Makowitz

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    BornAugust 24, 1927 (age 85)

    Chicago, Illinois, USA

    Nationality United States

    Institution

    Harry Markowitz Company

    Rady School of Management at the

    University of California at San Diego

    Baruch College of the City University

    of New York

    RAND Corporation

    Cowles Commission

    Field Financial economics

    Alma mater University of Chicago, (PhD)

    Opposed John Burr Williams

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    Influences

    Milton Friedman

    Tjalling Koopmans

    Jacob Marschak

    Leonard Savage

    Contributions

    Modern Portfolio Theory

    Efficient/ Markowitz Frontier

    Sparse Matrix Methods

    SIMSCRIPT

    Awards

    John von Neumann Theory Prize

    (1989)

    The Sveriges Riksbank Prize in

    Economic Sciences in Memory of

    Alfred Nobel (1990)

    Information at IDEAS/RePEc

    Introduction

    Harry Markowitz was born on August 24, 1927 in Chicago, to his Jewish parents Morris andMildred Markowitz.[1]During high school, Markowitz developed an interest in physics and

    philosophy, in particular the ideas ofDavid Hume, an interest he continued to follow during his

    undergraduate years at the University of Chicago. After receiving his B.A., Markowitz decided

    to continue his studies at the University of Chicago, choosing to specialize in economics. Therehe had the opportunity to study under important economists, including Milton Friedman, Tjalling

    Koopmans, Jacob Marschakand Leonard Savage. While still a student, he was invited to become

    a member of the Cowles Commission for Research in Economics, which was in Chicago at thetime.

    Markowitz chose to apply mathematics to the analysis of the stock market as the topic for his

    dissertation. Jacob Marschak, who was the thesis advisor, encouraged him to pursue the topic,noting that it had also been a favorite interest ofAlfred Cowles, the founder of the Cowles

    Commission. While researching the then current understanding of stock prices, which at the time

    consisted in the present value model ofJohn Burr Williams, Markowitz realized that the theorylacks an analysis of the impact of risk. This insight led to the development of his seminal theory

    ofportfolio allocation under uncertainty, published in 1952 by the Journal of Finance.

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    In 1952, Harry Markowitz went to work for the RAND Corporation, where he met George

    Dantzig. With Dantzig's help, Markowitz continued to research optimization techniques, furtherdeveloping the critical line algorithm for the identification of the optimal mean-variance

    portfolios, relying on what was later named the Markowitz frontier. In 1955, he received a PhD

    from the University of Chicago with a thesis on the portfolio theory. The topic was so novel that,

    while Markowitz was defending his dissertation, Milton Friedman argued his contribution wasnot economics.[3]During 19551956 Markowitz spent a year at the Cowles Foundation, which

    had moved to Yale University, at the invitation ofJames Tobin. He published the critical line

    algorithm in a 1956 paper and used this time at the foundation to write a book on portfolioallocation which was published in 1959.

    Markowitz won the Nobel Memorial Prize in Economic Sciences in 1990 while a professor of

    finance at Baruch College of the City University of New York. In the preceding year, he received

    the John von Neumann Theory Prize from the Operations Research Society of America (now

    Institute for Operations Research and the Management Sciences, INFORMS) for hiscontributions in the theory of three fields: portfolio theory; sparse matrix methods; and

    simulation language programming (SIMSCRIPT). Sparse matrix methods are now widely usedto solve very large systems of simultaneous equations whose coefficients are mostly zero.

    SIMSCRIPT has been widely used to program computer simulations of manufacturing,transportation, and computer systems as well as war games. SIMSCRIPT (I) included the Buddy

    memory allocation method, which was also developed by Markowitz.

    The company that would become CACI International was founded by Herb Karr and Harry

    Markowitz on July 17, 1962 as California Analysis Center, Inc. They helped develop

    SIMSCRIPT, the first simulation programming language, at RAND and after it was released tothe public domain, CACI was founded to provide support and training for SIMSCRIPT.

    In 1968, Markowitz joined Arbitrage Management company founded by Michael Goodkin.Working with Paul Samuelson and Robert Merton he created a hedge fund that represents the

    first known attempt at computerized arbitrage trading. He took over as chief executive in 1970.

    After a successful run as a private hedge fund, AMC was sold to Stuart & Co. in 1971. A yearlater, Markowitz left the company.

    Markowitz now divides his time between teaching (he is an adjunct professor at the Rady Schoolof Management at the University of California at San Diego, UCSD); video casting lectures; and

    consulting (out of his Harry Markowitz Company offices). He currently serves on the Advisory

    Board ofSkyView Investment Advisors, an alternative investment advisory firm and fund of

    hedge funds. Markowitz also serves on the Investment Committee of LWI Financial Inc.("Loring Ward"), a San Jose, California-based investment advisor; on the advisory panel of

    Robert D. Arnott's Newport Beach, California based investment management firm, Research

    Affiliates; on the Advisory Board of Mark Hebner's Irvine, California and internet basedinvestment advisory firm, Index Funds Advisors; and as an advisor to the Investment Committee

    of1st Global, a Dallas, Texas-based wealth management and investment advisory firm.

    Markowitz is co-founder and Chief Architect ofGuidedChoice, a 401(k) managed accounts

    provider and investment advisor. Markowitzs more recent work has included designing the

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    backbone software analytics for the GuidedChoice investment solution and heading the

    GuidedChoice Investment Committee. He is actively involved in designing the next step in theretirement process: assisting retirees with wealth distribution through GuidedSpending.

    Research

    AMarkowitz Efficient Portfolio is one where no added diversification can lower the portfolio's

    riskfor a given return expectation (alternately, no additional expected return can be gainedwithout increasing the risk of the portfolio). The Markowitz Efficient Frontier is the set of all

    portfolios that will give the highest expected return for each given level of risk. These concepts

    of efficiency were essential to the development of the Capital Asset Pricing Model.

    Markowitz also co-edited the textbookThe Theory and Practice of Investment Managementwith

    Frank J. Fabozzi ofYale School of Management.

    Harry Markowitz Model

    Introduction

    Harry Markowitz put forward this model in 1952. It assists in the selection of the most efficient

    by analyzing various possible portfolios of the given securities. By choosing securities that do

    not 'move' exactly together, the HM model shows investors how to reduce their risk. The HM

    model is also called Mean-Variance Model due to the fact that it is based on expected returns(mean) and the standard deviation (variance) of the various portfolios. Harry Markowitz made

    the following assumption while developing the HM model, which were :

    1. Risk of a portfolio is based on the variability of returns from the said portfolio.

    2. An investor is risk averse.

    3. An investor prefers to increase consumption.

    4. The investor's utility function is concave and increasing, due to his risk aversion and

    consumption preference.

    5. Analysis is based on single period model ofinvestment.

    6. An investor either maximizes his portfolio return for a given level of risk or maximum return

    for minimum risk.

    7. An investor is rational in nature.

    To choose the best portfolio from a number of possible portfolios, each with different return and

    risk, two separate decisions are to be made :

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    1. Determination a set of efficient portfolios.

    2. Selection of best portfolio out of the efficient set.

    Determining the Efficient Set

    A portfolio that gives maximum return for a given risk, or minimum risk for given return is an

    efficient portfolio. Thus, portfolios are selected as follows:

    (a) From the portfolios that have the same return, the investor will prefer the portfolio with lower

    risk, and

    (b) From the portfolios that have the same risk level, an investor will prefer the portfolio with

    higher rate of return.

    Figure 1: Risk-Return of Possible Portfolios

    As the investor is rational, they would like to have higher return. And as he is risk averse, he

    wants to have lower risk. In Figure 1, the shaded area PVWP includes all the possible securities

    an investor can invest in. The efficient portfolios are the ones that lie on the boundary of PQVW.For example, at risk level x2, there are three portfolios S, T, U. But portfolio S is called the

    efficient portfolio as it has the highest return, y2, compared to T and U. All the portfolios that lie

    on the boundary of PQVW are efficient portfolios for a given risk level.

    The boundary PQVW is called the Efficient Frontier. All portfolios that lie below the Efficient

    Frontier are not good enough because the return would be lower for the given risk. Portfolios thatlie to the right of the Efficient Frontier would not be good enough, as there is higher risk for a

    given rate of return. All portfolios lying on the boundary of PQVW are called Efficient

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    Portfolios. The Efficient Frontier is the same for all investors, as all investors want maximum

    return with the lowest possible risk and they are risk averse.

    Choosing the best Portfolio

    For selection of the optimal portfolio or the best portfolio, the risk-return preferences areanalyzed. An investor who is highly risk averse will hold a portfolio on the lower left hand of the

    frontier, and an investor who isnt too risk averse will choose a portfolio on the upper portion ofthe frontier.

    Figure 2: Risk-Return Indifference Curves

    Figure 2 shows the risk-return indifference curve for the investors. Indifference curves C1, C2

    and C3 are shown. Each of the different points on a particular indifference curve shows adifferent combination of risk and return, which provide the same satisfaction to the investors.

    Each curve to the left represents higher utility or satisfaction. The goal of the investor would be

    to maximize his satisfaction by moving to a curve that is higher. An investor might have

    satisfaction represented by C2, but if his satisfaction/utility increases, he/she then moves to curveC3 Thus, at any point of time, an investor will be indifferent between combinations S 1 and S2, or

    S5 and S6.

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    Figure 3: The Efficient Portfolio

    The investor's optimal portfolio is found at the point of tangency of the efficient frontier with the

    indifference curve. This point marks the highest level of satisfaction the investor can obtain. This

    is shown in Figure 3. R is the point where the efficient frontier is tangent to indifference curveC3, and is also an efficient portfolio. With this portfolio, the investor will get highest satisfaction

    as well as best risk-return combination. Any other portfolio, say X, isn't the optimal portfolio

    even though it lies on the same indifference curve as it is outside the efficient frontier. PortfolioY is also not optimal as it does not lie on the indifference curve, even though it lies in the

    portfolio region. Another investor having other sets of indifference curves might have some

    different portfolio as his best/optimal portfolio.

    All portfolios so far have been evaluated in terms of risky securities only, and it is possible to

    include risk-free securities in a portfolio as well. A portfolio with risk-free securities will enable

    an investor to achieve a higher level of satisfaction. This has been explained in Figure 4.

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    Figure 4: The Combination of Risk-Free Securities with the Efficient Frontier and CML

    R1 is the risk-free return, or the return from government securities, as government securities have

    no risk. R1PX is drawn so that it is tangent to the efficient frontier. Any point on the line R1PX

    shows a combination of different proportions of risk-free securities and efficient portfolios. Thesatisfaction an investor obtains from portfolios on the line R1PX is more than the satisfaction

    obtained from the portfolio P. All portfolio combinations to the left of P show combinations of

    risky and risk-free assets, and all those to the right of P represent purchases of risky assets madewith funds borrowed at the risk-free rate.

    In the case that an investor has invested all his funds, additional funds can be borrowed at risk-free rate and a portfolio combination that lies on R1PX can be obtained. R1PX is known as the

    Capital Market Line (CML). this line represents the risk-return trade off in the capital market.

    The CML is an upward sloping curve, which means that the investor will take higher risk if the

    return of the portfolio is also higher. The portfolio P is the most efficient portfolio, as it lies onboth the CML and Efficient Frontier, and every investor would prefer to attain this portfolio, P.

    The P portfolio is known as the Market Portfolio and is also the most diversified portfolio. It

    consists of all shares and other securities in the capital market.

    In the market for portfolios that consists of risky and risk-free securities, the CML represents the

    equilibrium condition. The Capital Market Line says that the return from a portfolio is the risk-

    free rateplus risk premium. Risk premium is the product of the market price of risk and thequantity of risk, and the risk is the standard deviation of the portfolio.

    The CML equation is :

    RP = IRF + (RM - IRF)P/M

    Where,

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    RP = Expected Return of Portfolio

    RM = Return on the Market Portfolio

    IRF = Risk-Free rate ofinterest

    M = Standard Deviation of the market portfolio

    P = Standard Deviation of portfolio

    (RM - IRF)/M is the slope of CML. (RM - IRF) is a measure of the risk premium, or the reward for

    holding risky portfolio instead of risk-free portfolio. M is the risk of the market portfolio.Therefore, the slope measures the reward per unit of market risk.

    The characteristic features of CML are:

    1. At the tangent point, i.e. Portfolio P, is the optimum combination of risky investments and themarket portfolio.

    2. Only efficient portfolios that consist of risk free investments and the market portfolio P lie on

    the CML.

    3. CML is always upward sloping as the price of risk has to be positive. A rational investor willnot invest unless he knows he will be compensated for that risk.

    Figure 5: CML and Risk-Free Lending and Borrowing

    Figure 5 shows that an investor will choose a portfolio on the efficient frontier, in the absence ofrisk-free investments. But when risk-free investments are introduced, the investor can choose the

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    portfolio on the CML (which represents the combination of risky and risk-free investments). This

    can be done with borrowing or lending at the risk-free rate of interest (IRF) and the purchase ofefficient portfolio P. The portfolio an investor will choose depends on his preference of risk. The

    portion from IRF to P, is investment in risk-free assets and is called Lending Portfolio. In this

    portion, the investor will lend a portion at risk-free rate. The portion beyond P is called

    Borrowing Portfolio, where the investor borrows some funds at risk-free rate to buy more ofportfolio P.

    Demerits of the HM Model

    1. It requires lots of data to be included. An investor must obtain variances of return, covarianceof returns and estimates of return for all the securities in a portfolio.

    2. There are numerous calculations involved that are complicated because from a given set ofsecurities, a very large number of portfolio combinations can be made.

    3. The expected return and variance will also have to computed for each securities

    The contribution for which Harry Markowitz now receives his award was first published

    in an essay entitled "Portfolio Selection" (1952), and later, more extensively, in his book,

    Portfolio Selection: Efficient Diversification(1959). The so-called theory of portfolio

    selection that was developed in this early work was originally a normative theory for

    investment managers, i.e., a theory for optimal investment of wealth in assets which

    differ in regard to their expected return and risk. On a general level, of course,

    investment managers and academic economists have long been aware of the necessityof taking returns as well as risk into account: "all the eggs should not be placed in the

    same basket". Markowitz's primary contribution consisted of developing a rigorously

    formulated, operational theory for portfolio selection under uncertainty - a theory which

    evolved into a foundation for further research in financial economics.

    Markowitz showed that under certain given conditions, an investor's portfolio choice can

    be reduced to balancing two dimensions, i.e., the expected return on the portfolio and

    its variance. Due to the possibility of reducing risk through diversification, the risk of the

    portfolio, measured as its variance, will depend not only on the individual variances of

    the return on different assets, but also on the pairwise covariances of all assets.

    Hence, the essential aspect pertaining to the risk of an asset is not the risk of each

    asset in isolation, but the contribution of each asset to the risk of the aggregate portfolio.

    However, the "law of large numbers" is not wholly applicable to the diversification of

    risks in portfolio choice because the returns on different assets are correlated in

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    practice. Thus, in general, risk cannot be totally eliminated, regardless of how many

    types of securities are represented in a portfolio.

    In this way, the complicated and multidimensional problem of portfolio choice with

    respect to a large number of different assets, each with varying properties, is reduced to

    a conceptually simple two-dimensional problem - known as mean-variance analysis. In

    an essay in 1956, Markowitz also showed how the problem of actually calculating the

    optimal portfolio could be solved. (In technical terms, this means that the analysis is

    formulated as a quadratic programming problem; the building blocks are a quadratic

    utility function, expected returns on the different assets, the variance and covariance of

    the assets and the investor's budget restrictions.) The model has won wide acclaim due

    to its algebraic simplicity and suitability for empirical applications.

    Generally speaking, Markowitz's work on portfolio theory may be regarded as having

    established financial micro analysis as a respectable research area in economicanalysis.