
Ultimate access to all questions.
Two portfolios have the following characteristics:
| Portfolio | Return | Beta |
|---|---|---|
| A | 8% | 0.7 |
| B | 7% | 1.1 |
Given a market return of 10% and a risk-free rate of 4%, calculate Jensen's Alpha for both portfolios and comment on which portfolio has performed better.
Explanation:
Jensen's Alpha measures the excess return of a portfolio compared to its expected return based on the Capital Asset Pricing Model (CAPM). The formula is:
Jensen's Alpha = Rp - [Rf + βp(Rm - Rf)]
Where:
For Portfolio A:
Jensen's Alpha = 0.08 - [0.04 + 0.7(0.10 - 0.04)] = 0.08 - [0.04 + 0.7(0.06)] = 0.08 - [0.04 + 0.042] = 0.08 - 0.082 = -0.002 = -0.2%
For Portfolio B:
Jensen's Alpha = 0.07 - [0.04 + 1.1(0.10 - 0.04)] = 0.07 - [0.04 + 1.1(0.06)] = 0.07 - [0.04 + 0.066] = 0.07 - 0.106 = -0.036 = -3.6%
Key Insight: Even though both portfolios underperformed expectations, Portfolio A's underperformance is much smaller than Portfolio B's, making it the relatively better performer.