Fat tails. For hedge fund investors, the last free item on the lunch menu
Mar 16th, 2010 | Filed under: Performance, Analytics & Metrics, Today's Post
It’s become practically cliché to note that the 2008 market crash was a stark reminder that hedge funds too can suffer at the hands of a series of highly improbably and unanticipated events – even after looking at their strategy, their diversification and the mean and variance of their past returns.
Yet a recent research study (free registration required) by TrimTabs and BarclayHedge entitled “Do Hedge Fund Investors Care About ‘Fat-Tails’ Risk” caught our attention for a theory put to test: Can hedge fund investors hedge themselves from unforeseen risk events – kurtosis, in economic-speak – that the hedge funds they’re writing checks to might be taking?
We pride ourselves on being somewhat schooled in the nuances of economic and financial market phraseology, thanks in large part to the resources of CAIA and others at our disposal (shameless plug, but CAIA has this study on building a hedge fund portfolio with kurtosis and skewness available on its Web site). But we’re also grateful when someone else defines an academic term for us, which the TrimTabs study thankfully does:
“Kurtosis measures the risk of a highly implausible event coming to pass more frequently than one would expect from a normally distributed variable.”
TrimTabs and BarclayHedge analyze how the kurtosis of hedge fund returns is measured; how, if at all, it impacts hedge fund flows; and if kurtosis is in fact priced in to hedge fund returns, or if non-normal returns offer arbitrage opportunities for sophisticated investors.
The study finds that in contrast to returns on individual securities and contracts like stocks, gold, oil or bonds, individual hedge fund returns display significant excess kurtosis, for the most part thanks to hedge funds’ ability to utilize leverage. (See illustration below.)
Indeed, the study’s results show that hedge fund returns display high levels of kurtosis. At the fund level, kurtosis averaged 33.1 in the past 10 years. Kurtosis is also extremely volatile, with peaks of 127.8 in 2003 (a stock market bottom) and 91.8 in 2007 (likely due to the sharp and simultaneous sell-off of quantitative strategies in the summer).
In fact, the results of the study show even higher levels of kurtosis than most academic studies because it focuses on individual fund returns rather than a composite hedge fund index.
So is that a good thing or a bad thing? At first blush, its not a good thing. All else equal, investors should avoid high kurtosis. A 90% loss means near ruin for investors, and a 90% gain does not offset it, the report notes. The fact that hedge fund returns display much more kurtosis than the assets in which they invest suggests that kurtosis is the result of leverage, which magnifies the likelihood of extreme outcomes, as the chart below shows.
The level of kurtosis also highly depends on the hedge fund strategy being employed. According to the study, fixed income and convertible arbitrage strategies show the most kurtosis, while equity market neutral is the only strategy for which the presence of kurtosis is not certain.
“This too, we ascribe to leverage,” the study notes. “It is not uncommon for fixed income and convertible arbitrage funds to use leverage ratios of 20:1, but strategy constraints and the volatility of stocks force much more caution from equity market neutral funds.”
On deeper reflection, however, the study notes that since most hedge fund investors do not seem to care about “fat-tails” risk, sophisticated investors with the ability to diversify their hedge fund portfolios should be able to diversify away kurtosis without any cost in terms of returns or variance – good news.
Conclusion: Kurtosis within hedge funds remains one of the last free lunches for sophisticated investors. Translation: If the buffet has enough different kinds of food to sample, and you know the right way to mix them, your chances of getting an unforeseen wallop of indigestion will be less.
Related Posts
- A Strategy Aiming to Pump Returns Gains Clout but May Be “No Free Lunch”
- How much would you pay for a free (McAlpha Meal) lunch?
- Researchers to hedge fund investors: Don’t throw away Sharpe ratios just yet
- When skittish hedge fund investors and lenders become a problem for everyone
- Despite operational risk reporting standards, chasm remains between hedge fund investors and managers




















