He talks with Cheryl Glaser on Thursday mornings. Online traders do even worse because the Internet makes it so easy and cheap to trade.
Online traders lag the indexes by an average three percentage points.
The reason people trade so much is because of overconfidence. People become irrational over their knowledge and control over markets. Investors who over-traded were under diversified, tended to hang on to their losers and bought stocks that grabbed their attention with some hot news item. Investors don't take into account the costs of commissions or taxes when they over-trade Men are more overconfident than women in trading. Ads for online trading firms feed people's hopes and fears by making them think they have control over markets and that trading is fun and profitable.