Brad Barber is one smart, hard-working professor. Among other things, with his U.C.-Davis colleague Terrance Odean, he analyzed the trading records over several recent years of a discount broker with tens of thousands of customers. The results – that most of us trade too much, that women do better than men – are instructive. Click here for his Web site.
Some of it is awfully academic (remind me what the “geometric mean” is), but the message is clear: The more you trade, the more spreads and commissions you rack up. (Not to mention taxes! Those weren’t even included.) And on average, this proves to be a real drag on your performance. Men, being overconfident and more risk-prone, trade more than women. Single men do even worse.
Professor Barber looked, too, at the performance of 166 investment clubs. His finding? “The average club tilts its common stock investment toward high-beta, small, growth stocks, and turns over 65 percent of its portfolio annually. The average club lagged the performance of a broad-based market index by over three percent per year.” Sixty percent of the clubs underperformed the index.
Do your homework. Buy and hold. Get married.