PT  - JOURNAL ARTICLE
AU  - Jon A. Christopherson
AU  - Wayne E. Ferson
AU  - Andrew L. Turner
TI  - Performance Evaluation Using Conditional Alphas and Betas
AID  - 10.3905/jpm.1999.319774
DP  - 1999 Oct 31
TA  - The Journal of Portfolio Management
PG  - 59--72
VI  - 26
IP  - 1
4099  - https://pm-research.com/content/26/1/59.short
4100  - https://pm-research.com/content/26/1/59.full
AB  - Unconditional measures can incorrectly measure alpha and beta when portfolio managers engage in dynamic trading strategies or change their alphas and betas in response to publicly available information about the economy. The authors advocate continual performance evaluation (CPE) to measure dynamic alphas and betas. Comparing a sample of 261 manager portfolios over 1980–1996 to the Russell 3000, they find that a portfolio of the top quintile of CAPM alphas outperforms the bottom quintile by 1.45% annualized, while the spread for quintiles of CPE alphas is 4.00%. When style indexes are used to compute alphas, the spread between top and bottom quintiles of CAPM alphas becomes a erverse-2.41% annualized. On the other hand, the top quintile also outperforms the average manager by 1.70% and the Russell 3000 by 2.42% annualized. While higher CPE alphas do not guarantee superior returns, they are more likely to successfully forecast returns than CAPM alphas.