Agents' valuations are interdependent if they depend on the signals of all agents. Previous literature has claimed that with interdependent valuations and multidimensional, but independent, signals, efficient auction design is impossible. This paper shows that, on the contrary, it is always...

We study sequential and single-round uniform-price auctions with affiliated values. We derive symmetric equilibrium for the auction in which k1 objects are sold in the first round and k2 in the second round, with and without revelation of the first-round winning bids. We demonstrate that...

We study the repeated implementation of social choice functions in environments with complete information and changing preferences. We define dynamic monotonicity, a natural but nontrivial dynamic extension of Maskin monotonicity, and show that it is necessary and almost sufficient for repeated...

A mechanism implements a social choice correspondence f in mixed Nash equilibrium if at any preference profile, the set of all pure and mixed Nash equilibrium outcomes coincides with the set of f-optimal alternatives at that preference profile. This definition generalizes Maskin’s definition...

A mechanism implements a social choice correspondence f in mixed Nash equilibrium if at any preference profile, the set of all pure and mixed Nash equilibrium outcomes coincides with the set of f-optimal alternatives at that preference profile. This definition generalizes Maskin’s definition...

A mechanism implements a social choice correspondence f in mixed Nash equilibrium if, at any preference profile, the set of all (pure and mixed) Nash equilibrium outcomes coincides with the set of f-optimal alternatives for all cardinal representations of the preference profile. Unlike Maskinʼs...

We study the gains from trade in a model with endogenously variable markups. We show that the pro-competitive gains from trade are large if the economy is characterized by (i) extensive misallocation, i.e., large ineciencies associated with markups, and (ii) a weak pattern of cross-country...

This paper studies full implementation problems in (pure and mixed) Nash equilibrium in finite environments. We restrict the designer to adopt<I>finite</I> mechanisms, thus ruling out integer games. We provide a condition, top-<I>D</I> inclusiveness, that together with set-monotonicity is sufficient for mixed...</i></i>