Dutch vs. first-price auctions with expectations-based loss-averse bidders

We study Dutch and first-price auctions with expectations-based loss-averse bidders and show that the strategic equivalence between these formats no longer holds. Intuitively, as the Dutch auction unfolds, a bidder becomes more optimistic about her chances of winning; this stronger “attachment” effect pushes her to bid more aggressively than in the first-price auction. Thus, Dutch auctions raise more revenue than first-price ones. Indeed, the Dutch auction raises the most revenue among standard auction formats. Our results imply that dynamic mechanisms that make bidders more optimistic raise more revenue, thereby rationalizing the use of descending-price mechanisms by sellers in the field.