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...

We propose a new decision criterion under risk in which people extract both utility from anticipatory feelings ex ante and disutility from disappointment ex post. The decision maker chooses his degree of optimism, given that more optimism raises both the utility of ex ante feelings and the risk...

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...

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 effect of increasing (decreasing) equilibrium prices under...

This paper explores the relationship between dynamic consistency and the existing notions of unambiguous events for Choquet expected utility preferences. A decision maker is faced with an information structure represented by a filtration. We show that the decision maker's preferences respect...