Marie-José Avenier (CERAG, Grenoble) réagit sur les questions épistémologiques soulevées dans le précédent numéro en défendant le paradigme constructiviste. Pour elle, il s'agit bien d'un paradigme même si elle distingue différents types de constructivisme, fondé sur des hypothèses...

Les recherches qualitatives se veulent souvent exploratoires : elles entendent inventer des concepts, proposer de nouvelles notions et théories. Dans le même temps, pour interpréter les données, elles manient des concepts existants. Mais bien souvent, les notions utilisées ou proposées...

Dans un livre récent, How professors think, Michèle Lamont (Harvard University) analyse la manière dont des chercheurs de différentes disciplines, réunis dans des comités, construisent un jugement collectif en sélectionnant des projets de recherche à financer. L'intérêt de l'ouvrage...

The evaluation of social risk equity for alternative probability distributions over the potential sets of fatalities is analyzed axiomatically. Fishburn and Straffin [Equity considerations in public risks valuation, Operatons Research 37 (1999), 229-239] have identified a necessary and...

This paper presents an axiomatic model of decision making under uncertainty which incorporates objective but imprecise information. Information is assumed to take the form of a probability-possibility set, that is, a set $P$ of probability measures on the state space. The decision maker is told...

We study the Full Bayesian Updating rule for convex capacities. Following a route suggested by Jaffray (1992), we define some properties one may want to impose on the updating process, and identify the classes of (convex and strictly positive) capacities that satisfy these properties for the...

This paper presents an axiomatic model of decision making which incorporates objective but imprecise information. We axiomatize a decision criterion of the multiple priors (or maxmin expected utility) type. The model achieves two primary objectives. First, it explains how subjective belief...

We develop an axiomatic approach to decision under uncertainty that explicitly takes into account the information available to the decision maker. The information is described by a set of priors and a reference prior. We define a notion of imprecision for this informational setting and show that...

We propose an extension of Harsanyi's Impartial Observer Theorem based on the representation of ignorance as the set of all possible probability distributions over individuals. We obtain a characterization of the observer's preferences that, under our most restrictive conditions, is a convex...

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...