We study the problem of elicitation of subjective beliefs of an agent when the beliefs are ambiguous (the set of beliefs is a non-singleton set) and the agent's preference exhibits ambiguity aversion; in particular, as represented by alpha-maxmin preferences. We construct a direct revelation...

Raiffa (1961) criticizes ambiguity-averse preferences by claiming that hedging is possible with randomization of choices. We argue that the timing of randomization is crucial for hedging. Ex-ante randomizations, which are randomizations before a state is realized, could provide only ex-ante...

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...

We propose a model of instrumental belief choice under loss aversion. When new information arrives, an agent is prompted to abandon her prior. However, potential posteriors may induce her to take actions that generate a lower utility in some states than actions induced by her prior. These losses...

We introduce a model of random ambiguity aversion. Choice is stochastic due to unobserved shocks to both information and ambiguity aversion. This is modeled as a random set of beliefs in the maxmin expected utility model of Gilboa and Schmeidler (1989). We characterize the model and show that...

The preference reversal phenomenon is one of the most important, long-standing, and widespread anomalies contradicting economic models of decisions under risk. It describes the robust observation of frequent "standard reversals" where long-shot gambles are valued above moderate ones but then the...

We propose a class of multiple-prior representations of preferences under ambiguity where the belief the decision-maker (DM) uses to evaluate an uncertain prospect is the outcome of a game played by two conflicting forces, Pessimism and Optimism. The model does not restrict the sign of the DM's...

This paper studies a problem of choice under uncertainty in which a decision-maker's (DM) choices randomly map to consumption outcomes. The primitive is a binary relation on menus, where a menu is a set of possible ex post outcomes. After the DM selects a menu, nature (not the DM) makes a...

Two of the most well known regularities observed in preferences under risk and uncertainty are ambiguity aversion and the Allais paradox. We study the behav- ior of an agent who can display both tendencies simultaneously. We introduce a novel notion of preference for hedging that applies to both...