We study a classic mechanism design problem: How to organize trade between two privately informed parties. We characterize an optimal mechanism under selfish preferences and present experimental evidence that, under such a mechanism, a non-negligible fraction of individuals deviates from the...

A social choice function is robustly implemented if every equilibrium on every type space achieves outcomes consistent with it. We identify a robust monotonicity condition that is necessary and (with mild extra assumptions) sufficient for robust implementation.Robust monotonicity is strictly...

A social choice function is robustly implemented if every equilibrium on every type space achieves outcomes consistent with it. We identify a robust monotonicity condition that is necessary and (with mild extra assumptions) sufficient for robust implementation. Robust monotonicity is strictly...

When is a mechanism designer justified in only asking for ordinal information about preferences? Simple examples show that, even if the planner's goal (expressed by a social choice correspondence, or SCC) depends only on ordinal information, eliciting cardinal information may help with...

We introduce intention-based social preferences into a mechanism design framework with independent private values and quasilinear payoffs. For the case where the designer has no information about the intensity of social preferences, we provide conditions under which mechanisms which have been...

We introduce intention-based social preferences into mechanism design. We explore information structures that dier with respect to what is commonly known about the weight that agents attach to reciprocal kindness. When the designer has no information on reciprocity types, implementability of an...

We show that a solution to the problem of mechanism selection by an informed principal exists in a large class of environments with “generalized private values”: the agents’ payoff functions are independent of the principal’s type. The solution is an extension of Maskin and Tirole’s...

This paper generalizes a conceptual insight in dynamic contracting with quasilin- ear payoffs: the principal does not need to pay any information rents for extract- ing the agent’s “new” private information obtained after signing the contract. This is shown in a general model in which the...

This paper studies the optimal refund mechanism when an uninformed buyer can privately acquire information about his valuation over time. In principle, a refund mechanism can specify the odds that the seller requires the product returned while issuing a (partial) refund, which we call stochastic...