Cet article a pour objet d'analyser les strategies de prix d'une firme en monopole sur son marche domestique et en duopole sur un autre marche europeen. Le produit est vendu par le biais d'un reseau de distribution exclusive dans les deux pays. La firme peut etre concurrencee sur son propre...

We shape a formal framework for distinguishing the behaviour of constructive and non-constructive polynomial time approximation algorithms for NP optimization problems. We introduce a new class, called SubNPO, that includes NPO and also some other problems used in recent works.

We draw a rough shape of a general formal framework for polynomial approximation theory which encompasses the existing one by allowing the expression of new types of results. We show how this framework incorporates all the existing approximation results and, moreover, how new types of results...

We consider a stylized bond-equity economy, which though incomplete per se, has a rich enough set of assets available for trade such that given standard assumptions about behavior under uncertainty, the equilibrium allocation would arbitrarily approximate a complete market allocation. We show,...

Nous exposons dans cet article les avancees de la theorie de la decision en environnement incertain au cours des vingt dernieres années. plus precisément, nous partons des modeles d'esperance (objective et subjective) d'utilite pour ensuite en presenter les generalisations recentes.

This paper explores the consequences of non-additive expected utility on risk-sharing and equilibrium in a general equilibrium set-up. We establish that convexity of an agent's preferences (or strong uncertainty aversion) is equivalent to the convexity of his capacity and concavity of his...

We prove an integral representation theorem for functionals fulfilling some continuity conditions. These functionals satisfy a weaker condition than additivity, namely additive comonotonicity and do not need to be monotonic.

A usual argument in finance refers to no arbitrage opportunities for the positivity of the bid-ask spread. Here we follow the decision theory approach and show that if positivity of the bid-ask spread is identified with strong risk aversion for an expended utility market-marker, this is no...

Cumulative prospect theory was introduced by Tversky and Kahneman to combine the empirical realism of their original prospect theory with the theoretical advantages of rank-dependent utility. Preference axiomatizations were provided in several papers. All exosting axiomatizations, however, only...

Cette note considere un eeconomie d'echange a deux periodes dans laquelle les dotations sont incertaines. En plus de cette incertitude economique, existe une incertitude pesant sur les paiements des actifs financiers. Les agents ont des croyances non-additives en ce qui concerne l'incertitude...