Performance and Evidence · Hedge Funds

A positive return can come from market exposure, systematic risk taking or manager decisions. Alpha is an estimate relative to a model, not a label for every profitable trade.

Define the comparison first

Beta describes sensitivity to a chosen market or factor. Alpha is the part of performance not explained by the specified model under its assumptions. A different benchmark or factor set can change the estimated alpha. Fees and uncertainty must also be considered.

Common systematic exposures include equity direction, credit risk, value, momentum, carry and volatility related risks. A manager may intentionally harvest such exposures. The question is whether the implementation, cost and risk fit the investor’s objective, rather than whether every return is unique skill.

Use a simplified attribution

Suppose a fund earns 9%, the cash benchmark earns 3%, and the equity market earns 11%. With an assumed equity beta of 0.5, a simple one factor model implies 3% plus 0.5 times the market’s 8% excess return, or 7%. The residual is 2 percentage points.

That 2 point residual is not proof of skill. It might reflect omitted factors, estimation error, unusual luck or valuation timing. If the reported 9% is gross while the comparison assumes net, fees further change the investor’s result. A single period is especially weak evidence.

Ask what could be replicated more simply

Compare the proposed fund with a plausible combination of inexpensive market exposures, while recognizing that a statistical resemblance is not an exact replication. Review results during different regimes and examine whether exposure changes were intentional and documented.

Some strategies earn premiums for bearing losses in difficult conditions. A smooth history can conceal exposure to rare adverse events. Evaluate the distribution of outcomes, not just the average residual. A useful attribution connects positions and decisions to results rather than relying entirely on a fitted regression.

Try it yourself

With cash at 2%, market return at 8% and beta 0.75, what return does the simple model imply? What residual remains if the fund earns 7%?

Show the worked answer

The model implies 2% plus 0.75 times 6%, or 6.5%. The residual is 0.5 percentage points before considering model uncertainty and consistent fee treatment.

Further reading

Educational material, not a recommendation to buy or sell a fund. Numerical examples are hypothetical. Fund terms, investor eligibility and tax treatment vary by product, account and jurisdiction.

Continue learning