Stochastic and deterministic menus in common agency games

In this note, we argue that in Common Agency games the restriction todeterministic menus is critical. We give an simple example, with complete information and no moral hazard,where an equilibrium is not robust to the introduction of stochastic menus.Delegation Principle

Labor Mobility and Income Tax Competition

This paper provides a model of nonlinear income taxation in a context of international mobility. We consider two identical countries, in which each government chooses non-cooperatively redistributive taxes. It is shown that when skilled workers can move at low cost, the income taxation does not involve distortions. When the cost to move becomes high for skilled workers, taxation policy is less redistributive but qualitatively similar to the taxation policy in autarky. Moreover, the mobility of the unskilled workers does not affect the income taxation when both countries have Rawlsian objectives.Fiscal Competition, Labor Mobility, Optimal Taxation, Mechanism Design

The Biais-Martimort-Rochet equilibrium with direct mechanisms

In this note we show that the equilibrium characterized by Biais, Martimort and Rochet (Econometrica, 78, 2000) could have been characterized by using direct mechanisms.Common Agency, Revelation Principle, Direct Mechanisms, Nonlinear Prices

Optimal Taxation and In-Kind Redistribution

Within a framework of optimal taxation a la Mirrlees, we add a new heterogeneity between the individuals who differ not only on their marginal productivity, but also on their initial endowment in a good which is interpreted as an aggregate consumption. We consider other goods in the economy whose characteristics (impossibility of resale, impossibility of increasing on the private market a public supply) are those of the hospital care or education for example. We show that one can justify the public supply of this good on an economic criterion of efficiency, in spite of an assumption of separability of work and consumption in the utility function of the individuals.

Direct Mechanisms, Menus and Latent Contracts

In common agency games, one cannot characterize all equilibria by considering only direct mechanisms. In an attempt to overcome this difficulty, Peters [Econometrica, 2001]and Martimort and Stole [Econometrica, 2002] identified a class of indirect mechanisms (namely, menus) which are able to characterize every equilibrium. Unfortunately, menus are difficult to handle, and several methodologies have been proposed in the literature. Here, it is shown that, even if authors consider menus rather than simpler mechanisms, many equilibria described in the literature could have been characterized by direct incentive compatible mechanisms. Use of more sophisticated mechanisms was not necessary in these cases

Multiple Lending and Constrained Efficiency in the Credit Market

This paper studies the relationship between competition and incentives in an economy with financial contracts. We concentrate on non-exclusive credit relationships, those where an entrepreneur can simultaneously accept more than one contractual offer. Several homogeneous lenders compete on the contracts they offer to finance the entrepreneur's investment project. We model a common agency game with moral hazard, and characterize its equilibria. As expected, notwithstanding the competition among the principals (lenders), non-competitive outcomes can be supported. In particular, positive profit equilibria are pervasive. We then provide a complete welfare analysis and show that all equilibrium allocations turn out to be constrained Pareto efficient.

Information Revelation in Competing Mechanism Games

We consider multiple-principal multiple-agent games of incomplete information. In this context, we identify a class of direct and incentive compatible mechanisms: each principal privately recommends to each agent to reveal her private information to the other principals, and each agent behaves truthfully. We show that there is a rationale in restricting attention to this class of mechanisms: if all principals make use of direct incentive compatible mechanisms, there are no incentives to unilaterally deviate towards more sophisticated mechanisms. We develop two examples to show that private recommendations are a key element of our construction, and that the restriction to direct incentive compatible mechanisms is not sufficient to provide a complete characterization of equilibria.Incomplete information, competing mechanisms, information revelation