The theory of subjective expected utility (SEU) has been recently extended to allow ambiguity to matter for choice. We propose a notion of absolute ambiguity aversion by building on a notion of comparative ambiguity aversion. We characterize it for a preference model which encompasses some of...

We introduce and characterize axiomatically a general model of static choice under uncertainty, which is possibly the weakest model in which a separation of cardinal utility and a representation of beliefs is achieved. Most of the popular non-expected utility models in the literature are special...

We show that range convexity of beliefs, a 'technical' condition that appears naturally in axiomatizations of preferences in a Savage-like framework, imposes some unexpected restrictions when modelling ambiguity averse preferences. That is, when it is added to a mild condition, range convexity...