Why Winners Quit

In the second half of Chapter 22, Larry Harris digs into why that 5-star mutual fund you saw in a magazine might be a terrible investment. The industry is designed to hide the losers and highlight the lucky.

Survivorship Bias: The Graveyard of Funds

The biggest problem in performance data is Survivorship Bias.

• The Move: A fund company starts 50 different “active” funds. Five of them do really well by pure luck, and 45 of them do terribly.
• The Trick: They shut down the 45 losers and merge them into the winners.
• The Result: When you look at their brochure, they show you a “family of funds” where every single one has beaten the market for 5 years. You don’t see the graveyard of failed funds that paid for those winners.

The “Peso Problem”

Some trading strategies look like absolute genius until they suddenly explode.

• Selling Volatility: Imagine a strategy that makes 1% every month, like clockwork. The manager looks like a god.
• The Catch: The strategy involves a hidden risk that has a 1-in-100 chance of losing 90% of the fund’s value.
• The Trap: Until that “Black Swan” event happens, the fund looks skilled. But the manager isn’t skilled; they are just harvesting a risk premium and waiting for the bomb to go off.

Regression to the Mean

If a manager is at the top of the charts this year, where will they be next year? Statistically, the answer is: closer to the average. Luck doesn’t last. This is why the “hot” funds of 2020 were often the biggest losers of 2022. The lucky streak ended, and they regressed to the mean.

How to Spot a Real Edge (Comparative Advantage)

So, how do you actually find a good manager? Harris says you should ignore the returns and look for a Comparative Advantage. Ask: Why do you think you are better than everyone else?

• Better Data: Do they have a proprietary satellite feed that tracks retail traffic?
• Better Tech: Do they have a faster connection to the exchange?
• Better Discipline: Are they more patient than the rest of the market?

If a manager can’t explain their edge, they probably don’t have one.

The Case of Warren Buffet

Is Warren Buffet just the luckiest guy in history? Harris did the math. Given the size of the “investor pool” in 1965 and Buffet’s 36-year track record, the probability of him being purely lucky is about 0.5%. Conclusion: Buffet is actually skilled. But for every Warren Buffet, there are 10,000 “Mini-Buffets” who are just on a lucky streak.

Summary: The Index Fund Argument

Because it is so hard to find skill and so easy to be fooled by luck, the rational choice for almost everyone is to buy index funds. You won’t be the top performer, but you’re guaranteed to not be the fool who got fleeced by a “lucky” manager.

Next time, we’ll look at Chapter 23 and see how these index markets actually work.

Next Post: Index and Portfolio Markets