Every agent reports his willingness to pay for one unit of a good. A mechanism allocates goods and cost shares to some agents. We characterize the group strategyproof (GSP) mechanisms under two alternative continuity conditions interpreted as tie-breaking rules. With the maximalist rule (MAX) an...

I examine a contest with identity-dependent rules in which contestants are privately informed and ex ante heterogeneous. A contestant may suffer from a handicap or benefit from a head start. The former reduces the contestantʼs score by a fixed percentage; the latter is an additive bonus....

We study a sealed-bid auction between two bidders with asymmetric independent private values. The two bidders own asymmetric shares in a partnership. The higher bidder buys the lower bidderʼs shares at a per-unit price that is a convex combination of the two bids. The weight of the lower bid is...

We characterize the surplus-maximizing trading mechanism under two-sided incomplete information and interim individual rationality, when one party can make a value-enhancing specific investment. This mechanism exhibits a trade-off between providing investment incentives and inducing voluntary...

We consider a market for indivisible items with m buyers and m sellers. Traders privately know their values/costs, which are statistically dependent. Two mechanisms are considered. The buyer's bid double auction collects bids and asks from traders and determines the allocation by selecting a...

This paper develops a payoff equivalence theorem for mechanisms with ambiguity averse participants with preferences of the Maxmin Expected Utility (MEU) form (Gilboa and Schmeidler, 1989). We use our payoff equivalence result to explicitly characterize the revenue maximizing private value...

The rational expectations equilibrium (REE), as introduced in Radner (1979) in a general equilibrium setting à la Arrow–Debreu–McKenzie, often fails to have desirable properties such as universal existence, incentive compatibility and efficiency. We resolve those problems by providing a new...

We study the question of which social choice functions from an abstract type space to a set of outcomes are truthful, i.e., implementable by truthful mechanisms, when utilities are quasi-linear. For convex domains, our main theorem characterizes truthful social choice functions as those...

A buyer procures a network to span a given set of nodes; each seller bids to supply certain edges, then the buyer purchases a minimal cost spanning tree. An efficient tree is constructed in any equilibrium of the Bertrand game.