If bidders are uncertain whether the auctioneer sticks to the announced reserve, some bidders respond by not bidding, speculating that the auctioneer may revoke the reserve. However, the reserve inadvertently signals the auctioneer's type, which drives a unique separating and a multitude of...

This article studies the design of optimal mechanisms to regulate entry in natural oligopoly markets, assuming the regulator is unable to control the behavior of firms once they are in the market. We adapt the Clark-Groves mechanism, characterize the optimal mechanism that maximizes the weighted...