In this paper we consider the effect of ambiguity on the private provision of public goods. Equilibrium is shown to exist and be unique. We examine how provision of the public good changes as the size of the population increases. We show that when there is uncertainty there may be less...

The concept of a non-extreme-outcome-additive capacity (neo-additive capacity ) is introduced. Neo-additive capacities model optimistic and pessimistic attitudes towards uncertainty as observed in many experimental studies. Moreover, neo-additive capacities can be applied easily in economic...

In Ghirardato, Macheroni and MArcinaccri (GMM) propose a method for distinguishing between percieved ambiguity and the decision-maker's reaction to it. They study a general class of preferences which includes CEU and a-MEU and axiomatise a subclass of a-MEU preferences. We show that for Hurwicz...

This paper studies how updating affects ambiguity attitude. In particular we focus on generalized Bayesian updating of the Jaffray–Philippe sub-class of Choquet Expected Utility preferences. We find conditions for ambiguity attitude to be the same before and after updating. A necessary and...

We present a non-technical account of ambiguity in strategic games and show how it may be applied to economics and social sciences. Optimistic and pessimistic responses to ambiguity are formally modelled. We show that pessimism has the e?ect of increasing (decreasing) equilibrium prices under...