Empirical Linkages between Trading Volume and Stock Markets Shocks: When Sentiments Drive Investors' Behavior.

In this paper, we examine the impact of investor psychological state on their trading volume for the US stock market using a VECM model for the period from July 1987 to May 2014. We propose alternative specifications for investors' sentiment considering their optimistic and pessimistic states. We find that during pessimistic periods, investors' are extensively alerted. In optimistic and normal periods, they are less attentive. [ABSTRACT FROM AUTHOR]