Explanation

Alpha (α) in finance refers to the excess return of an investment relative to the return of a benchmark index. It represents the value that a portfolio manager adds or subtracts from a fund's return relative to a benchmark.

Key points about alpha:

1. Definition: Alpha measures the difference between a portfolio's actual returns and its expected performance, given its level of risk (beta).

2. Formula: α = Actual Return - Expected Return (based on CAPM) Expected Return = Risk-Free Rate + β × (Market Return - Risk-Free Rate)

3. Interpretation:

   • Positive alpha: The portfolio outperformed its benchmark after adjusting for risk
   • Negative alpha: The portfolio underperformed its benchmark after adjusting for risk
   • Zero alpha: The portfolio performed exactly as expected given its risk level

4. Why Option C is correct: Alpha specifically measures the difference between the return of an actively managed portfolio and what would have been earned by a passive portfolio (benchmark) with the same level of risk.

Why other options are incorrect:

• Option A: Market sentiment is typically measured by indicators like the VIX (Volatility Index), put/call ratios, or investor surveys, not alpha.
• Option B: This describes beta (β), not alpha. Beta measures systematic risk relative to the market.

Practical Application: Alpha is a key metric in evaluating portfolio manager performance. A positive alpha indicates skill in security selection or market timing, while a negative alpha suggests the manager failed to add value beyond what could be achieved through passive investing.