Ebook Copeland''s financial theory and corporate policy: Part 1

Ebook Copeland''s financial theory and corporate policy: Part 1 presents the following content: Introduction: capital markets, consumption, and investment; investment decisions: the certainty case; more advanced capital budgeting topics; the theory of choice: utility theory given uncertainty; state-preference theory; objects of choice: mean-variance uncertainty; market equilibrium: CAPM and APT; pricing contingent claims: option pricing theory and evidence; futures contracts and markets; efficient capital markets: theory. Please refer to the documentation for more details.

Financial Theory and Corporate Policy/ THOMAS E COPELAND Professor of Finance University of California at Los Angeles Firm Consultant, Finance McKinsey & Company, Inc J FRED WESTON Cordner Professor of Managerial Economics and Finance University of California at Los Angeles • •• ADDISON-WESLEY PUBLISHING COMPANY Reading, Massachusetts • Menlo Park, California • New York Don Mills, Ontario • Wokingham, England • Amsterdam Bonn • Sydney • Singapore • Tokyo • Madrid • San Juan This book is dedicated to our wives, Casey and June, who have provided their loving support; and to the pioneers in the development of the modern theory of finance: Hirshleifer, Arrow, Debreu, Miller, Modigliani, Markowitz, Sharpe, Lintner, Jensen, Fama, Roll, Black, Scholes, Merton, Ross, and others cited in the pages that follow Without their intellectual leadership this text could not exist Library of Congress Cataloging-in-Publication Data Copeland, Thomas E., 1946– Financial theory and corporate policy Includes bibliographies and index Corporations—Finance I Weston, J Fred (John Fred), 1916– II Title HG4011.C833 1988 658.1'5 87-12595 ISBN 0-201-10648-5 Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks Where those designations appear in this book, and Addison-Wesley was aware of a trademark claim, the designations have been printed in initial caps or all caps Copyright © 1988 by Addison-Wesley Publishing Company, Inc All rights reserved No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher Printed in the United States of America Published simultaneously in Canada ABCDEFGHIJ–DO-898 Preface In this third edition we seek to build on our experiences and the suggestions of users of the two previous editions The feedback that we have received from all sources confirms our original judgment that there is a need for a book like Financial Theory and Corporate Policy Therefore, we will continue to emphasize our original objectives for the book Primarily, our aim is to provide a bridge to the more theoretical articles and treatises on finance theory For doctoral students the book provides a framework of conceptual knowledge, enabling the students to understand what the literature on financial theory is trying to and how it all fits together For MBAs it provides an in-depth experience with the subject of finance Our aim here is to equip the MBA for his or her future development as a practicing executive We seek to prepare the MBA for reading the significant literature of the past, present, and future This will help the practicing financial executive keep up to date with developments in finance theory, particularly as they affect the financial executive's own thinking processes in making financial decisions As before, our emphasis is on setting forth clearly and succinctly the most important concepts in finance theory We have given particular attention to testable propositions and to the literature that has developed empirical tests of important elements of finance theory In addition, we have emphasized applications so that the nature and uses of finance theory can be better understood A PURPOSE AND ORGANIZATION Over the past 30 years a branch of applied microeconomics has been developed and specialized into what is known as modern finance theory The historical demarcation point was roughly 1958, when Markowitz and Tobin were working on the theory of portfolio selection and Modigliani and Miller were working on capital structure and valuation Prior to 1958, finance was largely a descriptive field of endeavor Since then major theoretical thrusts have transformed the field into a positive science As evidence of the changes that have taken place we need only look at the types of people who teach in the schools of business Fifty years ago the faculty were drawn from the ranks of business and government They were respected and experienced statesmen within their fields Today, finance faculty are predominantly academicians in the traditional sense of the word The majority of them have no business experience except for consulting Their interest iii iV PREFACE and training is in developing theories to explain economic behavior, then testing them with the tools provided by statistics and econometrics Anecdotal evidence and individual business experience have been superseded by the analytic approach of modern finance theory The rapid changes in the field of finance have profound implications for management education As usual, the best students (and the best managers) possess rare intuition, initiative, common sense, strong reading and writing skills, and the ability to work well with others But those with the greatest competitive advantage also have strong technical training in the analytical and quantitative skills of management Modern finance theory emphasizes these skills It is to the students and faculty who seek to employ them that this textbook is addressed The six seminal and internally consistent theories upon which modern finance is founded are: (1) utility theory, (2) state-preference theory, (3) mean-variance theory and the capital asset pricing model, (4) arbitrage pricing theory, (5) option pricing theory, and (6) the Modigliani-Miller theorems They are discussed in Chapters through and in Chapter 13 Their common theme is "How individuals and society allocate scarce resources through a price system based on the valuation of risky assets?" Utility theory establishes the basis of rational decision making in the face of risky alternatives It focuses on the question "How people make choices?" The objects of choice are described by state-preference theory, mean-variance portfolio theory, arbitrage pricing, and option pricing theory When we combine the theory of choice with the objects of choice, we are able to determine how risky alternatives are valued When correctly assigned, asset prices provide useful signals to the economy for the necessary task of resource allocation Finally, the Modigliani-Miller theory asks the question "Does the method of financing have any effect on the value of assets, particularly the firm?" The answer to this question has important implications for the firm's choice of capital structure (debt-to-equity mix) and dividend policy It is important to keep in mind that what counts for a positive science is the development of theories that yield valid and meaningful predictions about observed phenomena The critical first test is whether the hypothesis is consistent with the evidence at hand Further testing involves deducing new facts capable of being observed but not previously known, then checking those deduced facts against additional empirical evidence As students of finance, we must not only understand the theory, but also review the empirical evidence to determine which hypotheses have been validated Consequently, every effort has been made to summarize the empirical evidence related to the theory of finance Chapter discusses empirical evidence on the capital asset pricing model and the arbitrage pricing theory Chapter includes studies of how alternative option pricing models perform Chapter 9, newly added to this edition, discusses the theory and evidence on futures markets Chapter 11 covers evidence on the efficient markets hypothesis Chapter 14 reviews evidence on capital structure; Chapter 16 on dividend policy; Chapter 20 on mergers and acquisitions; and Chapter 22 on international finance Finally, in addition to the theory and empirical evidence there is always the PREFACE V practical question of how to apply the concepts to difficult and complex realworld problems Toward this end, Chapters and are devoted to capital budgeting, Chapter 14 shows how to estimate the cost of capital for a large, publicly held corporation, and Chapter 16 determines the value of the same company Chapter 18, another change in this edition, emphasizes the theory and evidence on topics of interest to chief financial officers: pension fund management, interest rate swaps, and leveraged buyouts Throughout the text we attempt, wherever feasible, to give examples of how to apply the theory Among other things we show how the reader can estimate his or her own utility function, calculate portfolio means and variances, set up a cross-hedge to reduce the variance of equity returns, value a call option, determine the terms of a merger or acquisition, use international exchange rate relationships In sum, we believe that a sound foundation in finance theory requires not only a complete presentation of the theoretical concepts, but also a review of the empirical evidence that either supports or refutes the theory as well as enough examples to allow the practitioner to apply the validated theory B CHANGES IN THE THIRD EDITION We have tried to move all the central paradigms of finance theory into the first half of the book In the second edition this motivated our shifting the option pricing material into Chapter In this third edition we decided to add a completely new chapter on futures markets—Chapter It covers traditional material on pricing both commodity and financial futures, as well as newer issues: why futures markets exist, why there are price limits in some markets but not others, and empirical evidence on normal backwardation and contango In the materials on portfolio theory we have added a section on how to use T-bond futures contracts for cross-hedging In Chapter we have updated the literature review on the Capital Asset Pricing Model and the Arbitrage Pricing Model Chapter contains new evidence on option pricing The materials on capital structure (Chapters 13 and 14) and on dividend policy (Chapters 15 and 16) have been completely rewritten to summarize the latest thinking in these rapidly changing areas of research Chapter 18 is completely new Many topics of importance to chief financial officers are applications of finance theory Pension fund management, interest rate swaps, and leveraged buyouts are the examples developed in this chapter Chapters 19 and 20 on mergers and acquisitions, restructuring, and corporate control represent up-to-date coverage of the burgeoning literature Similarly, Chapters 21 and 22 reflect the latest thinking in the field of international financial management We made numerous other minor changes In general, we sought to reflect all of the new important literature of finance theory—published articles and treatises as well as working papers Our aim was to keep the book as close as possible to the frontiers of the "state-of-the-art" in the literature of finance theory Vi PREFACE C SUGGESTED USE IN CURRICULUM At UCLA we use the text as a second course in finance for MBA students and as the first finance course for doctoral students We found that requiring all finance majors to take a theory-of-finance course before proceeding to upperlevel courses eliminated a great deal of redundancy For example, a portfolio theory course that uses the theory of finance as a prerequisite does not have to waste time with the fundamentals Instead, after a brief review, most of the course can be devoted to more recent developments and applications Because finance theory has developed into a cohesive body of knowledge, it underlies almost all of what had formerly been thought of as disparate topics The theory of finance, as presented in this text, is prerequisite to security analysis, portfolio theory, money and capital markets, commercial banking, speculative markets, investment banking, international finance, insurance, case courses in corporation finance, and quantitative methods of finance The theory of finance can be, and is, applied in all of these courses That is why, at UCLA at least, we have made it a prerequisite to all the aforementioned course offerings The basic building blocks that will lead to the most advantageous use of this text include algebra and elementary calculus; basic finance skills such as discounting, the use of cash flows, pro-forma income statements and balance sheets; elementary statistics; and an intermediate-level microeconomics course Consequently, the book would be applicable as a second semester (or quarter) in finance This could occur at the junior or senior undergraduate year, for MBAs during the end of their first year or beginning of their second year, or as an introductory course for Ph.D students D USE OF THE SOLUTIONS MANUAL The end-of-chapter problems and questions ask the students not only to feed back what they have just learned, but also to take the concepts and extend them beyond the material covered directly in the body of the text Consequently, we hope that the solutions manual will be employed almost as if it were a supplementary text It should not be locked up in the faculty member's office, as so many instructor's manuals are It is not an instructor's manual in a narrow sense Rather, it is a solutions manual, intended for use by the students Anyone (without restriction) can order it from the publisher We order it, through our bookstore, as a recommended supplemental reading Understanding of the theory is increased by efforts to apply it Consequently, most of the end-of-chapter problems are oriented toward applications of the theory They require analytical thinking as well as a thorough understanding of the theory If the solutions manual is used, as we hope it will be, then students who learn how to apply their understanding of the theory to the end-of-chapter problems will at the same time be learning how to apply the theory to real-world tasks PREFACE Vii E ACKNOWLEDGMENTS We have received help from many persons on the three editions of the book We especially benefited from the insightful corrections, clarifications, and suggestions of Eugene Fama, Herb Johnson, and Kuldeep Shastri Nai-fu Chen and Ronald Bibb wrote Appendixes B and D, respectively Ron Masulis rewrote Chapter We also wish to acknowledge the help of the following: Ed Altman, Enrique Arzac, Dan Asquith, Warren Bailey, Gerry Bierwag, Diran Bodenhorn, Jim Brandon, Michael Brennan, William Carleton, Don Chance, Nai-fu Chen, Don Chew, Kwang S Chung, Halimah Clark, Peter Clark, S Kerry Cooper, Larry Dann, Harry and Linda E DeAngelo, Dirk Davidson, David Eiteman, Chapman Findlay, Kenneth French, Dan Galai, Robert Geske, Mark Grinblatt, C W Haley, Ronald Hanoian, Iraj Heravi, David Hirshleifer, Tom Ho, Chi-Cheng Hsia, William C Hunter, Ashok Korwar, Clement Krouse, Steven Lippman, Stephen Magee, Dubos Masson, Bill Margrabe, Charles Martin, Ronald Masulis, David Mayers, Guy Mercier, Edward Miller, Merton Miller, Timothy J Nantell, Ron Necoechea, Jorge:Nielson, R Richardson Pettit, Richard Pettway, Richard Roll, Shigeki Sakakibara, Eduardo Schwartz, Jim Scott, Jandhyala Sharma, Kilman Shin, Ron Shrieves-, Keith Smith, Dennis Soter, Joel Stern, Sheridan Titman, Brett Trueman, Jim Wansley, Marty Weingartner, Richard West, Randy Westerfield, Robert Whaley, Stuart Wood, and Bill Ziemba For their considerable help in preparation of the text, we thank Susan Hoag and Marilyn McElroy We also express appreciation for the cooperation of the Addison-Wesley staff: Steve Mautner, Herb Merritt, and their associates There are undoubtedly errors in the final product, both typographical and conceptual as well as differences of opinion We invite readers to send suggestions, comments, criticisms, and corrections to the authors at the Anderson Graduate School of Management, University of California, Los Angeles, CA 90024 Any form of communication will be welcome Los Angeles, California T.E.C J.F.W Contents PART I THE THEORY OF FINANCE 1 Introduction: Capital Markets, Consumption, and Investment Introduction Consumption and Investment without Capital Markets Consumption and Investment with Capital Markets Marketplaces and Transactions Costs 13 Transactions Costs and the Breakdown of Separation 14 Summary 15 Problem Set 15 References 16 Investment Decisions: The Certainty Case Introduction 17 Fisher Separation 18 The Agency Problem 20 Maximization of Shareholders' Wealth 20 Techniques for Capital Budgeting 25 Comparison of Net Present Value with Internal Rate of Return 31 Cash Flows for Capital Budgeting Purposes 36 Summary and Conclusion 41 Problem Set 41 References 44 More Advanced Capital Budgeting Topics Introduction 46 Capital Budgeting Techniques in Practice 47 Projects with Different Lives 49 Constrained Capital Budgeting Problems 55 Capital Budgeting Procedures under Inflation 61 46 The Term Structure of Interest Rates 65 Summary and Conclusions 71 Problem Set 72 References 74 The Theory of Choice: Utility Theory Given Uncertainty Five Axioms of Choice under Uncertainty 79 Developing Utility Functions 80 Establishing a Definition of Risk Aversion 85 17 77 Comparison of Risk Aversion in the Small and in the Large 90 Stochastic Dominance 92 Using Mean and Variance as Choice Criteria 96 ix X CONTENTS A Mean-Variance Paradox 99 Recent Thinking and Empirical Evidence 102 Summary 103 Problem Set 103 References 107 State-Preference Theory Uncertainty and Alternative Future States 110 Definition of Pure Securities 111 Complete Capital Market 111 Derivation of Pure Security Prices 113 No Arbitrage Profit Condition 115 Economic Determinants of Security Prices 116 Optimal Portfolio Decisions 119 Portfolio Optimality Conditions and Portfolio Separation 122 Firm Valuation, the Fisher Separation Principle, and Optimal Investment Decisions 124 109 Summary 128 Problem Set 129 References 131 Appendix A to Chapter 5: Forming a Portfolio of Pure Securities 133 Appendix B to Chapter 5: Use of Prices for State-Contingent Claims in Capital Budgeting 135 Appendix C to Chapter 5: Application of the SPM in Capital Structure Decisions 140 Objects of Choice: Mean-Variance Uncertainty Measuring Risk and Return for a Single Asset 146 Measuring Portfolio Risk and Return 153 Optimal Portfolio Choice: The Efficient Set with Two Risky Assets (and No Risk-Free Asset) 166 The Efficient Set with One Risky and One Risk-Free Asset 171 Optimal Portfolio Choice: Many Assets 173 Portfolio Diversification and Individual Asset Risk 184 Summary 188 Problem Set 188 References 192 Market Equilibrium: CAPM and APT Introduction 193 The Efficiency of the Market Portfolio 194 Derivation of the CAPM 195 Properties of the CAPM 198 Use of the CAPM for Valuation: SinglePeriod Models, Uncertainty 202 Applications of the CAPM for Corporate Policy 204 Extensions of the CAPM 205 193 Empirical Tests of the CAPM 212 The Problem of Measuring Performance: Roll's Critique 217 The Arbitrage Pricing Theory 219 Empirical Tests of the Arbitrage Pricing Theory 228 Summary 231 Problem Set 231 References 235 Pricing Contingent Claims: Option Pricing Theory and Evidence Introduction 240 A Description of the Factors That Affect Prices of European Options 241 145 Combining Options, A Graphic Presentation 245 Equity as a Call Option 248 240 342 EFFICIENT CAPITAL MARKETS: THEORY Table 10.4 Parameters for an Experimental Double Auction Futures Market Investor Type Initial Working Capital Initial Shares Held Fixed Cost Period A Period B I II III 15,000 francs 15,000 francs 15,000 francs shares shares shares 15,500 francs 15,500 francs 15,500 francs 403 284 110 146 372 442 Dividends (francs) value is really 300 francs Obviously they not know this during the first trial of the experiment, but they learn quickly If instead bidding had taken place in both period A and B markets simultaneously, perhaps the speed of adjustment to a rational expectations equilibrium would have been faster In another experiment, Forsythe, Palfrey, and Plott [1982] opened a futures market Everything remained the same as before except bidding for period B holdings was held concurrently with the period A spot market, and the payoffs were as shown in Table 10.4 The rational expectations hypothesis predicts that the period A price will be 845 francs, whereas the intrinsic value hypothesis predicts 403 francs They both predict a period B price of 442 francs The results are shown in Fig 10.4 Even in the first trial, the period A spot price closed at 742 francs, much closer to the rational expectations prediction In subsequent trials ("years") the closing prices were even closer to the results predicted by the rational expectations hypothesis Perhaps the Year 9_ Price 950 A 850 750 B A Year S i .:•• B A B _ _ - B A _ • A „ - I A B B - _I -I 650 550 450 -._ ••• -•• 1— _ pE B - 350 250 742 371 806 425 800 429 825 435 Average price 831 435 31 437 period period spot B futures Figure 10.4 Rational expectations with a futures market (From R Forsythe, T Palfrey, and C R Plott, "Asset Valuation in an Experimental Market," reprinted from Econometrica, May 1982, 554.) MARKET EFFICIENCY WITH COSTLY INFORMATION 343 most valuable implication of the experiment is that it clearly demonstrates the usefulness of futures markets By allowing simultaneous trading in both markets, the speed with which information is made public is increased through price transactions Information about the future value of assets is revealed today In the rational expectations equilibria described above, all traders knew with certainty what their own payoffs would be in each time period but did not know the asset clearing price because other individuals had different payoffs in the same state of nature These different payoffs represent a form of heterogeneous expectations In the above experiments all market participants were equally well informed There is a different way of looking at heterogeneous expectations, however Suppose that some traders are better informed about which states of nature will actually occur Furthermore, suppose that different individuals have different information about which states will occur For example, suppose investor I knows for sure that a Republican will be elected president but knows nothing else Investor J, on the other hand, knows that both houses of Congress will be Democratic but knows nothing else The question is this: Will market prices reflect the full impact of both pieces of information as though the market were fully informed, or will prices reflect only some average of the impact of both pieces of information? If prices reflect all information, the market is said to be fully aggregating; otherwise it is only averaging prices Very little is known about whether real-world capital markets fully aggregate information or merely average it A fully aggregating market, however, would be consistent with Fama's [1970] definition of strong-form market efficiency In a fully aggregating market even insiders who possess private information would not be able to profit by it One mechanism for aggregation has been suggested by Grossman and Stiglitz [1976] and Grossman [1976] In a market with two types of traders, "informed" and "uninformed," informed traders will acquire better estimates of future states of nature and take trading positions based on this information When all informed traders this, current prices are affected Uninformed traders invest no resources in collecting information, but they can infer the information of informed traders by observing what happens to prices Thus the market prices may aggregate information so that all traders (both informed and uninformed) become informed In Chapter 11 we will suggest that capital markets not instantaneously and fully aggregate information because empirical evidence on insider trading reveals that insiders can and make abnormal returns E MARKET EFFICIENCY WITH COSTLY INFORMATION If capital markets are efficient, then no one can earn abnormal returns, but without abnormal returns there is no strong incentive to acquire information Random selection of securities is just as effective How, then, can prices reflect information if there Actually, this idea can be traced back to Hayek's classic article, "The Use of Knowledge in Society" [1945] 344 EFFICIENT CAPITAL MARKETS: THEORY Table 10.5 Net Payoffs, Given Costly Information His Opponent Analyzes? Yes No The Trader Yes Analyzes? No r — c, = —2% rid—c =-1i dr — c, = 4% r — c, = 2% r = normal return = 6% d = competitive advantage = x c2 = cost of analysis = 8% c = cost with no analysis = 4% is no incentive to search it out and use it for arbitrage? How can a securities analysis industry exist? The above argument may have some merit in a world with costless information because all investors would have zero abnormal returns.' However, it is probably premature to predict the demise of the security analysis industry or to argue that prices are uninformative Grossman and Stiglitz [1976, 1980] and Cornell and Roll [1981] have shown that a sensible asset market equilibrium must leave some room for analysis Their articles make the more reasonable assumption that information acquisition is a costly activity Because of its simplicity, the Cornell and Roll model is discussed below We want to analyze the rational behavior of individuals when information is useful in the sense that having it will improve one's decisions but also where information is costly Imagine two simple strategies The first is to pay a fee, say c = 8%, for acquiring valuable information This is called the analyst strategy The opposing strategy is to pay a minimal fee, say c = 4%, for the right to trade Call this the random selector's strategy Table 10.5 shows the net payoffs for various twoway trades involving all combinations of analysts and random selectors Note that the "normal" rate of return, r, is 6% (c < r < c 2) The example in Table 10.5 assumes that the costly information doubles the competitive advantage, d, of an analyst whenever he or she trades with a random selector The analyst, being better informed, grosses 12% and nets 4% after paying 8% for the information Conversely, the random selector finds his or her gross return halved when trading with an analyst He or she grosses only 3% and nets —1% after paying 4% on transactions costs When an analyst trades with another analyst there is no competitive advantage because they possess the same information Thus their gross return is only 6% and they net —2% A stable equilibrium can exist (1) if all trading is anonymous and (2) if the expected payoff to the analysis strategy equals the expected payoff to the random 10 selection strategy If p is the probability of utilizing an analyst's strategy and Abnormal returns are returns in excess of what can be earned for a given level of risk Anonymous trading is necessary so that uninformed random selectors will actually consummate a trade with an analyst with superior information One service provided by brokers is to ensure the anonymity of their clients 19 MARKET EFFICIENCY WITH COSTLY INFORMATION 345 — p is the probability of random selection, then the equilibrium condition is E(Payoff to analysis strategy) = E(Payoff to random selection) p(r — c ) + (1 — p)(dr — c ) = p(r/d — c ) + (1 — p)(r — c ) (10.4) The expected payoff to analysis [the left-hand side of Eq (10.4)] is the probability that an analyst will confront another analyst multiplied by the net payoff given this event, plus the probability of confronting a random selector multiplied by the net payoff in that event Similar logic produces the expected payoff for a random selector [the right-hand side of Eq (10.4)] Solving Eq (10.4) for p, the probability of using analysis, we have P= r(1 — d) + c — c (10.5) 2r — rd — r/d A mixed stable strategy is one where < p < 1, that is, where analysts and random selectors will coexist in equilibrium The necessary conditions for a mixed stable strategy are r(d — 1) > c — c and r(1 — 1/d) < c, — c (10.6) These conditions can be derived from the definition of the equilibrium probability, p, Eq (10.5) We know that the "normal" rate of return, r, is greater than zero and the competitive advantage, d, is greater than one Therefore the denominator of Eq (10.5), must be negative: 2r — rd — r/d < 0, 2d — d — < 0, (d — 1) > 0, since d > QED It follows that the numerator of Eq (10.5) must also be negative if the probability, p, is to be positive Therefore r(1 — d) + c — c < 0, r(d — 1) > c — c 1, and we have derived the first necessary condition in Eq (10.6) Also, in order for p < the numerator of Eq (10.5) must be greater than the denominator (since both are negative numbers) This fact gives us the second necessary condition: r(1 — d) c — c, > 2r — rd — r/d, c — c > r(1 — 1/d) If there is no net economic profit when the mixed stable strategy evolves, then there will be no incentive for new entrants to disturb the equilibrium This zero profit condition is equivalent to setting both sides of Eq (10.4), the expected payoff equation, equal to zero This results in two equations, which when equated and simplified 346 EFFICIENT CAPITAL MARKETS: THEORY give the further result that d = c 2/c and p = (rd — c )/(rd — r) for a stable mixed strategy where all net profits are zero Using the numbers in Table 10.5, we see that a stable mixed strategy with p = will exist Thus with costly information we will observe the analyst strategy being used two thirds and the random selection strategy one third of the time No one will be tempted to change strategies because there is no incentive to so Also, we will observe that the gross return for analysis is higher than for random selection But once the cost of obtaining information is subtracted the net rate of return to both strategies is the same The simple model of Cornell and Roll [1981] shows that there is nothing inconsistent about having efficient markets and security analysis at the same time The average individual who utilizes costly information to perform security analysis will outperform other individuals who use less information, but only in terms of gross returns The net return to both strategies will be identical Some empirical evidence consistent with this point of view is presented in Chapter 11 where mutual fund performance is discussed F STATISTICAL TESTS UNADJUSTED FOR RISK Historically it was possible to test certain predictions of the efficient markets hypothesis even before a theory of risk-bearing allowed comparison of risk-adjusted returns For example, if the riskiness of an asset does not change over time or if its risk changes randomly over time, then there should be no pattern in the time series of security returns If there were a recurring pattern of any type, investors who recognize it could use it to predict future returns and make excess profits However, in their very efforts to use the patterns, they would eliminate them Three theories of the time series behavior of prices can be found in the literature: (1) the fair-game model, (2) the martingale or submartingale, and (3) the random walk The fair game model is based on the behavior of average returns (not on the entire probability distribution) Its mathematical expression is ei,t+ = Pi,t+i Pit E(Pi,t+) TO Pit Pit P j,t +1 — E( 13 J,t + Pit where = the actual price of security j next period, E(PJ,t+1 th)= the predicted end-of-period price of security j given the current information structure, u„ the difference between actual and predicted returns , = ei ,t+ (10.7) STATISTICAL TESTS UNADJUSTED FOR RISK 347 Note that (10.7) is really written in returns form If we let the one-period return be defined as r+1= P j,t + — P jt Pit then (10.7) may be rewritten as = rj,t+ E(ri,t+ 1111t) and E(e1,t+1) = E[ri,t+1 — E(rj,t +1 nt)] = (10.8) A fair game means that, on average, across a large number of samples the expected return on an asset equals its actual return An example of a fair game would be games of chance in Las Vegas Because of the house percentage, you should expect to lose, let us say, 10%; and sure enough, on the average that is what people actually lose A fair game does not imply that you will earn a positive return; only that expectations are not biased Given the definition of a fair game in Eq (10.7), a submartingale is a fair game where tomorrow's price is expected to be greater than today's price Mathematically, a submartingale is > Pit In returns form this implies that expected returns are positive This may be written as follows: E(P + t) = E(ri,t+11111) > Pit (10.9a) A martingale is also a fair game With a martingale, however, tomorrow's price is expected to be the same as today's price Mathematically, this is E(Pi,t +1 = Pit, or in returns form, it is written as E(Pi,t+1 ir/) Pft — Pit = r, E4r = O (10.9b) A submartingale has the following empirical implication: Because prices are expected to increase over time, any test of the abnormal return from an experimental portfolio must compare its return from a buy-and-hold strategy for a control portfolio of the same composition If the market is an efficient submartingale, both portfolios will have a positive return, and the difference between their returns will be zero In other words, we will observe a fair game with positive returns: a submartingale Finally, a random walk says that there is no difference between the distribution of returns conditional on a given information structure and the unconditional distribution of returns Equation (10.2) is a random walk in prices Equation (10.10) is a random walk in returns: f(ri,t+ rn,t+ 1) = f(ri,t+ rn,t+ ant) (10.10) 348 EFFICIENT CAPITAL MARKETS: THEORY Random walks are much stronger conditions than fair games or martingales because they require all the parameters of a distribution (e.g., mean, variance, skewness, and kurtosis) to be the same with or without an information structure Furthermore, successive drawings over time must (1) be independent and (2) be taken from the same distribution If returns follow a random walk, then the mean of the underlying distribution does not change over time, and a fair game will result Most empirical evidence indicates that security returns not follow a process that has all the properties of a random walk This makes sense because the condition that the entire underlying probability distribution of returns remain stationary through time is simply too strong It is reasonable to believe that because of changes in the risk of a firm, the variance of stock returns will change over time This, in fact, appears to be the case The fair-game model makes no statement about the variance of the distribution of security returns, and consequently, the nonstationarity of return variances is irrelevant to its validity." A statistical difference between fair games and random walks is that the latter hypothesis requires that all drawings be independently taken from the same distribution, whereas the former does not This means that the random walk requires that serial covariances between returns for any lag must be zero However, significant serial covariances of one-period returns are not inconsistent with a fair game To see this, suppose that the relevant information structure consists of past returns In other words, assume weak-form market efficiency When Eq (10.7) is written in returns form, we have Ej,t+ = Ej,t+ — E(rj,,± I'm + 1, • • • (10.11) and gei,t+i) = O Note that the fair game variable, Ei ,t+ ,, is the deviation of the return in period t + from its conditional expectation, i.e., the residual If the residual is a fair game, then it must have zero serial covariance for all lags Yet even though the residual is a fair game variable, the conditional expectation of returns for t + can depend on the return observed for t Therefore the serial covariances of returns need not be zero The serial covariance for one-period returns is12 E[(r j ,t+ , — E(r j ,t+ ,))(r it — E(r jt ))] = COV(r j ,, ± r jt ) = f — E(r j ,)][r j ,t+ , — E(r j ,t+ ,)]f(r it ) dr it 11 For example, consider a situation where random drawings are taken randomly from two normal distributions that have a mean return of zero but different return variances The expected value of a large sample of alternative drawings would be zero; therefore we have a fair game However, the experiment violates the random walk requirement that all drawings be taken from the same distribution 12 The reader who is unfamiliar with covariances is referred to Chapter In general the covariance between two random variables, x and y, is COV(x, y) = E[(x — E(x))(y — E(y))] STATISTICAL TESTS UNADJUSTED FOR RISK 349 From (10.11) we know that E[ri,,,_,Irid] = r1,,,, Therefore ri1) = frit [r j, — E(r1 )][E(ri,, ,,1rit) E(ri,,,,)]f(rit )drit (10.13) But the fair game in residuals, Eq (10.11), does not imply that E(ri,, ±1 vit) = We have the result that the deviation of return for t from its conditional expectation is a fair game, but the conditional expectation of return itself can depend on the return observed for t Therefore serial covariances of one-period returns are not inconsistent with a fair game model However, they are inconsistent with a random walk because the latter requires that successive drawings be independent (a serial covariance of zero for all lags) Fama [1965] has presented evidence to show that the serial correlations of oneday changes in the natural logarithm of price are significantly different from zero for 11 out of 30 of the Dow Jones Industrials.' Furthermore, 22 of the 30 estimated serial correlations are positive This, as well as evidence collected by other authors, shows that security returns are not, strictly speaking, random walks However, the evidence is not inconsistent with fair-game models or, in particular, the submartingale Direct tests of the fair-game model were provided by Alexander [1961] and Fama and Blume [1966] They used a technical trading filter rule, which states: Using price history, buy a stock if the price rises x%, hold it until the security falls x%, then sell and go short Maintain the short position until the price rises x%, then cover the short position and establish a long position This process is repeated for a fixed time interval, and the performance according to the filter rule is then compared with a buy-and-hold strategy in the same security Because each security is compared with itself, there is no need to adjust for risk Filter rules are designed to make the investor a profit if there are any systematic patterns in the movement of prices over time It is only a matter of trying enough different filters so that one of them picks up any serial dependencies in prices and makes a profit that exceeds the simple buy-and-hold strategy The filter rule tests have three important results First, they show that even before subtracting transactions costs, filters greater than 1.5% cannot beat a simple buyand-hold strategy Second, filters below 1.5%, on the average, make very small profits that because of frequent trading can beat the market This is evidence of a very shortterm serial dependence in price changes However, it is not necessarily evidence of capital market inefficiency First one must subtract from gross profits the cost of taking action based on the filter rule Fama and Blume [1966] show that even a floor trader (the owner of a seat on the NYSE) must pay at least 1% per transaction Once these costs are deducted from the profits of filters that are less than 1.5%, the profits vanish Therefore the capital market is allocationally efficient down to the To show that the logarithm of successive price changes is a good approximation of returns, assume one-period continuous compounding: 13 Pt+ I = Pt e", P — In Pt+ — In P, = t+ P, where t = 1, P, , where r=P —P P, 350 EFFICIENT CAPITAL MARKETS: THEORY level of transactions costs The smaller the transactions costs are, the more operationally efficient the market is, and smaller price dependencies are eliminated by arbitrage trading Capital markets are efficient in their weak form because the return on a portfolio managed with price-history information is the same as a buy-and-hold strategy that uses no information Therefore the value of messages provided by filter rules is zero Technical trading does not work." The third inference that can be drawn from filter tests is that the market appears to follow a submartingale All the securities tested had average positive returns This makes sense because risky assets are expected to yield positive returns to compensate investors for the risk they undertake G THE JOINT HYPOTHESIS OF MARKET EFFICIENCY AND THE CAPM Statistical tests and filter rules are interesting and present evidence of weak-form efficiency but are limited by the fact that they cannot compare assets of different risk The CAPM provides a theory that allows the expected return of a fair-game model to be conditional on a relevant costless measure of risk." If the CAPM is written as a fair game, we have ejt = Rjt Pjt) = R t E(eit) = 0, E (Rjt jt), [ E(Rmtl amt) R ft]fi 5, (10.14) (10.15) where E(Rit l it) = the expected rate of return on the jth asset during this time period, given a prediction of its systematic risk, flit, R 1, = the risk-free rate of return during this time period, E(R,„1 Ant) = the expected market rate of return, given a prediction of its systematic risk, 13m1' = the estimated systematic risk of the jth security based on last time period's information structure lit _ t The CAPM is graphed in Fig 10.5 According to the theory, the only relevant parameter necessary to evaluate the expected return for every security is its systematic risk." Therefore if the CAPM is true and if markets are efficient, the expected return of every asset should fall exactly on the security market line Any deviation from the See Ball [1978] for a discussion of filter rules and how to improve them as tests of market efficiency Note that the discussion that follows also applies the arbitrage pricing theory if one allows the expected return to depend on multiple factor loadings (i.e., multiple betas) " For a detailed explanation of the CAPM and empirical tests of it, see Chapter 14 15 THE JOINT HYPOTHESIS OF MARKET EFFICIENCY AND THE CAPM 351 E(Rit ) Figure 10.5 The CAPM as a fair game expected return is interpreted as an abnormal return, eft , and can be taken as evidence of market inefficiency if the CAPM is correct The CAPM is derived from a set of assumptions that are very similar to those of market efficiency For example, the Sharpe-Lintner-Mossin derivation of the CAPM assumes: • All investors are single-period expected utility of wealth maximizers whose utility functions are based on the mean and variance of return • All investors can borrow or lend an indefinite amount at the risk-free rate, and there are no restrictions on short sales • All investors have homogeneous expectations of the end-of-period joint distributions of returns • Securities markets are frictionless and perfectly competitive In Chapter 11 we shall report the results of several empirical studies that use the CAPM as a tool for analyzing capital market efficiency However, one should always keep in mind the fact that the CAPM and capital market efficiency are joint and inseparable hypotheses If capital markets are inefficient, then the assumptions of the CAPM are invalid and a different model is required And if the CAPM is inappropriate, even though capital markets are efficient, then the CAPM is the wrong tool to use in order to test for efficiency Various sophisticated empirical tests of the CAPM by Black, Jensen, and Scholes [1972], Black and Scholes [1974], and Fama and MacBeth [1973] show that the CAPM fits reality surprisingly well However, because the theoretical CAPM assumes market efficiency, any empirical results that show that on the average there are no significant deviations from the model are merely consistent with market efficiency They not necessarily prove market efficiency because the model might be wrong Therefore any test of market efficiency that uses the CAPM to adjust for risk is, as mentioned before, a joint test of the CAPM that assumes market efficiency for its derivation and of market efficiency itself 352 EFFICIENT CAPITAL MARKETS: THEORY One may also ask the question: "If I can accurately predict systematic risk, 13;t, I can also predict the expected rate of return on an asset; doesn't this mean that I can beat the market?" The answer, of course, is: "Probably not." If the information necessary to estimate is publicly available and if markets are efficient in their semistrong form, then prices will instantaneously and fully reflect all the information relevant for estimating flit, the expected return of the security will fall exactly on the security line, and no abnormal returns will be observed Perhaps the most interesting use of the CAPM is to examine historical situations to see whether or not the market was efficient for a particular set of information If the CAPM is valid (we shall assume it is, but keep in mind that it is a joint hypothesis with market efficiency), then any evidence of persistent deviations from the security market line can be interpreted as evidence of capital market inefficiency with regard to a particular information set Chapter 11 is devoted to tests of market efficiency with regard to various information sets SUMMARY The hypothesis of capital market efficiency has attracted a great deal of interest and critical comment This is somewhat surprising because capital market efficiency is a fairly limited concept It says that the prices of securities instantaneously and fully reflect all available relevant information It does not imply that product markets are perfectly competitive or that information is costless Capital market efficiency relies on the ability of arbitrageurs to recognize that prices are out of line and to make a profit by driving them back to an equilibrium value consistent with available information Given this type of behavioral paradigm, one often hears the following questions: If capital market efficiency implies that no one can beat the market (i.e., make an abnormal profit), then how can analysts be expected to exist since they, too, cannot beat the market? If capital markets are efficient, how can we explain the existence of a multibillion dollar security analysis industry? The answer, of course, is that neither of these questions is inconsistent with efficient capital markets First, analysts can and make profits However, they compete with each other to so If the profit to analysis becomes abnormally large, then new individuals will enter the analysis business until, on average, the return from analysis equals the cost (which, by the way, includes a fair return to the resources that are employed) As shown by Cornell and Roll [1981], it is reasonable to have efficient markets where people earn different gross rates of return because they pay differing costs for information However, net of costs their abnormal rates of return will be equal (to zero) As we shall see in the next chapter, the concept of capital market efficiency is important in a wide range of applied topics, such as accounting information, new issues of securities, and portfolio performance measurement By and large the evidence seems to indicate that capital markets are efficient in the weak and semistrong forms but not in the strong form PROBLEM SET 353 PROBLEM SET 10.1 Suppose you know with certainty that the Clark Capital Corporation will pay a dividend of $10 per share on every January forever The continuously compounded risk-free rate is 5% (also forever) a) Graph the price path of the Clark Capital common stock over time b) Is this (highly artificial) example a random walk? A martingale? A submartingale? (Why?) 10.2 Given the following situations, determine in each case whether or not the hypothesis of an efficient capital market (semistrong form) is contradicted a) Through the introduction of a complex computer program into the analysis of past stock price changes, a brokerage firm is able to predict price movements well enough to earn a consistent 3% profit, adjusted for risk, above normal market returns b) On the average, investors in the stock market this year are expected to earn a positive return (profit) on their investment Some investors will earn considerably more than others c) You have discovered that the square root of any given stock price multiplied by the day of the month provides an indication of the direction in price movement of that particular stock with a probability of d) A Securities and Exchange Commission (SEC) suit was filed against Texas Gulf Sulphur Company in 1965 because its corporate employees had made unusually high profits on company stock that they had purchased after exploratory drilling had started in Ontario (in 1959) and before stock prices rose dramatically (in 1964) with the announcement of the discovery of large mineral deposits in Ontario 10.3 The First National Bank has been losing money on automobile consumer loans and is considering the implementation of a new loan procedure that requires a credit check on loan applicants Experience indicates that 82% of the loans were paid off, whereas the remainder defaulted However, if the credit check is run, the probabilities can be revised as follows: Loan is paid Loan is defaulted Favorable Credit Check Unfavorable Credit Check 5 An estimated 80% of the loan applicants receive a favorable credit check Assume that the bank earns 18% on successful loans, loses 100% on defaulted loans, suffers an opportunity cost of 18% when the loan is not granted but would have been successful, and an opportunity cost of 0% when the loan is not granted and would have defaulted If the cost of a credit check is 5% of the value of the loan and the bank is risk neutral, should the bank go ahead with the new policy? 10.4 Hearty Western Foods, one of the nation's largest consumer products firms, is trying to decide whether it should spend $5 million to test market a new ready-to-eat product (called Kidwich), to proceed directly to a nationwide marketing effort, or to cancel the product The expected payoffs (in millions of dollars) from cancellation vs nationwide marketing are given 354 EFFICIENT CAPITAL MARKETS: THEORY below: Action Market Conditions Cancel Go Nationwide No acceptance Marginal Success 0 —10 10 80 Prior experience with nationwide marketing efforts has been: Market Conditions Probability No acceptance Marginal Success If the firm decides to test market the product, the following information will become available: Probability Outcome Predicted by the Test Market No Acceptance Marginal Success 1 No Acceptance Marginal Success For example, if the test market results predict a success, there is a 60% chance that the nationwide marketing effort really will be a success but a 30% chance it will be marginal and a 10% chance it will have no acceptance a) If the firm is risk neutral, should it test market the product or not? b) If the firm is risk averse with a utility function U(W)= In(W + 11), should it test market the product or not? 10.5 The efficient market hypothesis implies that abnormal returns are expected to be zero Yet in order for markets to be efficient, arbitrageurs must be able to force prices back into equilibrium If they earn profits in doing so, is this fact inconsistent with market efficiency? 10.6 a) In a poker game with six players, you can expect to lose 83% of the time How can this still be a martingale? b) In the options market, call options expire unexercised over 80% of the time." Thus the option holders frequently lose all their investment Does this imply that the options market is not a fair game? Not a martingale? Not a submartingale? 17 See Chapter for a description of call options REFERENCES 355 10.7 If securities markets are efficient, what is the NPV of any security, regardless of its risk? 10.8 From time to time the federal government considers passing into law an excess profits tax on U.S corporations Given what you know about efficient markets and the CAPM, how would you define excess profits? What would be the effect of an excess profits tax on the investor? 10.9 State the assumptions inherent in this statement: A condition for market efficiency is that there be no second-order stochastic dominance REFERENCES Alexander, S S., "Price Movements in Speculative Markets: Trends or Random Walks," Industrial Management Review, May 1961, 7-26 Ball, R., "Filter Rules: Interpretation of Market Efficiency, Experimental Problems and Australian Evidence," Accounting Education, November 1978, 1-17 Black, F.; M Jensen; and M Scholes, "The Capital Asset Pricing Model: Some Empirical Tests," in Jensen, ed., Studies in the Theory of Capital Markets Praeger, New York, 1972, 79-124 Black, F., and M Scholes, "The Effects of Dividend Yield and Dividend Policy on Common Stock Prices and Returns," Journal of Financial Economics, May 1974, 1-22 Copeland, T E., and D Friedman, "The Market for Information: Some Experimental Results," Working Paper 5-87, UCLA Graduate School of Management, 1986 Cornell, B., and R Roll, "Strategies for Pairwise Competitions in Markets and Organizations," Bell Journal of Economics, Spring 198.1, 201-213 Fama, E F., "The Behavior of Stock Market Prices," Journal of Business, January 1965, 34-105 , "Efficient Capital Markets: A Review of Theory and Empirical Work," Journal of Finance, May 1970, 383-417 , Foundations of Finance Basic Books, New York, 1976 , and M Blume, "Filter Rules and Stock Market Trading Profits," Journal of Business, January (spec supp.) 1966, 226-241 Fama, E F., and J MacBeth, "Risk, Return and Equilibrium: Empirical Test," Journal of Political Economy, May—June 1973, 607-636 Finnerty, J E., "Insiders and Market Efficiency," Journal of Finance, September 1976, 11411148 Forsythe, R.; T Palfrey; and C R Plott, "Asset Valuation in an Experimental Market," Econometrica, May 1982, 537-567 Green, J R., "Information, Efficiency and Equilibrium," Discussion Paper No 284, Harvard Institute of Economic Research, March 1974 Grossman, S J., "On the Efficiency of Competitive Stock Markets Where Trades Have Diverse Information," Journal of Finance, May 1976, 573-586 , and J Stiglitz, "Information and Competitive Price Systems," American Economic Review, May 1976, 246-253 , "The Impossibility of Informationally Efficient Markets," American Economic Review, June 1980, 393-408 356 EFFICIENT CAPITAL MARKETS: THEORY Harrison, J M., and D M Kreps, "Speculative Investor Behavior in a Stock Market with Heterogeneous Expectations," Quarterly Journal of Economics, May 1978, 323-336 Hayek, F H., "The Use of Knowledge in Society," American Economic Review, September 1945 Hirshleifer, J., Investment, Interest, and Capital Prentice-Hall, Englewood Cliffs, N.J., 1970 , and J Riley, "The Analytics of Uncertainty and Information—An Expository Survey," Journal of Economic Literature, December 1979, 1375-1421 Huang, C C.; I Vertinsky; and W T Ziemba, "Sharp Bounds on the Value of Perfect Information," Operations Research, January–February 1977, 128-139 Jaffe, J., "The Effect of Regulation Changes on Insider Trading," Bell Journal of Economics and Management Science, Spring 1974, 93-121 Keynes, J M., The General Theory of Employment, Interest and Money Harcourt Brace, New York, 1936 Latham, M., "Defining Capital Market Efficiency," Finance Working Paper 150, Institute for Business and Economic Research, University of California, Berkeley, April 1985 Lucas, R E., "Expectations and the Neutrality of Money," Journal of Economic Theory, April 1972, 103-124 Marschak, J., Economic Information, Decisions, and Predictions, Selected Essays, Vol Reidel, Boston, 1974 Miller, R M.; C R Plott; and V L Smith, "Intertemporal Competitive Equilibrium: An Empirical Study of Speculation," American Economic Review, June 1981, 448-459 Plott, C R., and S Sunder, "Efficiency of Experimental Security Markets with Insider Information: An Application of Rational Expectations Models," Journal of Political Economy, August 1982, 663-698 Rubinstein, M., "Securities Market Efficiency in an Arrow-Debreu Economy," American Economic Review, December 1975, 812-824 Samuelson, P A., "Proof that Properly Anticipated Prices Fluctuate Randomly," Industrial Management Review, Spring 1965, 41-49 Smith, V L., "Experimental Economics: Induced Value Theory," American Economic Review, May 1976, 274-279 Sunder, S., "Market for Information: Experimental Evidence," Working Paper, University of Minnesota, 1984 ... + Div, (1 + g) Div, (1 + g) Div 1( 1 + g) Div 1( 1 + g) + + ks (1 + IcY + (1 + ks) + (1 + kJ'' (1 ± V + S5 (1 + ks) 1. 00 1. 05 1. 10 1. 16 1. 22 25.52 + + + + + 1. 1 1. 21 1.33 1. 46 1. 61 1. 61 = 91 + 87... 800 13 8.80 640 17 3.70 512 19 2.80 410 502.50 328 91. 13 PV at 22.8% -10 00.00 1. 000 80.00 814 12 8.00 663 15 3.60 540 16 3.84 440 410 .00 358 -64.56 10 00.00 81. 40 13 2.60 16 2.00 17 6.00 447.50 -.50 We... for IRR: NPV = = 0= ? ?1, 600 10 ,000 ? ?10 ,000 + + (1 + IRR)° (1 + IRR) (1 + IRR)2 '' ? ?1, 600 (1 + IRR)2 + 10 ,000 (1 + IRR) — 10 ,000 (1 + IRR)2 = 1, 600 (1 + IRR)2 — 10 ,000 (1 + IRR) + 10 ,000 This is clearly