Governments must usually take policy decisions with an imperfect knowledge of the economic actors' type or the actors' effort level. These issues are addressed within the framework of classic adverse selection or moral hazard models. I discuss in this paper how would the government’s and the...

I study a mechanism design problem in which a designer allocates a single good to one of several agents, and the mechanism is followed by an aftermarket -- a post-mechanism game played between the agent who acquired the good and third-party market participants. The designer has preferences over...

We model an online display advertising environment in which "performance'' advertisers can measure the value of individual impressions, whereas "brand" advertisers cannot. If advertiser values for ad opportunities are positively correlated, second-price auctions for impressions can be...

We consider a general economy, where agents have private information about their types. Types can be multi-dimensional and potentially interdependent. We show that, if the interim distribution of types is common knowledge (the exact number of agents for each type is known), then a mechanism...

This paper shows that the possibility of collusion between an agent and a supervisor imposes no restrictions on the set of implementable social choice functions (SCF) and associated payoff vectors. Any SCF and any payoff profile that are implementable if the supervisor's information was public...

This paper considers a multi-period setting where a monopolist, with short-term commitment, rents one unit of a durable good to a single consumer in every period. The consumer's valuation constitutes his private information and remains constant over time. By using a mechanism design approach,...

This paper provides a complete characterization of equilibria in a game-theoretic version of Rothschild and Stiglitz's (1976) model of competitive insurance. I allow for stochastic contract offers by insurance firms and show that a unique symmetric equilibrium always exists. Exact conditions...

We study the mechanism design problem for a seller of an indivisible good in a setting where privately informed buyers can acquire additional information and refine their valuations for the good at a cost. For this setting, we propose optimal (revenue-maximizing) and efficient...

We completely characterize the set of second-best optimal “menus”of student-loan contracts in a simple economy with risky labour-market outcomes, adverse selection, moral hazard and risk aversion. The model combines structured student loans and an elementary optimal income-tax problem à la...

We decentralize incentive efficient allocations in large adverse selection economies by introducing a Walrasian market for mechanisms, that is, for menus of contracts. Facing a budget constraint, informed individuals purchase (lottery) tickets to enter mechanisms, while firms sell tickets and...