公司理財(cái)精要版原書(shū)第12版英文版課件Ross-12e-Ch13

1、CHAPTER 13RETURN, RISK, AND THE SECURITY MARKET LINECopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.CHAPTER 13RETURN, RISK, AND THShow how to calculate expected returns, variance, and standard deviat

2、ionDiscuss the impact of diversificationSummarize the systematic risk principleDescribe the security market line and the risk-return trade-offKey Concepts and SkillsCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-H

3、ill Education.Show how to calculate expectedExpected Returns and VariancesPortfoliosAnnouncements, Surprises, and Expected ReturnsRisk: Systematic and UnsystematicDiversification and Portfolio RiskSystematic Risk and BetaThe Security Market LineThe SML and the Cost of Capital: A PreviewChapter Outli

4、neCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Expected Returns and VariancesExpected returns are based on the probabilities of possible outcomes.In this context, “expected” means average if the p

5、rocess is repeated many times.The “expected” return does not even have to be a possible return.Expected ReturnsCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Expected returns are based on Suppose yo

6、u have predicted the following returns for stocks C and T in three possible states of the economy. What are the expected returns?StateProbability C T_Boom5Normal0Recession ?0.020.01RC = .3(15) + .5(10) + .2(2) = 9.9%RT = .3(25) + .5(20) + .2(1) = 17.7%Example: Expected ReturnsCop

7、yright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Suppose you have predicted theVariance and standard deviation measure the volatility of returns.Using unequal probabilities for the entire range of possib

8、ilitiesWeighted average of squared deviationsVariance and Standard DeviationCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Variance and standard deviatioConsider the previous example. What are the v

9、ariance and standard deviation for each stock?Stock C2 = .3(0.15-0.099)2 + .5(0.10-0.099)2 + .2(0.02-0.099)2 = 0.002029 = 4.50%Stock T2 = .3(0.25-0.177)2 + .5(0.20-0.177)2 + .2(0.01-0.177)2 = 0.007441 = 8.63%Example: Variance and Standard DeviationCopyright 2019 McGraw-Hill Education.All rights rese

10、rved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Consider the previous example.Consider the following information:StateProbability ABC, Inc. ReturnBoom.25 0.15Normal.50 0.08Slowdown.15 0.04Recession.10-0.03What is the expected return?What is the varian

11、ce?What is the standard deviation?Another ExampleCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Consider the following informaA portfolio is a collection of assets.An assets risk and return are impo

12、rtant in how they affect the risk and return of the portfolio.The risk-return trade-off for a portfolio is measured by the portfolio expected return and standard deviation, just as with individual assets.PortfoliosCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribut

13、ion without the prior written consent of McGraw-Hill Education.A portfolio is a collection ofSuppose you have $15,000 to invest and you have purchased securities in the following amounts. What are your portfolio weights in each security?$2000 of C$3000 of KO$4000 of INTC$6000 of BPExample: Portfolio

14、 WeightsC: 2/15 = .133KO: 3/15 = .2INTC: 4/15 = .267BP: 6/15 = .4Copyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Suppose you have $15,000 to inThe expected return of a portfolio is the weighted avera

15、ge of the expected returns of the respective assets in the portfolio.You can also find the expected return by finding the portfolio return in each possible state and computing the expected value as we did with individual securities.Portfolio Expected ReturnsCopyright 2019 McGraw-Hill Education.All r

16、ights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.The expected return of a portfConsider the portfolio weights computed previously. If the individual stocks have the following expected returns, what is the expected return for the portfolio?C:

17、19.69%KO: 5.25%INTC: 16.65%BP: 18.24%E(RP) = .133(19.69%) + .2(5.25%) + .267(16.65%) + .4(18.24%) = 15.41%Example: Expected Portfolio ReturnsCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Consider t

18、he portfolio weightsCompute the portfolio return for each state:RP = w1R1 + w2R2 + + wmRmCompute the expected portfolio return using the same formula as for an individual asset.Compute the portfolio variance and standard deviation using the same formulas as for an individual asset.Portfolio Variance

19、Copyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Compute the portfolio return fConsider the following information on returns and probabilities:Invest 50% of your money in Asset A.StateProbabilityABPor

20、tfolioBoom .430%-5%12.5%Bust .6 -10%25%7.5%What are the expected return and standard deviation for each asset?What are the expected return and standard deviation for the portfolio?Example: Portfolio VarianceCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution wit

21、hout the prior written consent of McGraw-Hill Education.Consider the following informaConsider the following information on returns and probabilities:StateProbabilityXZ Boom.2515%10%Normal.6010%9%Recession.155%10%What are the expected return and standard deviation for a portfolio with an investment

22、of $6,000 in asset X and $4,000 in asset Z?Another Example: Portfolio VarianceCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Consider the following informaRealized returns are generally not equal to

23、 expected returns.There is the expected component and the unexpected component.At any point in time, the unexpected return can be either positive or negative.Over time, the average of the unexpected component is zero.Expected vs. Unexpected ReturnsCopyright 2019 McGraw-Hill Education.All rights rese

24、rved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Realized returns are generallyAnnouncements and news contain both an expected component and a surprise component.It is the surprise component that affects a stocks price and therefore its return.This is

25、very obvious when we watch how stock prices move when an unexpected announcement is made or earnings are different than anticipated.Announcements and NewsCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Educati

26、on.Announcements and news containEfficient markets are a result of investors trading on the unexpected portion of announcements.The easier it is to trade on surprises, the more efficient markets should be.Efficient markets involve random price changes because we cannot predict surprises.Efficient Ma

27、rketsCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Efficient markets are a resultRisk factors that affect a large number of assetsAlso known as non-diversifiable risk or market riskIncludes such th

28、ings as changes in GDP, inflation, interest rates, etc.Systematic RiskCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Risk factors that affect a larRisk factors that affect a limited number of assets

29、Also known as unique risk and asset-specific riskIncludes such things as labor strikes, part shortages, etc.Unsystematic RiskCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Risk factors that affect a

30、 limTotal Return = expected return + unexpected returnUnexpected return =systematic portion + unsystematic portionTherefore, total return can be expressed as follows: Total Return = expected return+ systematic portion + unsystematic portionReturnsCopyright 2019 McGraw-Hill Education.All rights reser

31、ved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Total Return = expected returnPortfolio diversification is the investment in several different asset classes or sectors.Diversification is not just holding a lot of assets.For example, if you own 50 Inter

32、net stocks, you are not diversified.However, if you own 50 stocks that span 20 different industries, then you are diversified.DiversificationCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Portfolio

33、diversification is tTable 13.7Copyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Table 13.7Copyright 2019 McGDiversification can substantially reduce the variability of returns without an equivalent red

34、uction in expected returns.This reduction in risk arises because worse than expected returns from one asset are offset by better than expected returns from another.However, there is a minimum level of risk that cannot be diversified away and that is the systematic portion.The Principle of Diversific

35、ationCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Diversification can substantiaFigure 13.1Copyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the pri

36、or written consent of McGraw-Hill Education.Figure 13.1Copyright 2019 McThe risk that can be eliminated by combining assets into a portfolio.Often considered the same as unsystematic, unique or asset-specific riskIf we hold only one asset, or assets in the same industry, then we are exposing ourselv

37、es to risk that we could diversify away.Diversifiable RiskCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.The risk that can be eliminateTotal risk = systematic risk + unsystematic riskThe standard de

38、viation of returns is a measure of total risk.For well-diversified portfolios, unsystematic risk is very small.Consequently, the total risk for a diversified portfolio is essentially equivalent to the systematic risk.Total RiskCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction

39、 or distribution without the prior written consent of McGraw-Hill Education.Total risk = systematic risk +There is a reward for bearing risk.There is not a reward for bearing risk unnecessarily.The expected return on a risky asset depends only on that assets systematic risk since unsystematic risk c

40、an be diversified away.Systematic Risk PrincipleCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.There is a reward for bearing How do we measure systematic risk?We use the beta coefficient.What does b

41、eta tell us?A beta of 1 implies the asset has the same systematic risk as the overall market.A beta 1 implies the asset has more systematic risk than the overall market.Measuring Systematic RiskCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prio

42、r written consent of McGraw-Hill Education.How do we measure systematic rTable 13.8 Selected BetasCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Table 13.8 Selected BetasCopConsider the following in

43、formation: Standard DeviationBetaSecurity C20%1.25Security K30%0.95Which security has more total risk?Which security has more systematic risk?Which security should have the higher expected return?Total vs. Systematic RiskCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or di

44、stribution without the prior written consent of McGraw-Hill Education.Consider the following informaMany sites provide betas for companies.Yahoo! Finance provides beta, plus a lot of other information under its Key Statistics section.Enter a ticker symbol and get a basic quote.Click on Key Statistic

45、s.Work the Web ExampleCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Many sites provide betas for cConsider the previous example with the following four securities.SecurityWeightBetaC.1331.685KO.20.

46、195INTC.2671.161BP.41.434What is the portfolio beta?.133(1.685) + .2(.195) + .267(1.161) + .4(1.434) = 1.147Example: Portfolio BetasCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Consider the previo

47、us example Remember that the risk premium = expected return risk-free rate.The higher the beta, the greater the risk premium should be.Can we define the relationship between the risk premium and beta so that we can estimate the expected return?YES!Beta and the Risk PremiumCopyright 2019 McGraw-Hill

48、Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Remember that the risk premiumExample: Portfolio Expected Returns and BetasRfE(RA)ACopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution witho

49、ut the prior written consent of McGraw-Hill Education.Example: Portfolio Expected ReThe reward-to-risk ratio is the slope of the line illustrated in the previous example.Slope = (E(RA) Rf) / (A 0)Reward-to-risk ratio for previous example = (20 8) / (1.6 0) = 7.5What if an asset has a reward-to-risk

50、ratio of 8 (implying that the asset plots above the line)?What if an asset has a reward-to-risk ratio of 7 (implying that the asset plots below the line)?Reward-to-Risk Ratio: Definition and ExampleCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the

51、prior written consent of McGraw-Hill Education.The reward-to-risk ratio is thIn equilibrium, all assets and portfolios must have the same reward-to-risk ratio, and they all must equal the reward-to-risk ratio for the market.Market EquilibriumCopyright 2019 McGraw-Hill Education.All rights reserved.

52、No reproduction or distribution without the prior written consent of McGraw-Hill Education.In equilibrium, all assets andThe security market line (SML) is the representation of market equilibrium.The slope of the SML is the reward-to-risk ratio: (E(RM) Rf) / MBut since the beta for the market is alw

53、ays equal to one, the slope can be rewritten.Slope = E(RM) Rf = market risk premiumSecurity Market LineCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.The security market line (SML)The capital asset

54、pricing model defines the relationship between risk and return.E(RA) = Rf + A(E(RM) Rf)If we know an assets systematic risk, we can use the CAPM to determine its expected return.This is true whether we are talking about financial assets or physical assets.The Capital Asset Pricing Model (CAPM)Copyri

55、ght 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.The capital asset pricing modePure time value of money: measured by the risk-free rateReward for bearing systematic risk: measured by the market risk premium

56、Amount of systematic risk: measured by betaFactors Affecting Expected ReturnCopyright 2019 McGraw-Hill Education.All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education.Pure time value of money: measConsider the betas for each of the assets given earlier. If the risk-free rate is 3.15% and the market risk premium is 7.5%, what is the e