The paper provides a specification of belief systems for models of large economies with anonymity in which aggregate states depend only on cross-section distributions of types. For belief systems satisfying certain conditions of mutual absolute continuity, the paper gives a necessary and...

The paper studies efficient public-good provision in a model with private values whose distribution depends on a macro shock; conditionally on this shock, values are independent and identically distributed. A generalization of the Bayesian mechanism of d'Aspremont and Gérard-Varet is shown to...

I consider a seller selling a good to bidders with two-dimensional private information: their valuation for a good and their characteristic. While valuations are non-verifiable, characteristics are partially verifiable and convey information about the distribution of a bidder’s valuation. I...

This paper studies the optimal mechanisms for a seller with imperfect commitment who puts up for sale one individual unit per period to a single buyer in a dynamic game. The buyer's willingness to pay remains constant over time and is his private information. In this setting, the seller cannot...

In mechanism design with (partially) verifiable information, the revelation principle holds if allocations are modelled as the Cartesian product of outcomes and verifiable information, giving rise to evidence-contingent mechanisms. Consequently, incentive constraints characterize the...

We study a multi-dimensional collective decision under incomplete information. Agents have Euclidean preferences and vote by simple majority on each issue (dimension), yielding the coordinate-wise median. Judicious rotations of the orthogonal axes -- the issues that are voted upon -- lead to...

I study a persuasion game between a privately informed agent and a decision maker (DM) who can imperfectly verify the statements made by the agent by observing a signal that is correlated with the agent's information. I find that whether or not the DM benefits from communicating with the agent...

We consider robust virtual implementation, where robustness is the requirement that implementation succeed in all type spaces consistent with a given payoff type space as well as with a given space of first-order beliefs about the other agents’ payoff types. This last bit, which constitutes...

Suppose that the goals of a society can be summarized in a social choice rule, i.e., a mapping from relevant underlying parameters to final outcomes. Typically, the underlying parameters (e.g., individual preferences) are private information to the agents in society. The implementation problem...

For an incomplete-information model of public-good provision with interim participation constraints, we show that efficient outcomes can be approximated, with approximately full surplus extraction, when there are many agents and each agent is informationally small. The result holds even if...