We consider collective choice from two alternatives. Ex ante, each agent is uncertain about which alternative she prefers, and may be uncertain about the intensity of her preferences. An environment is given by a probability distribution over utility vectors that is symmetric across agents and...

The English auction is susceptible to tacit collusion when post-auction interbidderresale is allowed. We show this by constructing equilibria where, withpositive probability, one bidder wins the auction without any competition anddivides the spoils by optimally reselling the good to the other...

We consider 2-bidder first-price auctions where one bidder's value is commonly known. Such auctions induce an ineffcient allocation. We show that a resale opportunity, where the auction winner can make a take-it-or-leave-it offer to the loser, increases (reduces) the ineffciency of the market...

In standard auctions with symmetric, independent private value bidders resale creates a role for a speculator - a bidder who is commonly known to have no use value for the good on sale. For second-price and English auctions the efficient value-bidding equilibrium coexists with a continuum of...

Zheng has recently proposed a seller-optimal auction for (asymmetric) independentprivate- value environments where inter-bidder resale is possible. Zheng's construction requires novel conditions on the bidders' value distribution profile. We clarify the restrictions implied by these conditions....

We consider the problem of mechanism design by a principal who has private information. We point out a simple condition under which the privacy of the principal's information is irrelevant in the sense that the mechanism implemented by the principal coincides with the mechanism that would be...

Majority rules are frequently used to decide whether or not a public good should be provided, but will typically fail to achieve an efficient provision. We provide a worst-case analysis of the majority rule with an optimally chosen majority threshold, assuming that voters have independent...

Zheng has proposed a seller-optimal auction for (asymmetric) independent-privatevalue environments where inter-bidder resale is possible. Zheng's construction requires novel conditions '€" Resale Monotonicity, Transitivity, and Invariance '€" on the bidders' value distribution profile. The...

We show that, in environments with independent private values and transferable utility, a privately informed principal can implement a contract that is ex-ante optimal for her. As an application, we consider a bilateral exchange environment (Myerson and Satterthwaite, 1983) in which the...

In standard auctions with symmetric, independent private value bidders resale creates a role for a speculator'€"a bidder who is commonly known to have no use value for the good on sale. For second-price and English auctions the efficient value-bidding equilibrium coexists with a continuum of...