Rational herd behavior and informationally efficient security prices have long been considered to be mutually exclusive but for exceptional cases. In this paper we describe the conditions on the underlying information structure that are necessary and sufficient for informational herding and...

We are the first paper to analyze and confirm the existence and extent of rational informational herding and rational informational contrarianism in a financial market experiment, and to compare and contrast these with the equivalent irrational phenomena. In our study, subjects generally behave...

Herding and contrarian behavior are often-cited features of real-world financial markets. Theoretical models of continuous trading that study herding and contrarianism, however, usually do not allow traders to choose when to trade or to trade more than once. We present a large-scale experiment...