We study multi-unit auctions for bidders that have a budget constraint, a situation very common in practice that has received relatively little attention in the auction theory literature. Our main result is an impossibility: there is no deterministic auction that (1) is individually rational and...

We consider the makespan-minimization problem on unrelated machines in the context of algorithmic mechanism design. No truthful mechanisms with non-trivial approximation guarantees are known for this multidimensional domain. We study a well-motivated special case (also a multidimensional...

We analyze a simultaneous ascending auction with anonymous item prices, for two items that are substitutes. This popular format entails increased opportunities for coordination among bidders, since bids are observable and can be used as signaling. This has happened, e.g., in the Netherlands 3G...

A mediator is a reliable entity which plays on behalf of the players who give her the right to play. The mediator acts in a pre-specified way based on messages received from the players. However, a mediator cannot enforce behavior; that is, players can play in the game directly without the...