Define the riskiness of a gamble as the reciprocal of the absolute risk aversion (ARA) of an individual with constant ARA who is indifferent between taking and not taking that gamble. We characterize this index by axioms, chief among them a “duality” axiom which, roughly speaking, asserts...

Consider a finite data set where each observation consists of a bundle of contingent consumption chosen by an agent from a constraint set of such bundles. We develop a general procedure for testing the consistency of this data set with a broad class of models of choice under risk and under...

We develop a nonparametric procedure, called the lattice method, for testing the consistency of contingent consumption data with a broad class of models of choice under risk and under uncertainty. Our method allows for risk loving and elation seeking behavior and can be used to calculate, via...

Robust control theory is a tool for assessing decision rules when a decision maker distrusts either the specification of transition laws or the distribution of hidden state variables or both. Specification doubts inspire the decision maker to want a decision rule to work well for a ∅ of models...

This paper states necessary and sufficient conditions for the existence, uniqueness, and updating according to Bayes´ rule, of subjective probabilities representing individuals´ beliefs. The approach is preference based, and the result is an axiomatic subjective expected utility model of...

This paper develops an axiomatic theory of decision making under uncertainty that dispenses with the state space. The results are subjective expected utility models with unique, action-dependent, subjective probabilities, and a utility function defined over wealth-effect pairs that is unique up...

This paper presents axiomatic models of decision making under uncertainty that avoid the use of a state space. The models are (a) general subjective expected utility theory with action-dependent subjective probabilities and effect-dependent utilities (the cases of effect-independent preferences...

Despite extensive studies, the nature of risk attitudes remains a vigorously discussed question in economics and psychology. In expected utility theory, attitudes towards risk originate from changes in marginal utility. Cumulative prospect theory (CPT) adds an additional dimension: the weighting...

Experimental research on decision making under risk has until now always employed choice data in order to evaluate the empirical performance of expected utility and the alternative nonexpected utility theories. The present paper performs a similar analysis which relies on pricing data instead of...

This paper analyzes decisions on emissions of a stock pollutant under uncertainty in a two period model. Decisions are based on a weighted average of expected utility (EU) and the MaxiMin criterion. I first show that more weight on the worst case (less weight on EU) may lead to increased first...