博迪《投资学》(第10版)笔记和课后习题详解 第11章~第13章【圣才出品】

第2章金融工具2.1 复习笔记1.货币市场工具（1）主要货币市场工具①国库券国库券是指政府部门为筹集预算资金，向投资者出具的承诺在一定时期内还本付息的债务凭证。

我国国库券的期限最短的为一年，而西方国家国库券品种较多，一般可分为3个月、6个月、9个月、1年期四种，其面额起点各国不一。

国库券采用不记名形式，无须经过背书就可以转让流通。

在国外，国库券期限均在一年以内，且大多是零息债券。

在本书中，国库券即政府通过向公众出售债券而筹集到资金，投资者则按低于面值的折价购买，在债券到期日债券持有人从政府获得等额于债券面值的支付的一种金融工具。

购买价与面值之差就是投资者的所得收益。

美国国库券是货币市场上所有金融工具中流动性最强的一种。

国库券流动性强、风险低并且收入免税，其利率是市场利率变动情况的集中反映。

②大额可转让存单大额可转让存单是指商业银行为吸收资金而发行的载有一定存款金额、期限、利率并可在市场上流通转让的短期信用工具。

大额可转让存单市场具有期限短(一般在1年以内)，面额固定且起点较高，大多不记名，不可提前支取但可流通转让，利率较高等特点。

大额存单是银行的定期存款。

定期存款的存款者不能随时任意提取存款，银行只在定期存款到期时才付给储户利息与本金。

在美国，面额超过100 000美元的大额存单通常可以转让。

短期大额可转让存单市场流动性很强，但到期日在6个月或以上的大额存单，其流动性会大大下降。

③商业票据商业票据指以商业信用进行交易时所开立的证明债权债务关系的书面凭证，其中又含商业本票与商业汇票两种。

商业本票是债务人向债权人发出的、承诺在一定时期内支付一定数额款项的债务凭证。

商业汇票是债权人向债务人发出的无条件支付命令，命令债务人在限定日期内向债权人或第三者支付一定数额的款项。

商业汇票可以背书转让，亦可申请贴现。

通常情况下商业票据由银行的信誉担保，它使借款者在需要时获得现金以便在票据到期日能够向商业票据的持有者支付。

第10章指数模型10.1 复习笔记1．单指数证券市场(1)单指数模型①单指数模型的定义式马科维茨模型在实际操作中存在两个问题，一是需要估计大量的数据；二是该模型应用中相关系数确定或者估计中的误差会导致结果无效。

单指数模型大降低了马科维茨资产组合选择程序的数据数量，它把精力放在了对证券的专门分析中。

因为不同企业对宏观经济事件有不同的敏感度。

所以，如果记宏观因素的非预测成分为F，记证券i对宏观经济事件的敏感度为βi；则证券i的宏观成分为，则股票收益的单因素模型为：②单指数模型收益率的构成因为指数模型可以把实际的或已实现的证券收益率区分成宏观(系统)的与微观(公司特有)的两部分。

每个证券的收益率是三个部分的总和：如果记市场超额收益R M的方差为σ2M，则可以把每个股票收益率的方差拆分成两部分：（2）指数模型的估计单指数模型表明，股票GM的超额收益与标准普尔500指数的超额收益之间的关系由下式给定：R i=αi+βi R M+e i该式通过βi来测度股票i对市场的敏感度，βi是回归直线的斜率。

回归直线的截距是αi，它代表了平均的公司特有收益。

在任一时期里，回归直线的特定观测偏差记为e i，称为残值。

每一个残值都是实际股票收益与由描述股票同市场之间的一般关系的回归方程所预测出的股票收益之间的差异。

这些量可以用标准回归技术来估计。

（3）指数模型与分散化资产组合的方差为其中定义资产组合方差的系统风险成分为依赖于市场运动的部分为它也依赖于单个证券的敏感度系数。

这部分风险依赖于资产组合的贝塔和σ2M，不管资产组合分散化程度如何都不会改变。

相比较，资产组合方差的非系统成分是σ2(e P)，它来源于公司特有成分e i。

因为这些e i 是独立的，都具有零期望值，所以可以得出这样的结论：随着越来越多的股票加入到资产组合中，公司特有风险倾向于被消除掉，非市场风险越来越小。

当各资产为等权重，且e i不相关时，有。

式中，为公司特有方差的均值。

投资学（博迪）第10版课后习题答...CHAPTER 10: ARBITRAGE PRICING THEORY ANDMULTIFACTOR MODELS OF RISK AND RETURN PROBLEM SETS1. The revised estimate of the expected rate of return on the stock would be the oldestimate plus the sum of the products of the unexpected change in each factor times the respective sensitivity coefficient: Revised estimate = 12% + [(1 × 2%) + (0.5 × 3%)] = 15.5%Note that the IP estimate is computed as: 1 × (5% - 3%), and the IR estimate iscomputed as: 0.5 × (8% - 5%).2. The APT factors must correlate with major sources of uncertainty, i.e., sources ofuncertainty that are of concern to many investors. Researchers should investigatefactors that correlate with uncertainty in consumption and investment opportunities.GDP, the inflation rate, and interest rates are among the factors that can be expected to determine risk premiums. In particular, industrial production (IP) is a goodindicator of changes in the business cycle. Thus, IP is a candidate for a factor that is highly correlated with uncertainties that have to do with investment andconsumption opportunities in the economy.3. Any pattern of returns can be explained if we are free to choose an indefinitelylarge number of explanatory factors. If a theory of asset pricing is to have value, itmust explain returns using a reasonably limited number of explanatory variables(i.e., systematic factors such as unemployment levels, GDP, and oil prices).4. Equation 10.11 applies here:E(r p) = r f + βP1 [E(r1 ) ?r f ] + βP2 [E(r2 ) – r f]We need to find the risk premium (RP) for each of the two factors:RP1 = [E(r1 ) ?r f] and RP2 = [E(r2 ) ?r f]In order to do so, we solve the following system of two equations with two unknowns: .31 = .06 + (1.5 ×RP1 ) + (2.0 ×RP2 ).27 = .06 + (2.2 ×RP1 ) + [(–0.2) ×RP2 ]The solution to this set of equations isRP1 = 10% and RP2 = 5%Thus, the expected return-beta relationship isE(r P) = 6% + (βP1× 10%) + (βP2× 5%)5. The expected return for portfolio F equals the risk-free rate since its beta equals 0.For portfolio A, the ratio of risk premium to beta is (12 ?6)/1.2 = 5For portfolio E, the ratio is lower at (8 – 6)/0.6 = 3.33This implies that an arbitrage opportunity exists. For instance, you can create aportfolio G with beta equal to 0.6 (the same as E’s) by combining portfolio A and portfolio F in equal weights. The expected return and beta for portfolio G are then: E(r G) = (0.5 × 12%) + (0.5 × 6%) = 9%βG = (0.5 × 1.2) + (0.5 × 0%) = 0.6Comparing portfolio G to portfolio E, G has the same betaand higher return.Therefore, an arbitrage opportunity exists by buying portfolio G and selling anequal amount of portfolio E. The profit for this arbitrage will ber G –r E =[9% + (0.6 ×F)] ?[8% + (0.6 ×F)] = 1%That is, 1% of the funds (long or short) in each portfolio.6. Substituting the portfolio returns and betas in the expected return-beta relationship,we obtain two equations with two unknowns, the risk-free rate (r f) and the factor risk premium (RP):12% = r f + (1.2 ×RP)9% = r f + (0.8 ×RP)Solving these equations, we obtainr f = 3% and RP = 7.5%7. a. Shorting an equally weighted portfolio of the ten negative-alpha stocks andinvesting the proceeds in an equally-weighted portfolio of the 10 positive-alpha stocks eliminates the market exposure and creates a zero-investmentportfolio. Denoting the systematic market factor as R M, the expected dollarreturn is (noting that the expectation of nonsystematic risk, e, is zero):$1,000,000 × [0.02 + (1.0 ×R M)] ? $1,000,000 × [(–0.02) + (1.0 ×R M)]= $1,000,000 × 0.04 = $40,000The sensitivity of the payoff of this portfolio to the market factor is zerobecause the exposures of the positive alpha and negative alpha stocks cancelout. (Notice that the terms involving R M sum to zero.) Thus, the systematiccomponent of total risk is also zero. The variance of the analyst’s profit is notzero, however, since this portfolio is not well diversified.For n = 20 stocks (i.e., long 10 stocks and short 10 stocks) the investor willhave a $100,000 position (either long or short) in each stock. Net marketexposure is zero, but firm-specific risk has not been fully diversified. Thevariance of dollar returns from the positions in the 20 stocks is20 × [(100,000 × 0.30)2] = 18,000,000,000The standard deviation of dollar returns is $134,164.b. If n = 50 stocks (25 stocks long and 25 stocks short), the investor will have a$40,000 position in each stock, and the variance of dollar returns is50 × [(40,000 × 0.30)2] = 7,200,000,000The standard deviation of dollar returns is $84,853.Similarly, if n = 100 stocks (50 stocks long and 50 stocks short), the investorwill have a $20,000 position in each stock, and the variance of dollar returns is100 × [(20,000 × 0.30)2] = 3,600,000,000The standard deviation of dollar returns is $60,000.Notice that, when the number of stocks increases by a factorof 5 (i.e., from 20 to 100), standard deviation decreases by a factor of 5= 2.23607 (from$134,164 to $60,000).8. a. )(σσβσ2222e M +=88125)208.0(σ2222=+×=A50010)200.1(σ2222=+×=B97620)202.1(σ2222=+×=Cb. If there are an infinite number of assets with identical characteristics, then awell-diversified portfolio of each type will have only systematic risk since thenonsystematic risk will approach zero with large n. Each variance is simply β2 × market variance:222Well-diversified σ256Well-diversified σ400Well-diversified σ576A B C;;;The mean will equal that of the individual (identical) stocks.c. There is no arbitrage opportunity because the well-diversified portfolios allplot on the security market line (SML). Because they are fairly priced, there isno arbitrage.9. a. A long position in a portfolio (P) composed of portfoliosA andB will offer anexpected return-beta trade-off lying on a straight linebetween points A and B.Therefore, we can choose weights such that βP = βC but with expected returnhigher than that of portfolio C. Hence, combining P with a short position in Cwill create an arbitrage portfolio with zero investment, zero beta, and positiverate of return.b. The argument in part (a) leads to the proposition that the coefficient of β2must be zero in order to preclude arbitrage opportunities.10. a. E(r) = 6% + (1.2 × 6%) + (0.5 × 8%) + (0.3 × 3%) = 18.1%b.Surprises in the macroeconomic factors will result in surprises in the return ofthe stock:Unexpected return from macro factors =[1.2 × (4% –5%)] + [0.5 × (6% –3%)] + [0.3 × (0% – 2%)] = –0.3%E(r) =18.1% ? 0.3% = 17.8%11. The APT required (i.e., equilibrium) rate of return on the stock based on r f and thefactor betas isRequired E(r) = 6% + (1 × 6%) + (0.5 × 2%) + (0.75 × 4%) = 16% According to the equation for the return on the stock, the actually expected return on the stock is 15% (because the expected surprises on all factors are zero bydefinition). Because the actually expected return based on risk is less than theequilibrium return, we conclude that the stock is overpriced.12. The first two factors seem promising with respect to thelikely impact on the firm’scost of capital. Both are macro factors that would elicit hedging demands acrossbroad sectors of investors. The third factor, while important to Pork Products, is a poor choice for a multifactor SML because the price of hogs is of minor importance to most investors and is therefore highly unlikely to be a priced risk factor. Better choices would focus on variables that investors in aggregate might find moreimportant to their welfare. Examples include: inflation uncertainty, short-terminterest-rate risk, energy price risk, or exchange rate risk. The important point here is that, in specifying a multifactor SML, we not confuse risk factors that are important toa particular investor with factors that are important to investors in general; only the latter are likely to command a risk premium in the capital markets.13. The formula is ()0.04 1.250.08 1.50.02.1717%E r =+×+×==14. If 4%f r = and based on the sensitivities to real GDP (0.75) and inflation (1.25),McCracken would calculate the expected return for the Orb Large Cap Fund to be:()0.040.750.08 1.250.02.040.0858.5% above the risk free rate E r =+×+×=+=Therefore, Kwon’s fundamental analysis estimate is congruent with McCr acken’sAPT estimate. If we assume that both Kwon and McCracken’s estimates on the return of Orb’s Large Cap Fund are accurate, then no arbitrage profit is possible.15. In order to eliminate inflation, the following three equations must be solvedsimultaneously, where the GDP sensitivity will equal 1 in the first equation,inflation sensitivity will equal 0 in the second equation and the sum of the weights must equal 1 in the third equation.1.1.250.75 1.012.1.5 1.25 2.003.1wx wy wz wz wy wz wx wy wz ++=++=++=Here, x represents Orb’s High Growth Fund, y represents Large Cap Fund and z represents Utility Fund. Using algebraic manipulation will yield wx = wy = 1.6 and wz = -2.2.16. Since retirees living off a steady income would be hurt by inflation, this portfoliowould not be appropriate for them. Retirees would want a portfolio with a return positively correlated with inflation to preserve value, and less correlated with the variable growth of GDP. Thus, Stiles is wrong. McCracken is correct in that supply side macroeconomic policies are generally designed to increase output at aminimum of inflationary pressure. Increased output would mean higher GDP, which in turn would increase returns of a fund positively correlated with GDP.17. The maximum residual variance is tied to the number of securities (n ) in theportfolio because, as we increase the number of securities, we are more likely to encounter securities with larger residual variances. The starting point is todetermine the practical limit on the portfolio residualstandard deviation, σ(e P ), that still qualifies as a well-diversified portfolio. A reasonable approach is to compareσ2(e P) to the market variance, or equivalently, to compare σ(e P) to the market standard deviation. Suppose we do n ot allow σ(e P) to exceed pσM, where p is a small decimal fraction, for example, 0.05; then, the smaller the value we choose for p, the more stringent our criterion for defining how diversified a well-diversified portfolio must be.Now construct a portfolio of n securities with weights w1, w2,…,w n, so that Σw i =1. The portfolio residual variance is σ2(e P) = Σw12σ2(e i)To meet our practical definition of sufficiently diversified, we require this residual variance to be less than (pσM)2. A sure and simple way to proceed is to assume the worst, that is, assume that the residual variance of each security is the highest possible value allowed under the assumptions of the problem: σ2(e i) = nσ2MIn that case σ2(e P) = Σw i2 nσM2Now apply the constraint: Σw i2nσM2 ≤ (pσM)2This requires that: nΣw i2 ≤ p2Or, equivalently, that: Σw i2 ≤ p2/nA relatively easy way to generate a set of well-diversified portfolios is to use portfolio weights that follow a geometric progression, since the computations then become relatively straightforward. Choose w1 and a common factor q for the geometric progression such that q < 1. Therefore, the weight on each stock is a fraction q of the weight on the previous stock in the series. Then the sum of n terms is:Σw i= w1(1– q n)/(1– q) = 1or: w1 = (1– q)/(1– q n)The sum of the n squared weights is similarly obtained from w12 and a common geometric progression factor of q2. ThereforeΣw i2 = w12(1– q2n)/(1– q 2)Substituting for w1 from above, we obtainΣw i2 = [(1– q)2/(1– q n)2] × [(1– q2n)/(1– q 2)]For sufficient diversification, we choose q so that Σw i2 ≤ p2/nFor example, continue to assume that p = 0.05 and n = 1,000. If we chooseq = 0.9973, then we will satisfy the required condition. At this value for q w1 = 0.0029 and w n = 0.0029 × 0.99731,000 In this case, w1 is about 15 times w n. Despite this significant departure from equal weighting, this portfolio is nevertheless well diversified. Any value of q between0.9973 and 1.0 results in a well-diversified portfolio. As q gets closer to 1, theportfolio approaches equal weighting.18. a. Assume a single-factor economy, with a factor risk premium E M and a (large)set of well-diversified portfolios with beta βP. Suppose we create a portfolio Zby allocating the portion w to portfolio P and (1 – w) to the market portfolioM. The rate of return on portfolio Z is:R Z = (w × R P) + [(1 –w) × R M]Portfolio Z is riskless if we choose w so that βZ = 0. This requires that:βZ = (w × βP) + [(1 –w) × 1] = 0 ?w = 1/(1 –βP) and (1 – w) = –βP/(1 –βP)Substitute this value for w in the expression for R Z:R Z = {[1/(1 –βP)] × R P} –{[βP/(1 –βP)] × R M}Since βZ = 0, then, in order to avoid arbitrage, R Z must be zero.This implies that: R P = βP × R MTaking expectations we have:E P = βP × E MThis is the SML for well-diversified portfolios.b. The same argument can be used to show that, in a three-factor model withfactor risk premiums E M, E1 and E2, in order to avoid arbitrage, we must have:E P = (βPM × E M) + (βP1 × E1) + (βP2 × E2)This is the SML for a three-factor economy.19. a. The Fama-French (FF) three-factor model holds that one of the factors drivingreturns is firm size. An index with returns highly correlated with firm size (i.e.,firm capitalization) that captures this factor is SMB (small minus big), thereturn for a portfolio of small stocks in excess of the return for a portfolio oflarge stocks. The returns for a small firm will be positively correlated withSMB. Moreover, the smaller the firm, the greater its residual from the othertwo factors, the market portfolio and the HML portfolio, which is the returnfor a portfolio of high book-to-market stocks in excess of the return for aportfolio of low book-to-market stocks. Hence, the ratio of the variance of thisresidual to the variance of the return on SMB will be larger and, together withthe higher correlation, results in a high beta on the SMB factor.b.This question appears to point to a flaw in the FF model. The model predictsthat firm size affects average returns so that, if two firms merge into a largerfirm, then the FF model predicts lower average returns for the merged firm.However, there seems to be no reason for the merged firm to underperformthe returns of the component companies, assuming that the component firmswere unrelated and that they will now be operated independently. We mighttherefore expect that the performance of the merged firm would be the sameas the performance of a portfolio of the originally independent firms, but theFF model predicts that the increased firm size will result in lower averagereturns. Therefore, the question revolves around the behavior of returns for aportfolio of small firms, compared to the return for larger firms that resultfrom merging those small firms into larger ones. Had past mergers of smallfirms into larger firms resulted, on average, in no change in the resultantlarger firms’ stock return characteristics (compared to the portfolio of stocksof the merged firms), the size factor in the FF model would have failed.Perhaps the reason the size factor seems to help explain stock returns is that,when small firms become large, the characteristics of their fortunes (andhence their stock returns) change in a significant way. Put differently, stocksof large firms that result from a merger of smaller firms appear empirically tobehave differently from portfolios of the smaller component firms.Specifically, the FF model predicts that the large firm will have a smaller riskpremium. Notice that this development is not necessarily a bad thing for thestockholders of the smaller firms that merge. The lower risk premium may bedue, in part, to the increase in value of the larger firm relative to the mergedfirms.CFA PROBLEMS1. a. This statement is incorrect. The CAPM requires a mean-variance efficientmarket portfolio, but APT does not.b.This statement is incorrect. The CAPM assumes normallydistributed securityreturns, but APT does not.c. This statement is correct.2. b. Since portfolio X has β = 1.0, then X is the market portfolio and E(R M) =16%.Using E(R M ) = 16% and r f = 8%, the expected return for portfolio Y is notconsistent.3. d.4. c.5. d.6. c. Investors will take on as large a position as possible only if the mispricingopportunity is an arbitrage. Otherwise, considerations of risk anddiversification will limit the position they attempt to take in the mispricedsecurity.7. d.8. d.。

第1章投资环境1.1 复习笔记1.金融资产与实物资产（1）概念实物资产指经济生活中所创造的用于生产商品和提供服务的资产。

实物资产包括：土地、建筑物、知识、机械设备以及劳动力。

实物资产和“人力”资产是构成整个社会的产出和消费的主要内容。

金融资产是实物资产所创造的利润或政府的收入的要求权。

金融资产主要指股票或债券等有价证券。

金融资产是投资者财富的一部分，但不是社会财富的组成部分。

（2）两种资产的区分①实物资产能够创造财富和收入，而金融资产却只是收入或财富在投资者之间的配置的一种手段。

②实物资产通常只在资产负债表的资产一侧出现，而金融资产却可以作为资产或负债在资产负债表的两侧都出现。

对企业的金融要求权是一种资产，但是，企业发行的这种金融要求权则是企业的负债。

③金融资产的产生和消除一般要通过一定的商务过程。

例如，当贷款被支付后，债权人的索偿权(一种金融资产)和债务人的债务(一种金融负债)就都消失了。

而实物资产只能通过偶然事故或逐渐磨损来消除。

2．金融市场（1）金融市场与经济①金融市场的概念金融市场是指以金融资产为交易对象而形成的供求关系及其机制的总和。

它包括三层含义，一是它是金融资产进行交易的一个有形和无形的场所；二是它反映了金融资产的供应者和需求者之间所形成的供求关系；三是它包含了金融资产交易过程中所产生的运行机制。

②金融市场的作用a.金融市场允许人们通过金融资产储蓄财富，使人们消费与收入在时间上分离。

人们可以通过调整消费期获得最满意的消费。

b.金融市场使人们可以通过金融资产的买卖来分配实物资产的风险。

c.金融市场保证了公司经营权和所有权的分离。

③代理问题代理问题是指公司的管理者追求自己的利益而非公司的利益所产生的管理者与股东潜在的利益冲突。

解决代理问题的管理机制有：期权等激励机制、通过董事会解雇管理者以及雇佣独立人士监控管理者。

绩效差的公司通常面临着被收购的危机，这是一种外部的激励。

公司治理危机包括会计丑闻、分析师丑闻和首次公开发行中的问题。