Risk, Return, and Diversification a Reading Prepared by Pamela Peterson Drake

Total Page:16

File Type:pdf, Size:1020Kb

Risk, Return, and Diversification a Reading Prepared by Pamela Peterson Drake Risk, return, and diversification A reading prepared by Pamela Peterson Drake O U T L I N E 1. Introduction 2. Diversification and risk 3. Modern portfolio theory 4. Asset pricing models 5. Summary 1. Introduction As managers, we rarely consider investing in only one project at one time. Small businesses and large corporations alike can be viewed as a collection of different investments, made at different points in time. We refer to a collection of investments as a portfolio. While we usually think of a portfolio as a collection of securities (stocks and bonds), we can also think of a business in much the same way -- a portfolios of assets such as buildings, inventories, trademarks, patents, et cetera. As managers, we are concerned about the overall risk of the company's portfolio of assets. Suppose you invested in two assets, Thing One and Thing Two, having the following returns over the next year: Asset Return Thing One 20% Thing Two 8% Suppose we invest equal amounts, say $10,000, in each asset for one year. At the end of the year we will have $10,000 (1 + 0.20) = $12,000 from Thing One and $10,000 (1 + 0.08) = $10,800 from Thing Two, or a total value of $22,800 from our original $20,000 investment. The return on our portfolio is therefore: ⎛⎞$22,800-20,000 Return = ⎜⎟= 14% ⎝⎠$20,000 If instead, we invested $5,000 in Thing One and $15,000 in Thing Two, the value of our investment at the end of the year would be: Value of investment =$5,000 (1 + 0.20) + 15,000 (1 + 0.08) = $6,000 + 16,200 = $22,200 and the return on our portfolio would be: ⎛⎞$22,200-20,000 Return = ⎜⎟= 11% ⎝⎠$20,000 which we can also write as: Risk, return, and diversification, a reading prepared by Pamela Peterson Drake 1 ⎡⎤⎛⎞$5,000 ⎡ ⎛⎞$15,000 ⎤ Return = ⎢⎥⎜⎟(0.2) +=⎢ ⎜⎟(0.08) ⎥ 11% ⎣⎦⎝⎠$20,000 ⎣ ⎝⎠$20,000 ⎦ As you can see more immediately by the second calculation, the return on our portfolio is the weighted average of the returns on the assets in the portfolio, where the weights are the proportion invested in each asset. We can generalize the formula for a portfolio return, rp, as the weighted average of the returns of all assets in the portfolio, letting: • i indicate the particular asset in the portfolio, • wi indicate the proportion invested in asset i, • ri indicate the return on asset i, and • S indicate the number of assets in the portfolio The return on the portfolio is: rp = w1r1 + w2r2 + ... + wSrS , which we can write more compactly as: S rwpi= ∑ ri i1= Example: The return on a portfolio Problem Consider a portfolio comprised of three assets, with expected returns and investments of: Asset Expected return Investment A 10% $20,000 B 5% 10,000 C 15% 20,000 What is the expected return on the portfolio? Solution rp = 40% (10%) + 20% (5%) + 40% (15%) rp = 0.04 + 0.01 + 0.06 rp = 0.11 or 11% 2. Diversification and risk "My ventures are not in one bottom trusted Nor to one place; nor is my whole estate Upon the fortune of this present year. Therefore my merchandise makes me not sad" - William Shakespeare, Merchant of Venice. In any portfolio, one investment may do well while another does poorly. The projects' cash flows may be "out of synch" with one another. Let's see how this might happen. Let's look at the idea of "out-of-synchness" in terms of expected returns, since this is what we face when we make financial decisions. Consider Investment One and Investment Two and their probability distributions: Risk, return, and diversification, a reading prepared by Pamela Peterson Drake 2 Scenario Probability of Return on Return on Scenario Investment One Investment Two Boom 30% 20% -10% Normal 50% 0% 0% Recession 20% -20% 45% We see that when Investment One does well, in the boom scenario, Investment Two does poorly. Also, when Investment One does poorly, as in the recession scenario, Investment Two does well. In other words, these investments are out of synch with one another. Now let's look at how their "out-of-synchness" affects the risk of the portfolio of One and Two. If we invest an equal amount in One and Two, the portfolio's return under each scenario is the weighted average of One and Two's returns, where the weights are 50 percent: Scenario Probability Weighted average return Boom 0.30 [0.5 ( 0.20)] + [0.5 (-0.10)] = 0.0500 or 5% Normal 0.50 [0.5 ( 0.00)] + [0.5 ( 0.00)] = 0.0000 or 10% Recession 0.20 [0.5 (-0.20)] + [0.5 ( 0.45)] = 0.1250 or 12.5% The calculation of the expected return and standard deviation for Investment One, Investment Two, and the portfolio consisting of One and Two results in the following the statistics, Return on Return on Return on a Probability of Investment Investment portfolio comprised Scenario scenario One Two of One and Two Boom 30% 20% -10% 5% Normal 50% 0% 0% 0% Recession 20% -20% 45% 12.5% Expected return 2% 6% 4% Standard deviation 14.00% 19.97% 4.77% The expected return on Investment One is 2 percent and the expected return on Investment Two is 6 percent. The return on a portfolio comprised of equal investments of One and Two is expected to be 4 percent. The standard deviation of Investment One 's return is 14 percent and of Investment Two 's return is 19.97 percent, but the portfolio's standard deviation, calculated using the weighted average of the returns on investments One and Two in each scenario, is 4.77 percent. This is less than the standard deviations of each of the individual investments because the returns of the two investments do not move in the same direction at the same time, but rather tend to move in opposite directions. A. The role of covariance and correlation The portfolio comprised of Investments One and Two has less risk than the individual investments because each moves in different directions with respect to the other. A statistical measure of how two variables -- in this case, the returns on two different investments -- move together is the covariance. Covariance is a statistical measure of how one variable changes in relation to changes in another variable. Covariance in this example is calculated in four steps:1 Step 1: For each scenario and investment, subtract the investment's expected value from its possible outcome; 1 You should notice a similarity between the calculation of the covariance and the variance (that you learned in the Measuring Risk reading). In the case of the variance, we took the deviation from the expected value and squared it before weighting it by the probability. In the case of the covariance, we take the deviations for each asset, multiply them, and then weight by the probability. Risk, return, and diversification, a reading prepared by Pamela Peterson Drake 3 Step 2: For each scenario, multiply the deviations for the two investments; Step 3: Weight this product by the scenario's probability; and Step 4: Sum these weighted products to arrive at the covariance. Deviation of Deviation of Investment One's Investment Two's Product return from its return from its of the Weight the product by Scenario Probability expected return expected return deviations the probability Boom 0.30 0.1800 -0.1600 -0.0288 -0.00864 Normal 0.50 -0.0200 -0.0600 0.0012 0.00060 Recession 0.20 -0.2200 0.3900 -0.0858 -0.01716 covariance =-0.02520 As you can see in these calculations, in a boom economic environment, when Investment One is above its expected return (deviation is positive), Investment Two is below its expected return (deviation is negative). In a recession, Investment One's return is below its expected value and Investment Two's return is above its expected value. The tendency is for the returns on these portfolios to co-vary in opposite directions -- producing a negative covariance of -0.0252. We can represent this calculation in a formula, using pi to represent the probability, r to represent the possible return, the ε to represent the expected return: N Covariance p r -E r -E One,Two= ∑ i()( One,i One Two,i Two ) i=1 Let's see the effect of this negative covariance on the risk of the portfolio. The portfolio's variance depends on: 1. the weight of each asset in the portfolio; 2. the standard deviation of each asset in the portfolio; and 3. the covariance of the assets' returns. Let cov1,2 represent the covariance of two assets' returns. We can write the portfolio variance for a two- security portfolio as: 2 2 2 2 Portfolio variance, 2-security portfolio = w1 σ1 + w2 σ2 + 2 w1 w2 cov1,2. The portfolio standard deviation is the square root of the variance, or: Portfolio standard deviation, 2-security portfolio = w12σσ 12 + w 22 22 + 2w 1 w 2 cov 1,2 . More generally, the formula is: NNN 22 Portfolio standard deviation = ∑∑∑wiiσσ + wijijij wσ r i=1 i==≠ 1 j 1 j i Recognizing that the covariance is the product of the correlation and the respective standard deviations, we can also write the formula as: NNN 22 . Portfolio standard deviation = ∑∑∑wiiσ + wij w cov ij i=1 i==≠ 1 j 1 j i We can apply this general formula to our example, with Investment One's characteristics indicated with a 1 and Investment Two's with a 2, Risk, return, and diversification, a reading prepared by Pamela Peterson Drake 4 w1 = 0.50 or 50 percent w2 = 0.50 or 50 percent s1 = 0.1400 or 14.00 percent s2 = 0.1997 or 19.97 percent cov1,2 = -0.0252.
Recommended publications
  • Expected Stock Returns and Volatility Kenneth R
    University of Pennsylvania ScholarlyCommons Finance Papers Wharton Faculty Research 1987 Expected Stock Returns and Volatility Kenneth R. French G. William Schwert Robert F. Stambaugh University of Pennsylvania Follow this and additional works at: http://repository.upenn.edu/fnce_papers Part of the Finance Commons, and the Finance and Financial Management Commons Recommended Citation French, K. R., Schwert, G., & Stambaugh, R. F. (1987). Expected Stock Returns and Volatility. Journal of Financial Economics, 19 (1), 3-29. http://dx.doi.org/10.1016/0304-405X(87)90026-2 At the time of publication, author Robert F. Stambaugh was affiliated with the University of Chicago. Currently, he is a faculty member at the Wharton School at the University of Pennsylvania. This paper is posted at ScholarlyCommons. http://repository.upenn.edu/fnce_papers/363 For more information, please contact [email protected]. Expected Stock Returns and Volatility Abstract This paper examines the relation between stock returns and stock market volatility. We find ve idence that the expected market risk premium (the expected return on a stock portfolio minus the Treasury bill yield) is positively related to the predictable volatility of stock returns. There is also evidence that unexpected stock market returns are negatively related to the unexpected change in the volatility of stock returns. This negative relation provides indirect evidence of a positive relation between expected risk premiums and volatility. Disciplines Finance | Finance and Financial Management Comments At the time of publication, author Robert F. Stambaugh was affiliated with the University of Chicago. Currently, he is a faculty member at the Wharton School at the University of Pennsylvania.
    [Show full text]
  • Estimating Value at Risk
    Estimating Value at Risk Eric Marsden <[email protected]> Do you know how risky your bank is? Learning objectives 1 Understand measures of financial risk, including Value at Risk 2 Understand the impact of correlated risks 3 Know how to use copulas to sample from a multivariate probability distribution, including correlation The information presented here is pedagogical in nature and does not constitute investment advice! Methods used here can also be applied to model natural hazards 2 / 41 Warmup. Before reading this material, we suggest you consult the following associated slides: ▷ Modelling correlations using Python ▷ Statistical modelling with Python Available from risk-engineering.org 3 / 41 Risk in finance There are 1011 stars in the galaxy. That used to be a huge number. But it’s only a hundred billion. It’s less than the national deficit! We used to call them astronomical numbers. ‘‘ Now we should call them economical numbers. — Richard Feynman 4 / 41 Terminology in finance Names of some instruments used in finance: ▷ A bond issued by a company or a government is just a loan • bond buyer lends money to bond issuer • issuer will return money plus some interest when the bond matures ▷ A stock gives you (a small fraction of) ownership in a “listed company” • a stock has a price, and can be bought and sold on the stock market ▷ A future is a promise to do a transaction at a later date • refers to some “underlying” product which will be bought or sold at a later time • example: farmer can sell her crop before harvest,
    [Show full text]
  • A Securitization-Based Model of Shadow Banking with Surplus Extraction and Credit Risk Transfer
    A Securitization-based Model of Shadow Banking with Surplus Extraction and Credit Risk Transfer Patrizio Morganti∗ August, 2017 Abstract The paper provides a theoretical model that supports the search for yield motive of shadow banking and the traditional risk transfer view of securitization, which is consistent with the factual background that had characterized the U.S. financial system before the recent crisis. The shadow banking system is indeed an important provider of high-yield asset-backed securi- ties via the underlying securitized credit intermediation process. Investors' sentiment on future macroeconomic conditions affects the reservation prices related to the demand for securitized assets: high-willing payer (\optimistic") investors are attracted to these investment opportu- nities and offer to intermediaries a rent extraction incentive. When the outside wealth is high enough that securitization occurs, asset-backed securities are used by intermediaries to extract the highest feasible surplus from optimistic investors and to offload credit risk. Shadow banking is pro-cyclical and securitization allows risks to be spread among market participants coherently with their risk attitude. Keywords: securitization, shadow banking, credit risk transfer, surplus extraction JEL classification: E44, G21, G23 1 Introduction During the last four decades we witnessed to fundamental changes in financial techniques and financial regulation that have gradually transformed the \originate-to-hold" banking model into a \originate-to-distribute" model based on a securitized credit intermediation process relying upon i) securitization techniques, ii) securities financing transactions, and iii) mutual funds industry.1 ∗Tuscia University in Viterbo, Department of Economics and Engineering. E-mail: [email protected]. I am most grateful to Giuseppe Garofalo for his continuous guidance and support.
    [Show full text]
  • The Cross-Section of Volatility and Expected Returns
    THE JOURNAL OF FINANCE • VOL. LXI, NO. 1 • FEBRUARY 2006 The Cross-Section of Volatility and Expected Returns ANDREW ANG, ROBERT J. HODRICK, YUHANG XING, and XIAOYAN ZHANG∗ ABSTRACT We examine the pricing of aggregate volatility risk in the cross-section of stock returns. Consistent with theory, we find that stocks with high sensitivities to innovations in aggregate volatility have low average returns. Stocks with high idiosyncratic volatility relative to the Fama and French (1993, Journal of Financial Economics 25, 2349) model have abysmally low average returns. This phenomenon cannot be explained by exposure to aggregate volatility risk. Size, book-to-market, momentum, and liquidity effects cannot account for either the low average returns earned by stocks with high exposure to systematic volatility risk or for the low average returns of stocks with high idiosyncratic volatility. IT IS WELL KNOWN THAT THE VOLATILITY OF STOCK RETURNS varies over time. While con- siderable research has examined the time-series relation between the volatility of the market and the expected return on the market (see, among others, Camp- bell and Hentschel (1992) and Glosten, Jagannathan, and Runkle (1993)), the question of how aggregate volatility affects the cross-section of expected stock returns has received less attention. Time-varying market volatility induces changes in the investment opportunity set by changing the expectation of fu- ture market returns, or by changing the risk-return trade-off. If the volatility of the market return is a systematic risk factor, the arbitrage pricing theory or a factor model predicts that aggregate volatility should also be priced in the cross-section of stocks.
    [Show full text]
  • CHAPTER 7 Smart Excel Appendix Appendix Contents
    CHAPTER 7 Smart Excel Appendix Appendix Contents Excel prerequisites Relative, absolute, and mixed cell references, covered in Chapter 4 Learn to solve for Expected stock returns using the historical approach Expected stock returns using the probabilistic approach Expected stock returns using the CAPM approach Expected portfolio return and risk measures Use the Smart Excel spreadsheets and animated tutorials at the Smart Finance section of http://www.cengage.co.uk/megginson. EXCEL PREREQUISITES There are no new Excel features used in this appendix, but there is extensive use of absolute and mixed cell references. This material is reviewed and extended on the Excel Prereqs tab of the Chapter 7 file located at the Smart Finance Web site. EXPECTED RETURN Problem: You are considering investing in four companies and want to determine the expected return on each investment, if held on its own, over the next year. You are interested in comparing the expected return using three approaches: historical, probabilistic, and CAPM. You also want to find the return on a portfolio invested equally in each of the four investments. Last, you want to assess the risk of the potential investments. Information on the investments and current market conditions is provided here and below. You have return information for the 1964–2003 period. The current Treasury bill rate is 2.2%, and the average Treasury bill return over the period 1964–2003 was 4.1%. The expected return on a market portfolio is 11%. You want to consider returns under three possible economic scenarios over the next year: weak economy, average economy, strong economy.
    [Show full text]
  • Speculation and Risk in Foreign Exchange Markets
    Chapter 7 Speculation and Risk in the Foreign Exchange Market © 2018 Cambridge University Press 7-1 7.1 Speculating in the Foreign Exchange Market • Uncovered foreign money market investments • Kevin Anthony, a portfolio manager, is considering several ways to invest $10M for 1 year • The data are as follows: • USD interest rate: 8.0% p.a.; GBP interest rate: 12.0% p.a.; Spot: $1.60/£ • Remember that if Kevin invests in the USD-denominated asset at 8%, after 1 year he will have × 1.08 = $10. • What if Kevin invests his $10M in the pound money market, but decides not to hedge the foreign$10 exchange risk?8 © 2018 Cambridge University Press 7-2 7.1 Speculating in the Foreign Exchange Market • As before, we can calculate his dollar return in three steps: • Convert dollars into pounds in the spot market • The $10M will buy /($1.60/£) = £6. at the current spot exchange rate • This is Kevin’s pound principal. $10 25 • Calculate pound-denominated interest plus principal • Kevin can invest his pound principal at 12% yielding a return in 1 year of £6. × 1.12 = £7 • Sell the pound principal plus interest at the spot exchange rate in 1 year 25 • 1 = × ( + 1, $/£) ( + 1) = ( + 1) × ( / ) – (1 + 0.08) • £7 £7 $10 © 2018 Cambridge University Press 7-3 Return and Excess Return in Foreign Market • We can use the previous calculation to deduce a formula for calculating the return in the foreign market, 1 rt( +=1) ×+( 1it( ,£)) × St( + 1) St( ) • The return on the British investment is uncertain because of exchange rate uncertainty.
    [Show full text]
  • Economic Aspects of Securitization of Risk
    ECONOMIC ASPECTS OF SECURITIZATION OF RISK BY SAMUEL H. COX, JOSEPH R. FAIRCHILD AND HAL W. PEDERSEN ABSTRACT This paper explains securitization of insurance risk by describing its essential components and its economic rationale. We use examples and describe recent securitization transactions. We explore the key ideas without abstract mathematics. Insurance-based securitizations improve opportunities for all investors. Relative to traditional reinsurance, securitizations provide larger amounts of coverage and more innovative contract terms. KEYWORDS Securitization, catastrophe risk bonds, reinsurance, retention, incomplete markets. 1. INTRODUCTION This paper explains securitization of risk with an emphasis on risks that are usually considered insurable risks. We discuss the economic rationale for securitization of assets and liabilities and we provide examples of each type of securitization. We also provide economic axguments for continued future insurance-risk securitization activity. An appendix indicates some of the issues involved in pricing insurance risk securitizations. We do not develop specific pricing results. Pricing techniques are complicated by the fact that, in general, insurance-risk based securities do not have unique prices based on axbitrage-free pricing considerations alone. The technical reason for this is that the most interesting insurance risk securitizations reside in incomplete markets. A market is said to be complete if every pattern of cash flows can be replicated by some portfolio of securities that are traded in the market. The payoffs from insurance-based securities, whose cash flows may depend on Please address all correspondence to Hal Pedersen. ASTIN BULLETIN. Vol. 30. No L 2000, pp 157-193 158 SAMUEL H. COX, JOSEPH R. FAIRCHILD AND HAL W.
    [Show full text]
  • Incentives and Tranche Retention in Securitisation: a Screening Model
    Incentives and Tranche Retention in Securitisation: A Screening Model Ingo Fender (Bank for International Settlements) and Janet Mitchell (National Bank of Belgium and CEPR)y First draft: November, 2008z This draft: May, 2009 Abstract This paper examines the power of di¤erent contractual mechanisms to in‡uence an originator’schoice of costly e¤ort to screen borrowers when the originator plans to securitise its loans. The analysis focuses on three potential mechanisms: the originator holds a “vertical slice”, or share of the portfolio; the originator holds the equity tranche of a structured …nance transaction; the originator holds the mezzanine tranche, rather than the equity tranche. These mechanisms will result in di¤ering levels of screening, and the di¤erences arise from varying sensitivities to a systematic risk factor. Equity tranche retention is not always the most e¤ective mechanism. The equity tranche can be dominated by either a vertical slice or a mezzanine tranche if the probability of a downturn is likely and if the equity tranche is likely to be depleted in a downturn. In addition, a vertical slice is unlikely to dominate both the equity tranche and the mezzanine tranche, unless the vertical slice is very "thick". Monetary and Economic Department, Bank for International Settlements, Central- bahnplatz 2, 4002 Basel, Switzerland, tel: +41 61 280 8415, email: [email protected] yFinancial Stability Department, National Bank of Belgium, Boulevard de Berlaimont 14, B-1000 Brussels, Belgium, tel: +32 2 221 3459, email: [email protected] zThe views expressed in this paper remain those of the authors and do not necessarily re‡ect those of the BIS or the NBB.
    [Show full text]
  • The Ellevest Difference: the Fine Print on Expected Returns 2
    THE ELLEVEST DIFFERENCE: THE FINE PRINT ON EXPECTED RETURNS 2 We received a tremendous amount of feedback from women after we introduced Ellevest. Some of our mathematically inclined users put themselves through the paces of trying to calculate what we’re projecting for portfolio returns based upon our forecasts. Some have then asked why our numbers might appear lower than they may have expected. After all, investment professionals are forecasting global equities to return 4.5–7.1% in the long term,1 and our forecasts appear to project returns closer to 3–5% over a long horizon. So that begs the question: How are Ellevest’s forecasts different? Why are Ellevest’s forecasts different from those of other digital advisors, or from what investment professionals are predicting in the press? It’s not because we are pessimists, or claim to know where markets are headed. And it’s ​certainly​ not because we think our recommended portfolios will underperform other low-cost portfolios with similar asset allocations. Yes, our forecasts are different. That’s because, unlike other digital advisors who show forecasts,​ we account for realities such as taxes and fund fees, and build layers of conservatism into the projections we provide to you. Specifically, our forecasts: ● Show a higher likelihood of achievement.​ We shoot to get you to your goals in 70% of markets, while other digital advisors who show forecasts shoot for 50% ● Account for the sequence and magnitude of investment returns,​ known as compounding (averages published in the press aren’t usually compounded) ● Include more poor market scenarios​, which is more consistent with what has been seen historically 1 From 2019 global economic and investment outlook publications from The Vanguard Group and BlackRock Investment Institute.
    [Show full text]
  • The Moral Hazard Theory of Corporate Financial Structure: Empirical Tests
    ,.A '^ WORKING PAPER ALFRED P. SLOAN SCHOOL OF MANAGEMENT THE MORAL HAZARD THEORY OF CORPORATE FINANCIAL STRUCTURE: EMPIRICAL TESTS Scott Williamson Wr 1083-79 September 1979 MASSACHUSETTS INSTITUTE OF TECHNOLOGY 50 MEMORIAL DRIVE CAMBRIDGE, MASSACHUSETTS 02139 THE MORAL HAZARD THEORY OF COHPORATE financial STRUCTURE: EMPIRICAL TESTS Scott Williamson WI' 1083-79 September 1979 The Moral Hazard Theory of Corporate Financial Structure: .Empirical Tests The development of the theory of optimal corporate financial structure has been based on the critical assumption that the value of the equity is maximized at the level of debt which maximizes the market value of the firm. Recently, however, Myers (1977) illustrated the breakdov/n of that assumption under very plausible conditions. Those conditions produce a conflict between bondholders and stockholders, leading to the application of the term moral hazard. This paper is an attempt to use a large sample of finns to test the inoral hazard theory against others found in the literature. Although the tests can- not conclusively prove one theory correct and the others incorrect, they will add information which mey be of value in further theoretical development. Section I reviews the theory of optimal capital structure. Section II describes the moral hazard theory. Sections III and IV describe the tests and the results. 1 h^'\i>^ J. The Theory of Optimal Capital Structure With the publication of their now famous paper (1953) Modigliani and Miller (MM) laid the traditional theory of optimal corporate capital structure open to inspection and criticism. Until that time, most discussion focused not on the value of the firm's securities at different levels of debt financing, but on v/hich accounting items were capitalized to give that value.
    [Show full text]
  • The Time-Series Relations Among Expected Return, Risk, and Book-To-Marketଝ
    Journal of Financial Economics 54 (1999) 5}43 The time-series relations among expected return, risk, and book-to-marketଝ Jonathan Lewellen* William E. Simon Graduate School of Business Administration, University of Rochester, Rochester, NY 14627, USA Received 8 August 1997; received in revised form 20 October 1998 Abstract This paper examines the time-series relations among expected return, risk, and book- to-market (B/M) at the portfolio level. I "nd that B/M predicts economically and statistically signi"cant time-variation in expected stock returns. Further, B/M is strongly associated with changes in risk, as measured by the Fama and French (1993) (Journal of Financial Economics, 33, 3}56) three-factor model. After controlling for risk, B/M provides no incremental information about expected returns. The evidence suggests that the three-factor model explains time-varying expected returns better than a character- istics-based model. ( 1999 Elsevier Science S.A. All rights reserved. JEL classixcation: G12; G14 Keywords: Asset pricing; Book-to-market; Time-varying risk; Mispricing * Fax: #1-617-258-8408. E-mail address: [email protected] (J. Lewellen) ଝI am grateful to G. William Schwert, Jerold Warner, and especially Jay Shanken for guidance and encouragement. This paper has also bene"ted from the comments of Greg Bauer, Ken French (the referee), Christoph Hinkelmann, S.P. Kothari, John Long, Susan Shu, Peter Wysocki, and seminar participants at the London Business School, MIT, UCLA, UC-Berkeley, University of Illinois, University of Rochester, Yale School of Management, and the 1997 Southern Finance Association meetings. 0304-405X/99/$ - see front matter ( 1999 Elsevier Science S.A.
    [Show full text]
  • Xinfu Chen Mathematical Finance II
    Xinfu Chen Mathematical Finance II Department of mathematics, University of Pittsburgh Pittsburgh, PA 15260, USA ii MATHEMATICAL FINANCE II Course Outline This course is an introduction to modern mathematical ¯nance. Topics include 1. single period portfolio optimization based on the mean-variance analysis, capital asset pricing model, factor models and arbitrage pricing theory. 2. pricing and hedging derivative securities based on a fundamental state model, the well-received Cox-Ross-Rubinstein's binary lattice model, and the celebrated Black-Scholes continuum model; 3. discrete-time and continuous-time optimal portfolio growth theory, in particular the universal log- optimal pricing formula; 4. necessary mathematical tools for ¯nance, such as theories of measure, probability, statistics, and stochastic process. Prerequisites Calculus, Knowledge on Excel Spreadsheet, or Matlab, or Mathematica, or Maple. Textbooks David G. Luenberger, Investment Science, Oxford University Press, 1998. Xinfu Chen, Lecture Notes, available online www.math.pitt.edu/~xfc. Recommended References Steven Roman, Introduction to the Mathematics of Finance, Springer, 2004. John C. Hull, Options, Futures and Other Derivatives, Fourth Edition, Prentice-Hall, 2000. Martin Baxter and Andrew Rennie, Financial Calculus, Cambridge University Press, 1996. P. Wilmott, S. Howison & J. Dewynne, The Mathematics of Financial Derviatives, CUP, 1999. Stanley R. Pliska, Inroduction to Mathematical Finance, Blackwell, 1999. Grading Scheme Homework 40 % Take Home Midterms 40% Final 40% iii iv MATHEMATICAL FINANCE II Contents MATHEMATICAL FINANCE II iii 1 Mean-Variance Portfolio Theory 1 1.1 Assets and Portfolios . 1 1.2 The Markowitz Portfolio Theory . 9 1.3 Capital Asset Pricing Model . 14 1.3.1 Derivation of the Market Portfolio .
    [Show full text]