and Okan Yilankaya. Equilibria in second price auctions with participation costs

We investigate equilibria of sealed-bid second price auctions with bidder participation costs in the independent private values environ-ment. We focus on equilibria in cuto ¤ strategies (participate and bid the valuation i ¤ it is greater than the cuto¤), since if a bidder \u85nds it optimal to participate, she cannot do better than bidding her valua-tion. When bidders are symmetric, concavity (strict convexity) of the cumulative distribution function from which the valuations are drawn is a su ¢ cient condition for uniqueness (multiplicity) within this class. We also study a special case with asymmetric bidders and show that concavity/convexity plays a similar role. Journal of Economic Litera