We provide possibility results on the aggregation of beliefs and tastes for Monotone, Bernoullian and Archimedian preferences of Cerreia-Vioglio, Ghirardato, Maccheroni, Marinacci and Siniscalchi (2011). We propose a new axiom, Unambiguous Pareto Dominance, which requires that if the unambiguous...

We investigate the empirical relation between ambiguity aversion, risk aversion and portfolio choices. We match administrative panel data on portfolio choices with survey data on preferences over ambiguity and risk. We report three main findings. First, conditional on participation, ambiguity...

We review recent advances in the field of decision making under uncertainty or ambiguity.

We provide a general method for extending fair social preferences defined for riskless economic environments to the context of risk and uncertainty. We apply the méthod to the problems of managing unemployment allowances (in the context of macroeconomic fluctuations) and catastrophic risks (in...

The aim of this paper is to study the optimal nuclear waste burial policy under an uncertainty : the possibility that an accident might occur in the future. The framework is an optimal growth model with pollution disutility. We show, under some conditions on the waste burial policy, that nuclear...

The Word Summit on Sustainable Development (Johannesburg, 2002) encouraged the application of the ecosystem approach by 2010. In this perspective, we propose a theoretical management framework that deals jointly with i) ecosystem dynamics, ii) conflicting issues of production and preservation...

Theories of justice in the spirit of Rawls and Harsanyi argue that fair-minded people should aspire to make choices for society as if in the original position, that is, behind a veil of ignorance that prevents them from knowing their own social positions. In this paper, we provide a fairly...

We provide a general theorem on the aggregation of preferences under uncertainty. We study, in the Anscombe-Aumann setting a wide class of preferences, that includes most known models of decision under uncertainty (and state-dependent versions of these models). We prove that aggregation is...

This paper analyzes optimal wage contracting assuming agents are not subjective expected utility maximizers but are, instead, ambiguity (or uncertainty) averse decision makers who maximize Choquet expected utility. We show that such agents will choose not to include any indexation coverage in...

We provide a model of decision making under uncertainty in which the decision maker reacts to imprecision of the available data. Data is represented by a set of probability distributions. We axiomatize a decision criterion of the maxmin expected utility type, in which the revealed set of priors...