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 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...