A Comparision Between Explanatory Power of CAMP and D-CAPM in Predicting Expected Stock Return

Subject Areas : Financial Knowledge of Securities Analysis

افسانه توانگر ¹ ( مسئول مکاتبات )
مهدی Kh ² ( ندارد )

Received: 2011-02-04 Accepted : 2011-05-15 Published : 2011-03-21

Keywords: CAPM, D-CAPM, Expected Return, emerging market, Beta, d-beta,

Abstract :

Most of the academic studies identified β factor as a risk-based measure of stock return volatility and used Capital Assets Pricing Model (CAPM) to measure portfolio risk and estimate expected return. Over the last few years, the semi-variance of stock return developed proposing the downside β as an alternative measure of risk. Based on Downside CAPM (D-CAPM), we investigated the capability of the CAPM and D-CAPM to estimate required returns on equity in Tehran Stock Exchange as an emerging market and focused on comparing the ability of β factor to explain the cross-section of returns relative to that of alternative risk variable as downside β. Considering information of stock return of 138 firms from 2005 to 2009, we established a hypothesis as: “The D-CAPM has more explanatory power to predict the expected stock return volatility rather than CAPM.” Through studying the relationship between stock returns and beta and d-beta, stable and direct significant correlation of d-beta and stock returns clarify the importance of d-beta and D-CAPM in measuring the risk and expected return rather than beta and CAPM.