Epstein (2009) describes three Ellsberg-style thought experiments and argues that they pose difficulties for the smooth ambiguity model of decision making under uncertainty developed by Klibanoff, Marinacci and Mukerji (2005).  We revisit these thought exeperiments and find, to the contrary,...

Are foundations of models of ambiguity-sensitive preferences too flawed to be usefully applied to economic models?  Al-Najjar and Weinstein (2009) say such is indeed the case.  In this paper, first, we point out that many of the key arguments by Al-Najjar and Weinstein do not apply to quite a...

We examine a variety of preference-based definitions of ambiguous events in the context of the smooth ambiguity model.  We first consider the definition proposed in Klibanoff, Marinacci, and Mukerji (2005) based on the classic Ellsberg two-urn paradox (Ellsberg (1961)), and show that it...

We investigate what it means for one act to be more ambiguous than another. The question is evidently analogous to asking what makes one prospect riskier than another, but beliefs are neither objective nor representable by a unique probability. Our starting point is an abstract class of...

We define a behavioral concept of relevance in the context of decision making under uncertainty.  We argue that this concept provides a sensible answer to the question "What probabilistic environments do an individuals' preferences reveal as mattering to her decisions?" under a symmetry...

According to the Description-Experience gap (DE gap), people act as if overweighting rare events when information about those events is derived from descriptions but as if underweighting rare events when they experience them through a sampling process. While the is now clear evidence that the DE...

The Description-Experience gap (DE gap) is widely thought of as a tendency for people to act as if overweighting rare events when information about those events is derived from descriptions but as if underweighting rare events when they experience them through a sampling process. While there is...

Abstract This paper concerns the interpretation of equilibrium in non-additive beliefs in two-player normal form games. We argue that such equilibria involve beliefs and actions which are consistent with a lack of common knowledge of the game. Our argument rests on representation results which...

We investigate what it means for one act to be more ambiguous than another. The question is evidently analogous to asking what makes one prospect riskier than another, but beliefs are neither objective nor representable by a unique probability. Our starting point is an abstract class of...