In auction and mechanism design, Myerson's classical regularity condition is often too weak for a quantitative analysis of performance. For instance, ratios between revenue and welfare, or sales probabilities may vanish at the boundary of Myerson regularity. This paper introduces L-regularity as...

In mechanism design, Myerson regularity is often too weak for a quantitative analysis of performance. For instance, ratios between revenue and welfare, or sales probabilities may vanish at the boundary of Myerson regularity. This paper therefore explores the quantitative version of Myerson...

It is tricky to design local regulations on global externalities, especially so if firms are mobile. We show that when costs and outside options are firms' private information, the threat of firm relocation leads to local regulations that are stricter, not looser. This result is general and...

I study a mechanism design problem of allocating a single good to an agent when the mechanism is followed by a post-mechanism game (aftermarket) played between the agent and a third-party. The aftermarket is beyond the direct control of the designer. However, she can influence the information...

A mediator, with no prior information and no control over the market protocol, attempts to redesign the information structure in the market by running an information intermediation mechanism with transfers that first elicits information from an agent, and then discloses information to another...

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...

We consider a budget-constrained mechanism designer who selects an optimal set of projects to maximize her utility. Projects may differ in their value for the designer, and their cost is private information. In this allocation problem, the quantity of procured projects is endogenously determined...

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.

We study a problem of optimal auction design in the realistic case in which the players can collude both on the way they play in the auction and on their participation decisions. Despite the fact that the principal's opportunities for extracting payments from the agents in such a situation are...

We give a sufficient condition on the type space for revenue equivalence when the set of social alternatives consists of probability distributions over a finite set. Types are identified with real-valued functions that assign valuations to elements of this finite set, and the type space is...