We study a decision-maker who follows the Savage axioms. We show that if s(he) is able to take unobservable actions which influence the probabilities of outcomes then it can appear to an outsider as if his/her subjective probabilities are non-additive. Implications for multi-period decisions are...

We examine the effect of Knightian uncertainty in a simple model of public good provision. We find that uncertainty may reduce free-riding if utility is concave or there are decreasing returns to scale in the production of public goods. Comparative statics analysis shows that increases in...

This paper introduces E-capacities as a representation of beliefs which incorporates objective information about the probability of events. It can be shown that the Choquet integral of an E-capacity is the Ellsberg representation. The paper further explores properties of this representation of...