William Vickrey's predicted equivalences between first-price sealed-bid and Dutch auctions, and between second-price sealed-bid and English auctions, are tested using field experiments that auctioned off collectible trading cards over the Internet. The results indicate that the Dutch auction...

The authors model entry incentives in auctions with risk-neutral bidders and characterize a symmetric equilibrium in which the number of entrants is stochastic. The presence of too many potential bidders raises coordination costs that detract from welfare. The authors show that the seller and...