate Cash Flow Cash Flow Cash Flow

    Mar.5, 2007 4.2%

    Sept. 5, 2007 4.8% +2.10 2.50 0.40

    Mar.5, 2008 5.3% +2.40 2.50 0.10

    Sept. 5, 2008 5.5% +2.65 2.50 +0.15

    Mar.5, 2009 5.6% +2.75 2.50 +0.25

    Sept. 5, 2009 5.9% +2.80 2.50 +0.30

    Mar.5, 2010 6.4% +2.95 2.50 +0.45

    Typical Uses of an Interest Rate Swap

    Converting a liability from

    xed rate to oating rate oating rate to xed rate

    Converting an investment from

    xed rate to oating rate oating rate to xed rate

    Intel and Microsoft (MS) Transform a Liability

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    When Financial Institution is Involved

    Intel F.I. MS

    LIBOR LIBOR

    4.7%

    5.015%4.985%

    LIBOR-0.2%

    Quotes By a Swap Market Maker

    The average of the bid and oer xed rate is known as the swap rate

    The Comparative Advantage Argument

    AAACorp wants to borrow oating

    BBBCorp wants to borrow xed

    Fixed Floating

    AAACorp 4.00% 6-month LIBOR + 0.30%

    BBBCorp 5.20% 6-month LIBOR + 1.00%

    BBB pays 1.2% more than AAA in xed-rate markets and only 0.7%

    more than AAA in oating-rate markets

    BBB appears to have a comparative advantage in oating-rate mar-kets, whereas AAA appears to have a comparative advantage in

    xed-rate markets

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    This is because the lender can enter into a swap where income from the

    LIBOR loans is exchanged for the 5-year swap rate

    Valuation of an Interest Rate Swap Interest rate swaps can be valued as the dierence between the value of

    a xed-rate bond and the value of a oating-rate bond

    Alternatively, they can be valued as a portfolio of forward rate agree-

    ments (FRAs)

    Valuation in Terms of Bonds

    The xed rate bond is valued in the usual way

    The oating rate bond is valued by noting that it is worth par immedi-

    ately after the next payment date

    Example

    Receive 8% per annum and pay oating semiannually on a principalof $100 million.

    1.25 years to go and next oating payment is $5.1 million

    The LIBOR rates with continuous compounding for 3-month, 9-month, and 15-month maturities are 10%, 10.5%, and 11%

    The 6-month LIBOR rate at the last payment was 10.2% (with semi-annual compounding)

    Time Fixed Floating Disc PV fixed PV f loating

    Bond Bond Factor Bond Bond

    0.25 4 105.1 0.9753 3.901 102.5045

    0.75 4 0.9243 3.697

    1.25 104 0.8715 90.64

    98.238 102.505

    Swap value (long position in a xed-rate bond and a short positionin a oating-rate bond)

    Vswap = Bfix Boat= 98:238 102:505 = 4:267

    Valuation in Terms of FRAs

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    Credit Risk

    A swap is worth zero to a company initially

    At a future time its value is liable to be either positive or negative

    The company has credit risk exposure only when its value is positive

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    14 Credit Derivatives (H. 21)

    Credit Default Swaps (CDS)

    Buyer of the instrument acquires protection from the seller against adefault by a particular company or country (the reference entity)

    Example: Buyer pays a premium of 90 bps per year for $100 millionof 5-year protection against company X

    Premium is known as the credit default spread. It is paid for life of

    contract or until default

    If there is a default, the buyer has the right to sell bonds with a face value

    of $100 million issued by company X for $100 million (Several bonds maybe deliverable)

    CDS Structure

    Default

    Protection

    Buyer, A

    Default

    Protection

    Seller, B

    90 bps per year

    Payoffif there is a default byreference entity=100(1-

    R)

    Recovery rate, R, is the ratio of the value of the bond issued by reference

    entity immediately after default to the face value of the bond

    Attractions of the CDS Market

    Allows credit risks to be traded in the same way as market risks

    Can be used to transfer credit risks to a third party

    Can be used to diversify credit risks

    CDS Spreads and Bond Yields

    Portfolio consisting of a 5-year par yield corporate bond that provides a

    yield of 6% and a long position in a 5-year CDS costing 100 basis points

    per year is (approximately) a long position in a riskless instrument paying

    5% per year

    This shows that CDS spreads should be approximately the same as bond

    yield spreads

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    Valuation

    Suppose that conditional on no earlier default a reference entity has a

    (risk-neutral) probability of default of 2% in each of the next 5 years Assume that the risk-free (LIBOR) rate is 5% per annum with continuous

    compounding

    Assume payments are made annually in arrears, that defaults always

    happen half way through a year, and that the expected recovery rate is

    40%

    Suppose that the breakeven CDS rate is s per dollar of notional principal

    Unconditional Default and Survival Probabilities

    Calculation of PV of Payments (Principal=$1)

    Time (yrs) Survival

    Prob

    Expected

    Paymt

    Discount

    Factor

    PV of Exp

    Pmt

    1 0.9800 0.9800s 0.9512 0.9322s

    2 0.9604 0.9604s 0.9048 0.8690s

    3 0.9412 0.9412s 0.8607 0.8101s

    4 0.9224 0.9224s 0.8187 0.7552s

    5 0.9039 0.9039s 0.7788 0.7040s

    Total 4.0704s

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    Payos from Options: What is the Option Position in Each Case?

    Let K = Strike price, ST = Price of asset at maturity

    Payoff Payoff

    ST STK

    K

    Payoff Payoff

    ST

    ST

    K

    K

    Assets Underlying Exchange-Traded Options

    Stocks

    Foreign Currency

    Stock Indices

    Futures

    Specication of Exchange-Traded Options

    Expiration date

    Strike price

    European or American

    Call or Put (option class)

    Terminology

    Moneyness :

    At-the-money option In-the-money option Out-of-the-money option

    Option class

    Option series

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    Intrinsic value

    Time value

    Dividends & Stock Splits Suppose you own N options with a strike price of K :

    No adjustments are made to the option terms for cash dividends When there is an n-for-m (from m to n) stock split,

    the strike price is reduced to mK=n the number. of options is increased to nN=m

    Stock dividends are handled in a manner similar to stock splits

    Consider a call option to buy 100 shares for $20/share

    How should terms be adjusted:

    for a 2-for-1 stock split? for a 5% stock dividend?

    Market Makers

    Most exchanges use market makers to facilitate options trading A market maker quotes both bid and ask prices when requested

    The market maker does not know whether the individual requesting the

    quotes wants to buy or sell

    Margins

    Margins are required when options are sold

    Warrants

    Warrants are options that are issued (or written) by a corporation or a

    nancial institution

    The number of warrants outstanding is determined by the size of the

    original issue & changes only when they are exercised or when they expire

    Warrants are traded in the same way as stocks

    The issuer settles up with the holder when a warrant is exercised

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    Problem 5 An investor buys for $3 a call with a strike price of $30 and

    sells for $1 call with a strike price of $35. What is the prot from this

    transaction?

    K1

    K2

    Profit

    ST

    payo from a bull spread created using calls

    Stock price Payo from Payo from Total

    range long call option short call option payo

    ST K1 0 0 0K1 < ST < K2 ST K1 0 ST K1ST

    K2

    ST

    K1

    K2

    ST

    K2

    K1

    Bull Spread Using Puts

    Buy a put option with a low price (K1) and sell a put with a high strike

    price (K2)

    Both options have the same expiration date

    K1

    K2

    Profit

    ST

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    Bear Spread Using Puts

    K1

    K2

    Profit

    ST

    Bear Spread Using Calls

    K1

    K2

    Profit

    ST

    Box Spread

    A combination of a bull call spread and a bear put spread

    If all options are European, a box spread is worth the present value of

    the dierence between the strike prices

    If they are American this is not necessarily so

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    Payo from a box spread

    Stock price Payo from Payo from Total

    range bull call spread bear put spread payoST K1 0 K2 K1 K2 K1K1 < ST < K2 ST K1 K2 ST K2 K1ST K2 K2 K1 0 K2 K1

    The value of a box spread is always (K2 K1) erT (if and only if it isan European).

    Buttery Spread

    Involves positions in the same types of options (call or put) with three

    dierent strike prices

    Appropriate strategy for an investor who feels that large stock price

    moves are unlikely

    Buttery Spread Using Calls

    Buy a call with strike price of K1, buy a call with K3, and sell 2 call

    options with K2

    K1 K3

    Profit

    STK2

    Buttery Spread Using Puts

    Buy a put with strike price of K1, buy a put with K3, and sell 2 put

    options with K2

    Calendar Spread

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    The options have the same strike price and dierent expiration date

    Sell a option with short-maturity and buy a option with long-maturity

    Understanding the prot diagram of callendar spread (call option case) If the stock price is very low when the short-maturity option expires

    The short-maturity option is worthless and the value of long-maturityoption is close to zero

    Investor therefore incurs a loss that is close to the cost of settingup the spread initially

    If the stock price; ST, is very high when the short-maturity option expires

    The short-maturity option cost investor ST K, and the long-marurity option is worth a little more than ST K Again, the investor makes a net loss that is close to the cost of

    setting up the spread initially

    If ST is close to K

    the short-maturity option costs the investor either a small amountor nothing at all

    However, the long-maturity option is still quite valuable In this case, a signicant net prot is made

    Prot diagram is drawn on the assumption the long-maturity option is

    sold when the short-maturity option expires

    Calendar Spread Using Calls

    Prot diagrams show the prot when the short-maturity option expires

    on the same day the long-maturity option is sold

    TS

    K

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    Diagonal Spread

    Similar to bull and bear spread except that diagonal spread the expiration

    date of the option is dierent

    Combination

    Taking a position in both calls and puts on the same stock

    A Straddle

    Buying a call and put with the same strike price and expiration date

    If the stock price close to this strike price, the straddle leads to aloss

    Profit

    ST

    K

    Stock price Payo from Payo from Total

    range call put payo

    ST K 0 K ST K STK1 > K ST K 0 ST K

    Strip & Strap

    Strip: buying 1 call and 2 puts with the same strike price and expiration

    date

    Makes more money when the stock price falls signicantly Strap: buying 2 calls and 1 put with the same strike price and expiration

    date

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    The value of the portfolio in 3 months when the stock price becomes $22

    is

    22 0:25 1 = 4:50

    The value of the portfolio in 3 months when the stock price becomes $18

    is

    18 0:25 = 4:50

    The value of the portfolio in 2 months becomes 4.50 whether the stock

    price rises to $22 or falls to $18

    The value of the portfolio today is

    4:5e0:120:25 = 4:3670

    Valuing the Option

    The portfolio that is

    long 0.25 shares

    short 1call option

    is worth 4.367

    The value of the shares is 5:000(= 0:25 20) The value of the option is therefore 0:633(= 5:000 4:367)

    Generalization

    A derivative lasts for time T and is dependent on a stock

    Su

    u

    Sd

    d

    S

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    Consider the portfolio that is long shares and short 1 derivative

    The portfolio is riskless when Su fu = Sd fd or

    =fu fd

    Su Sd

    Value of the portfolio at time T is

    Su fu

    Value of the portfolio today is

    (Su fu)erT

    Another expression for the portfolio value today is S f

    Hence

    f = S (Su fu)erT

    Substituting for we obtain

    f = [pfu + (1 p)fd]erT

    where

    p =erT du

    d

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    Proof.

    f= S (Su fu)erT; = fu fdSu

    Sd

    f= S fu fdSu Sd (Su

    fu fdSu Sd fu)e

    rT

    = (Sfu fd

    Su Sd erT Su fu fd

    Su Sd + fu)erT

    (fu fdu d e

    rT u fu fdu d fu)e

    rT

    = (erT u + (u d)

    u d fu erT u

    u d )erT

    = (erT du

    d

    fu +u erT

    u

    d

    )erT

    = (pfu + (1 p) fd) ert

    (note : 1 erT du d =

    u d erT + du d =

    u erTu d )

    Risk-Neutral Valuation

    f = [pfu + (1 p)fd]erT

    The variables p and (1 p ) can be interpreted as the risk-neutral prob-abilities of up and down movements

    The value of a derivative is its expected payo in a risk-neutral world

    discounted at the risk-free rate

    Irrelevance of Stocks Expected Return

    When we are valuing an option in terms of the underlying stock the

    expected return on the stock is irrelevant

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    Valuing a Call Option

    20

    1.2823

    22

    18

    24.2

    3.2

    19.8

    0.0

    16.2

    0.0

    2.0257

    0.0

    A

    B

    C

    D

    E

    F

    Value at node B

    = e0:120:25(0:6523 3:2 + 0:3477 0) = 2:0257

    Value at node A

    = e0:120:25(0:6523 2:0257 + 0:3477 0) = 1:2823

    A Put Option Example

    K = 52; t = 1yr; r = 5%

    50

    4.1923

    60

    40

    72

    0

    48

    4

    32

    20

    1.4147

    9.4636

    A

    B

    C

    D

    E

    F

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    What Happens When an Option is American

    50

    5.0894

    60

    40

    72

    0

    48

    4

    32

    20

    1.4147

    12.0

    A

    B

    C

    D

    E

    F

    Delta

    Delta () is the ratio of the change in the price of a stock option to the

    change in the price of the underlying stock

    It is the number of units of the stock we should hold for each option

    shortened in order to create riskless hedge

    The value of varies from node to node

    Deta is calculated as:

    =fu fd

    Su SdStock Price = $22Option Price = $1

    Stock Price = $18Option Price = $0

    Stock price = $20Option Price=?

    In the previous example, wec can calculate the value of delta of the call

    as:

    =1

    0

    22 18 = 0:25:This because when the stock price changes from $18 to $22, the option

    price changes from $0 to $1

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    E(ST) = S0erT

    V ar(ST) = S20e

    2T

    e2T 1

    Remark 6 The log normal distribution has the probability density function

    f(x; ; ) =1

    xp

    2e

    (ln(x))2

    22

    for x > 0 where and are the mean and standard deviation of the vari-

    ables natural loga