Oulu Business School

Empirical studies have analyzed how investors trade and perform in the financial markets. The studies show that rational trading needs do not explain the excessive manner of trading shown by the investors. Theoretical models offer overconfidence as one of the explanations for irrational trading behavior. Overconfidence is a psychological trait, argued to cause the investors to misinterpret useful information, which leads to an increase in trading activity and hurts their performance. In this study we analyze over 1.5 million Finnish trading records from the beginning of 1995 to the end of 2010. We evaluate the differences in trading behavior between males and females and with investors of diverse ages. We find that men trade securities more frequently and with higher turnover than females. Consistently with our reference studies we find that the level of turnover decreases as the investors age. We also analyze the profitability effects of trading by calculating raw returns and abnormal returns. The abnormal returns are adjusted with a passive benchmark portfolio. Earlier studies show that the more active trading of males reduces their abnormal returns. Our abnormal return ratios do not support this finding. However, we find consistently that the raw returns are higher for females than males. Females also hold portfolios with lower volatility than males. Finally, we find consistently with the models of overconfidence by Odean (1998b) and Gervais and Odean (2001) that the trading skill seems to get better with experience. Older investors receive higher raw returns and trade less, resulting in lower portfolio turnover. The transition in trading behavior may be an outcome of learning.