Implementing Efficient Multi-Object Auction Institutions:

Abstract We study three alternative implementations of the Vickrey (1961) multi-unit demand auction: Vickrey’s original static sealed-bid auction and two dynamic alternatives, with and without public dropout information reported during the auction (Ausubel, 2004). Although implemented by a weaker solution concept, behavior in the dynamic Vickrey auction with the public dropout information comes significantly closer to the theoretical prediction of sincere bidding, bidding one’s valuations, than either the static Vickrey auction or the dynamic auction without dropout information. This suggests a possible tradeoff between the simplicity and transparency of a mechanism and the strength of its solution concept when agents are still learning and/or when players are not fully rational. Drawing on results from related single unit and multi-unit demand auctions, and the results of a new single unit demand auction experiment, we provide important insights into the behavioral mechanism underlying the superior performance of the Ausubel auction.