A theory of incomplete preferences under uncertainty is proposed, according to which a decision maker’s preferences are indeterminate if and only if her confidence in the relevant beliefs does not match up to the stakes involved in the decision. The author uses the model of confidence in...

One apparent reason for deferring a decision – abstaining from choosing, leaving the decision open to be taken by someone else, one’s later self, or nature – is for lack of sufficient confidence in the relevant beliefs. This paper develops an axiomatic theory of decision in situations...

This paper studies the costs and benefits of delegating decisions to superiorly informed agents relative to the use of rigid, non discretionary contracts. The main focus of the paper lies in the analysis of the costs of delegation, primarily agency costs, versus their benefits, primarily the...

We consider an aggregation scheme of opinions expressed through different probability distributions or multiple priors decision model. The decision-maker adopts entropy maximization as a measure of risk diversification and a rational form of prudence for valuing uncertain outcomes. We show a new...

This paper experimentally tests whether violations of Savage's (1954) subjective expected utility theory decrease if the ambiguity of an uncertain decision situation is reduced through statistical learning. Because our data does not show such a decrease, existing models which formalize ambiguity...

This paper unifies and extends the recent axiomatic literature on minimax regret. It compares several models of minimax regret, shows how to characterize the according choice correspondences in a unified setting, extends one of them to choice from convex (through randomization) sets, and...

Many real-life decisions have to be taken on the basis of probability judgements of which the decision maker is not entirely sure. This paper develops a decision rule for taking such decisions, which incorporates the decision makerʼs confidence in his probability judgements according to the...

Most existing decision-making models assume that choice behavior is based on preference maximization even when the preferences are incomplete. In this paper we study an alternative approach – “justifiable choice”: each agent has several preference relations (“justifications”), and she...

We introduce two subclasses of convex measures of risk, referred to as entropy coherent and entropy convex measures of risk. We prove that convex, entropy convex and entropy coherent measures of risk emerge as certainty equivalents under variational, homothetic and multiple priors preferences,...

The problem of how to rationally aggregate probability measures occurs in particular (i) when a group of agents, each holding probabilistic beliefs, needs to rationalise a collective decision on the basis of a single ‘aggregate belief system’ and (ii) when an individual whose belief system...