In [7] Ghirardato, Macheroni and Marinacci (GMM) propose a method for distinguishing between perceived ambiguity and the decision-maker's reaction to it. They study a general class of preferences which they refer to as invariant biseparable. This class includes CEU and MEU. They axiomatize a...

We show that the monotone continuity condition introduced by Arrow (1970) is the behavioral counterpart of countable additivity and weak compactness of the set of priors in a maxmin expected utility model. This generalizes Arrow's original result, who considered the special case of a singleton...

We show that the monotone continuity condition introduced by Arrow (1970) is the behavioral counterpart of countable additivity and weak compactness of the set of priors in a maxmin expected utility model. This generalizes Arrow's original result, who considered the special case of a singleton...

In a multiple priors model á la Gilboa and Schmeidler (1989), we provide necessary and sufficient behavioral conditions ensuring the countable additivity and non-atomicity of all priors. Copyright Springer-Verlag Berlin/Heidelberg 2005

We show that the monotone continuity condition introduced by Villegas (1964) and Arrow (1970) is the behavioral counterpart of countable additivity (and relative weak compactness) in a multiple priors model. This generalizes their original result, in which the special case of a singleton set of...