A competition authority has an objective, which specifies what output profile firms need to produce as a function of production costs. These costs change over time and are only known by the firms. The objective is implementable if inequilibrium, the firms cannot collude on their reports to the...

I study a sequential first-price auction where two items are sold to two bidders with private binary valuations. A seller, prior to the second auction, can publicly disclose some information about the outcome of the first auction. I characterize equilibrium strategies for various disclosure...

We study repeated implementation in a model with overlapping generations of agents.It is assumed that the preferences of agents do not change during their lifetime.A social choice function selects an alternative in each period as a function of the preferences of agents who are alive in that...

I consider the problem of assigning agents to indivisible objects, in which each agent pays a price for his object and all prices sum to a given constant. The objective is to select an assignment-price pair that is envy-free with respect to the agents' true preferences. I propose a simple...

We study optimal bidder collusion at first-price auctions when the collusive mechanism only relies on signals about bidders' valuations. We build on Fang and Morris (2006) when two bidders have low or high private valuation of a single object and additionally each receives a private noisy signal...

We present an extension to any finite complete information game with two players. In the extension, players are allowed to communicate directly and, additionally, send private messages to a simple, detail-free mediator, which, in turn, makes public announcements as a deterministic function of...

The existence of ex-ante strong incumbents may constitute a barrier to entry in auctions for goods such as licenses. Introducing inefficiencies that favor entrants is a way to induce entry and thus create competition. Designs such as the Anglo-Dutch auction have been proposed with this goal in...

Assuming constant marginal cost, it is shown that a switch from specific to ad valorem taxation has no effect on the critical discount factor required to sustain collusion. This result is shown to hold for Cournot oligopoly as well as for Bertrand oligopoly when collusion is sustained with...

A general version of the ZMW model of international tax competition is presented that confirms and extends the results of the existing literature about the choice of tax policy instruments in the symmetric case when the tax externality is positive for both countries. In the asymmetric case when...