The Capital Asset Pricing Model

Fama and French’s three factor model attempts to explain the variation of stock prices through a multifactor model that includes a size factor and BE/ME factor in addition to the beta risk factor. Fama-French model essentially extended the CAPM (which breaks up cause of variation of stock price into systematic risk which is non-diversifiable and idiosyncratic risk which is diversifiable) by introducing these two additional factors. Fama and French find that stocks with high beta didn’t have consistently higher returns than stocks with low beta and this indicates that beta was not a useful measure under their model. Their model is based on research findings that sensitivity of movements of the size and BE/ME factor constituted risk, and

1. True or False: According to the CAPM, a stock's expected return is positively related to its beta.

CAPM is a model that describes the relationship between risk and expected return, and the formula itself measures the expected return of the portfolio. Mathematically, when beta is higher, meaning the portfolio has more systematic risk (in comparison to the market portfolio), the formula yields a higher expected return for the portfolio (since it is multiplied by the risk premium and is added to the risk free interest rate). This makes sense because the portfolio needs to

The CAPM is a single factor model because it based on the hypothesis that required rate of return can be predicted using one factor that being systematic risk. It looks at risk and rates of returns, compares then to the stock market providing a usable measure of risk to help investors determine what return they will get for risking their money in an investment. There are a lot of assumptions and drawbacks of CAPM that lead to the conclusion that those investors utilizing this

This essay will highlight the use of Capital asset pricing model ( CAPM ) to be considered as a pricing theory model for assets . CAPM model helps investors to analyse the risk and what expectation to keep from an investment (Banz , 1981) . There are two types of risk

CAPM on the other hand is based on microeconomic ideas such as concave utilities and costless diversification. Macroeconomic events mentioned include interest rates or the cost of labor, causes the systematic risk that affects the returns of all stocks. On the other hand the firm-specific events are the unexpected microeconomic events that affect the returns of specific firms for example the death of key people that would affects the firm, but would have a insignificant effect on the

In order to test the validity of the CAPM, we have applied the two-step testing procedure for asset pricing model as proposed by Fama and Macbeth (1973) in their seminal paper.

However, the R Square of this regression is 0.5939 that means only about 59% variable can be explained by this regression. This result show that the CAPM model lacks some factors or information to explain these variable.

Even though there are flaws in the CAPM for empirical study, the approach of the linearity of expected return and risk is readily relevant. As Fama & French (2004:20) stated “… Markowitz’s portfolio model … is nevertheless a theoretical tour de force.” It could be seen that the study of this paper may possibly justify Fama & French’s study that stated the CAPM is insufficient in interpreting the expected return with respect to risk. This is due to the failure of considering the other market factors that would affect the stock price.

In this trend, there are several models to support this view of these investors, including the Modern Portfolio Theory (MPT), Capital Asset Pricing Model (CAPM) and Arbitrage Pricing Theory (APT) (Fama and French, 2004; Perold, 2004). They have been the main instruments that the rational expectation based theories have been deploying. However, this traditional paradigm has been analyzed by a number of researches that the information should not be considered to have a very important role in affecting investors (Miles and McCue, 1984), Titman and Warga (1986), Lusht (1988) and Liu and Mei (1992).

Ever since Ross (1976) proposed the Arbitrage Pricing Theory (APT) as an alternative to the capital pricing model, many economists and investors have applied APT across different markets. Whereas the traditional capital pricing model explained asset returns with one beta, sensitivity to the market return, APT decomposes the return with a multiple number of factors. This idea became particularly popular for investors who aim to gain systematic risk other than market risk. However, the model specification aspect has been challenging to many practitioners as the theory does not require any specific sets of variables to be used (Azeez 2006).

The Capital Asset Pricing Model (CAPM), was first developed by William Sharpe (1964), and later extended and clarified by John Lintner (1965) and Fischer Black (1972). Four decades after the birth of this model, CAPM is still accepted as an appropriate technique for evaluating financial assets and retains an important place in both academic scholars and finance practitioners. It is used to estimate cost of capital for firms, evaluating the performance of managed portfolios and also to determine asset prices. Since the inception of this model there have been numerous researches and empirical testing to assess the strength and the validity of the model.

This essay will illustrate the practicability of the capital asset pricing model (the CAPM). Before 30 years ago, the capital asset pricing model was a significant development. This theoretical model has been used in many large companies. Yet, many economists argue that this model has its own drawbacks. In 1992, Fama and French said that the application of CAPM could be useless which against empirical tests of the CAPM. For instance, the CAPM was seen as an obsolete theory because of the limitation of its assumptions. Main assumptions can be categorized into six aspects. First, the CAPM assumption was built on that the capital market is always in equilibrium. This assumption is difficult to achieve in the real world. Second, there are a numeral of investors who hold the same period of their asset in the market and no considering of the outcome after the investment plan. However, there are too many investors in the market, it is impossible that their time of holding the asset could be exactly the same. Therefore, the second assumption is also unachievable. The third hypothesis is that investors have unrestricted of borrowing and lending at fixed risk-free rate which is also very difficult. The fourth of assumption is assumed that there are no transaction costs and taxes. But in fact, these factors are all existed in the real market. Then, the fifth and sixth assumption shows all investors have the same expectation on their investment portfolio. Obviously, these two

Richard Roll, and University and Auburn, University of Washington, and University of Chicago educated economist, began his career researching the effect of major events of stock prices. This experience likely helped him reach the two conclusions he makes in his 1977 “A Critique Of The Asset Pricing Theory’s Tests”, one of the earliest and most influential arguments against CAPM. In the paper, Roll makes two major claims: that CAPM is actually a redundant equation that just further proves the concept of mean-variance efficiency, and that it is impossible to conclusively prove CAPM. His first claim relates to mean-variance efficiency: the idea that mathematically one must be able to create a portfolio that offers the most return for a given amount of risk. Roll claims that all CAPM is doing is testing a portfolio’s mean variance efficiency, and not actually modeling out projected future returns. The second claim in the paper is that there is not enough data about market returns for CAPM to ever prove conclusive. Even if modern technologies could help alleviate some of the burden of testing market returns for publicly traded equities, there is still no way to account for the returns of less liquid markets, where there is less public information. This means it is impossible for

The main purpose of this study is to investigate the ability of two alternative models in finance, Capital Asset Pricing Model (CAPM) and Arbitrage Pricing Theory (APT), to explain the excess return of a portfolio of stocks in Saudi Stock Exchange (TADAWUL). The regression analyses were conducted on the portfolio, which consists of 54 listed and actively traded stocks in TADAWUL. Comprising the ex-ante sample from the period of January 2000 and December 2005 and the ex-post sample from the period of January 2006 and December 2008, this study shows that none of the conditions of the validity of the CAPM was satisfied as