This paper considers procurement auctions with costly bidding when the auctioneer is unable to commit himself to restrict the number of bidders. The auctioneer can, however, offer a financial reward to be paid to every short-listed bidders as an indirect commitment device. Rewards for...

In mechanism design, Myerson regularity is often too weak for a quantitative analysis of performance. For instance, ratios between revenue and welfare, or sales probabilities may vanish at the boundary of Myerson regularity. This paper therefore explores the quantitative version of Myerson...