In this study, Professors Chih-Ling Tsai and co-authors Ning Zhu from the Shanghai Advanced Institute of Finance and Ming-Chun Wang from National Chengchi University use a data set from market participants in the Taiwan Stock Exchange Capitalization Weighted Stock Index options markets to demonstrate a strong positive relationship between prior trading outcomes and subsequent risk taking. In particular, investors in this market take above-average risks in afternoon trading after morning gains.

The phenomenon is prevalent in all three types of market makers’ accounts and across different types of market participants. This study’s findings are consistent with the argument that prior outcomes affect subsequent risk taking through a relationship that is sensitive to the model parameters (i.e., expected return, trading period, and curvature of the value function), because prospect theory can predict both increased and decreased levels of subsequent risk taking.