An Empirical Investigation of Herd Behavior:Evidence from TSE

Herding behavior is among the most noticed biases in behavioral finance. This bias implies that investors unknowingly neglect personal information and analyses; instead they tend to follow other investors or the whole market. Using Tehran Exchange stocks transactions data, this study empirically examines herding behavior in this market. Two models based on cross-sectional deviation of stock returns and another model based on beta in state-space structure are utilized in our research. The sample covers 21,112 weekly returns and transaction volumes observations from April 2005 to April 2011. Our findings indicate that participants often lack independent investment decisions; i.e. they prefer following other investors’ decisions to taking an independent approach. This confirms that herding behavior exists in Tehran Stock Exchange. Moreover, evaluating comparative power of our three models suggests that the model based on beta is more powerful in explaining herding behavior than the other model.