Informed Trading Behavior of Institutions and Individuals around Earnings Announcements

This study constructs the institutional- and individual-based probability of informed trading (PIN) by adjusting Easley, Hvidkjaer and O'Hara (2002) and investigates the impact of the informed trading behaviors of institutions and individuals on the post-announcement drift around the earnings announcement. The differences between this study and the previous literatures lie in that the investor types of informed traders are distinguished as institutions and individuals. Besides, the trading date effect is considered to examine the informed trading behaviors. The findings show that the informed trading behaviors of institutions and individuals can be distinguished. If there are informed traders involves in the stocks, the cumulative abnormal returns after the earnings announcement may be higher than the other stocks with no informed traders. Some individuals may possess relevant information that may prompt them to trade prior to or after the earnings announcement. The findings of the study may contribute to the government regulations and portfolio selections