Different models of uncertainty aversion imply strikingly different economic behavior. The key to understanding these differences lies in the dichotomy between first-order and second-order ambiguity aversion which I define here. My definition and its characterization are independent of specific...

Consider managers evaluating their employees' performances. Should managers justify their subjective evaluations? Suppose a manager's evaluation is private information. Justifying her evaluation is costly but limits the principal's scope for distorting her evaluation of the employee. I show that...

I show that legal uncertainty, i.e., uncertainty about the legality of a specific action, has positive welfare effects. Legal uncertainty works as a screening device provided that the threshold of legality is uncertain. The uncertainty discourages controversial actions, while it encourages...