procurement auction formats can take advantage of bidders' willingness-to-pay-willingness-to-accept disparity. In a laboratory … experiment, we compare four different second-price auction formats for procuring a good. The four formats are a sealed …-bid auction and three di erent descending-clock auctions. We assume that a bidder's willingness-to-accept exceeds his willingness …

-price dimensions after the auction. Both auctions theoretically implement the surplus maximizing mechanism. Our experiment confirms …. We do so in procurement settings where the buyer can give the winning bidder incentives to exert effort on non …