It has been shown by Maskin and Tirole (1990, proposition 11) that with quasi-linear preferences and private values, an informed principal neither gains nor loses if her private information is revealed before contracting takes place. The note shows that this result may not hold when the agent...

This paper studies communication mechanisms for two players with symmetric single-peaked preferences. The peaks are privately known and drawn from a uniform distribution before the agents take a collective decision. While for the general setting Moulin (1980) characterized all strategy-proof...

We investigate the issue of implementation via individually rational ex-post budget-balanced Bayesian mechanisms. We demonstrate that all social choice rules that generate a nonnegative ex-ante surplus, including ex-post efficient ones, can generically be implemented via such mechanisms for any...

In a class of informed principal problems with common values often used in applications we de…fine a particular mechanism which we call the assured allocation. It is always undominated, i.e. efficient among the different types of the principal. We show it is a perfect Bayesian equilibrium...