An optimal contract may involve randomization when the agents differ in their attitudes towards risk, so that randomization enables the principal to relax the incentive constraints. The paper provides a necessary and sufficient condition for local random deviations to be welfare improving in a...

A government agency delegates to a provider (hospital, medical gatekeeper, school, social worker) the decision to supply a service or treatment to individual recipients. The agency does not perfectly know the distribution of individual treatment costs in the population. The single-crossing...

A government agency delegates to a provider (hospital, medical gatekeeper, school, social worker) the decision to supply a service or treatment to individual recipients. The agency does not perfectly know the distribution of individual treatment costs in the population. The single-crossing...

This note characterizes the optimal base for commodity taxation in the presence of administrative fixed costs varying across goods. For low tax rates, the optimal base only comprises commodities whose discouragement index is greater than the ratio of their administrative costs to the tax they...

We study how asymmetric information affects the set of rationalizable solutions in a linear setup where the outcome is determined by forecasts about this same outcome. The unique rational expectations equilibrium is also the unique rationalizable solution when the sensitivity of the outcome to...

We study rationalizable solutions in a linear asymmetric Cournot oligopoly. We show that symmetry across firms favors multiplicity of rationalizable solutions: A merger (implying a greater asymmetry across firms) makes out-of-equilibrium behavior less likely and should dampen &lquo;coordination&rquo;...

The paper identifies a necessary and sufficient condition for a deterministic local optimum to be locally improved upon by a stochastic deviation. When this condition is satisfied, a method to construct the stochastic allocations that increase the objective is provided. This technique is applied...

This note characterizes, in a partial equilibrium economy with a single agent, which commodities should be taxed whenever there is only one available tax rate. We show that commodities with low price elasticities should be imposed; luxuries are eventually exempted.

This paper analyzes the optimal structure of indirect taxation when the number of available tax rates is smaller than the number of taxable commodities. Such a constraint requires to choose the levels of tax rates and the groups of commodities that will be taxed at equal rates (or exempted). In...

L'idée qu'une baisse des cotisations sociales compensée par une hausse de la TVA pourrait favoriser l'emploi et la compétitivité fait l'objet de débats. Nous montrons ici qu'une telle mesure n'est pas neutre à long terme : à situation budgétaire inchangée, les effets des allégements de...