On Optimal Reservation Prices in Auctions

The theory of auction design examines how various factors affect the outcome of an auction. Most of the existing literature focuses on how varying the amount of information available to each bidder affects the bid-taker's expected revenue when all other factors remain constant. This paper studies how the bid-taker's expected revenue varies with changes in the auction format when such changes affect the number of bidders, and, in turn, the bidders' maximum value for the object being sold. Specifically, we examine how varying the reservation price or screening level affects the bid-taker's expected revenue though its effect on the number of bidders. For two simple examples, the losses associated with a reduced number of bidders outweighs any benefits that nontrivial reservation prices might have had in models with an exogonously set number of bidders.