53. Auction Design by an Informed Seller: The Optimality of Reserve Price Signaling
Xin Zhao, University of Technology Sydney
Date of publication: 6th October 2018
Working paper number: 53
This paper studies mechanism design by a seller privately informed of the quality of an indivisible object. The privacy of the seller’s information matters for mechanism design: selecting a mechanism that maximizes the seller’s profit when her information is public is not incentive compatible for the seller when her information is private, as a lower-quality seller has an incentive to mimic a higher-quality seller. I show that reserve prices are the least costly device to separate higher-quality sellers from lower-quality ones. In equilibria that maximize the expected profit of every type of the seller among all separating equilibria, the lowest-quality seller adopts her public-information optimal mechanism, and each higher-quality seller adopts a mechanism that differs from her public-information optimal mechanism only in that the reserve prices are higher.