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 analyzes the optimal contract for a consumer to procure a credence good from an expert when (i) the expert might misrepresent his private information about the consumer’s need, (ii) the expert might not choose the requested service since his choice of treatment is non-observable,...

This note establishes a revelation principle in terms of payoff for deterministic mechanisms under ex-post constraints: the maximal payoff implementable by a feasible deterministic mechanism can also be implemented by a feasible deterministic direct mechanism.

In many trade environments - such as online markets - buyers fully learn their valuation for goods only after contracting. I characterize the buyer-optimal ex-ante information in such environments. Employing a classical sequential screening framework, I find that buyers prefer to remain...

This paper introduces the matched-bet mechanism. The matched bet is an easily applicable and strictly budget-balanced mechanism that aims to help people overcome time-inconsistent behavior. I show theoretically that offering a matched bet helps both sophisticated and naive procrastinators to...

This paper studies mechanism design under the level-k solution concept. The first result gives a general necessary condition for a social choice rule to be level-k implementable. In some environments, this necessary condition is equivalent to Bayesian incentive compatibility, making level-k...

This paper provides a micro-foundation for approximate incentive compatibility using ambiguity aversion. In particular, we propose a novel notion of approximate interim incentive compatibility, approximate local incentive compatibility, and establish an equivalence between approximate local...

We study optimal mechanisms for a utilitarian designer who seeks to assign a finite number of goods to a group of ex ante heterogeneous agents with unit demand. The agents have heterogeneous marginal utilities of money, which may naturally arise in environments where agents have different wealth...