The Valuation of Security Analysis
Active portfolio management is commonly partitioned into two types of activities: market timing, which requires forecasts of broad-based market movements, and security analysis, which requires the selection of individual stocks that are perceived to be underpriced by the market. Merton (1981) has provided an inciteful and easily-implemented means to place a value on market timing skills. In contrast, while a normative theory of stock selection was outlined long ago in Treynor and Black's (1973) work, no convenient means of valuing potential selection ability has yet been devised. We present a framework in which the value of a security analyst can be computed. We also treat market timing ability in this framework, and therefore can compare the relative values of each type of investment analysts. We find that stock selection is potentially extremely valuable, but that its value depends critically on the forecast interval, on the correlation structure of residual stock returns, and on the ability to engage in short sales. Finally, we show how to modify the value of selection for the important case in which analysts' forecasts of stocks' alphas are subject to error.
|Date of creation:||Jun 1986|
|Date of revision:|
|Publication status:||published as Kane, Alex, Alan J. Marcus, and Robert R. Trippi. "The Valuation of Security Analysis." Journal of Portfolio Management 25, 3 (Spring 1999): 25-36.|
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- Dhrymes, Phoebus J & Friend, Irwin & Gultekin, N Bulent, 1984. " A Critical Reexamination of the Empirical Evidence on the Arbitrage Pricing Theory," Journal of Finance, American Finance Association, vol. 39(2), pages 323-46, June.
- Merton, Robert C., 1971.
"Optimum consumption and portfolio rules in a continuous-time model,"
Journal of Economic Theory,
Elsevier, vol. 3(4), pages 373-413, December.
- R. C. Merton, 1970. "Optimum Consumption and Portfolio Rules in a Continuous-time Model," Working papers 58, Massachusetts Institute of Technology (MIT), Department of Economics.
- Sharpe, William F., 1967. "Portfolio Analysis," Journal of Financial and Quantitative Analysis, Cambridge University Press, vol. 2(02), pages 76-84, June.
- Roll, Richard & Ross, Stephen A, 1984. " A Critical Reexamination of the Empirical Evidence on the Arbitrage Pricing Theory: A Reply," Journal of Finance, American Finance Association, vol. 39(2), pages 347-50, June.
- Admati, Anat R & Ross, Stephen A, 1985. "Measuring Investment Performance in a Rational Expectations Equilibrium Model," The Journal of Business, University of Chicago Press, vol. 58(1), pages 1-26, January.
- William F. Sharpe, 1963. "A Simplified Model for Portfolio Analysis," Management Science, INFORMS, vol. 9(2), pages 277-293, January.
- Jensen, Michael C, 1969. "Risk, The Pricing of Capital Assets, and the Evaluation of Investment Portfolios," The Journal of Business, University of Chicago Press, vol. 42(2), pages 167-247, April.
- Roll, Richard & Ross, Stephen A, 1980. " An Empirical Investigation of the Arbitrage Pricing Theory," Journal of Finance, American Finance Association, vol. 35(5), pages 1073-1103, December.
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