Overconfidence among professional investors: Evidence from mutual fund managers

We examine overconfidence among equity mutual fund managers. While overconfidence has been extensively documented among retail investors, evidence from professional investors is scarce. Consistent with theories of overconfidence, we find that fund managers trade more after good past performance. The higher trading activity after good performance is driven by individual portfolio performance, while the market performance has no significant impact. We find no spillover effects from one good performing fund on the turnover ratios of the other funds the same manager manages, suggesting that managerial overconfidence is task-specific. Our results are not consistent with an increase in trading activity by fund managers when rational Bayesian learning has informed them about their abilities.