Mikhail Tupitsyn and Paul Lajbcygier, authors of the August 2015 paper “Passive Hedge Funds,” sought to answer the question: Do most hedge fund managers generate returns through managerial skill?
Their hypothesis was: “In order to demonstrate skill, a hedge fund manager must generate enhanced performance through active management. Such skill should be manifest through nonlinear exposure to the systematic risk factors that drive hedge fund returns and as a consequence of active management outperformance should ensue.” Note that nonlinear models have payoff structures such as those often found in options.
To explore this issue, the authors used a Credit Suisse/TASS database covering the period January 1994 to September 2010. The data included TASS hedge fund indexes for convertible arbitrage, dedicated short bias, emerging markets, equity market neutral, event-driven, fixed-income arbitrage, global macro, long/short equity, managed futures, multistrategy and fund-of-funds styles, in addition to a composite hedge fund index.
To mitigate the well-known survivorship and backfill biases in hedge fund data, the authors included funds from the TASS “graveyard” database, which stores historical data on defunct funds.
The final sample consisted of 5,580 hedge funds, of which 2,670 were active and 2,910 were defunct. The high percentage of defunct funds is itself an indicator of just how large a problem survivorship bias can be. The following is a summary of Tupitsyn and Lajbcygier’s key findings:
- A large majority of hedge fund managers rely on “passive” linear risk exposures to generate their returns. In other words, many behave like alternative beta portfolios.
- Only about 20 percent of hedge funds exhibit nonlinear exposure to systematic risk factors.
- Funds with “passive” linear exposures outperform most “active” managers that try to deploy skill. On average, active (nonlinear) funds are inferior to linear (passive) funds in terms of both raw and risk-adjusted returns (they have lower Sharpe ratios). They also have greater negative tail risk (meaning they exhibit negative skewness and excess kurtosis).
- Since most hedge fund strategies are significantly correlated with well-known risk factors, the results confirm that hedge fund strategies are not market neutral (they aren’t really hedging).
- Each of the hedge fund styles analyzed, with the exception of the managed futures category, showed a statistically significant correlation with equity market returns. Said another way, they aren’t good hedges for equity exposures.