We document economically large cross-sectional differences in the before- and after-fee returns earned by speculative traders by analyzing day traders in Taiwan from 1992 to 2006. We sort day traders based on their returns in year y and analyze their performance in year y+1; the 500 top-ranked...

We analyze 1,607 investors who switched from phone-based to online trading during the 1990s. Those who switch to online trading perform well prior to going online, beating the market by more than 2% annually. After going online, they trade more actively, more speculatively, and less profitably...

Individual investor trading results in systematic and economically large losses. Using a complete trading history of all investors in Taiwan, we document that the aggregate portfolio of individuals suffers an annual performance penalty of 3.8 percentage points. Individual investor losses are...