Optimal two-object auctions with synergies

We design the revenue-maximizing auction for two objects when each buyer has bi-dimensional private information and a superadditive utility function (i.e., a synergy is generated if a buyer wins both goods). In this setting the seller is likely to allocate the objects inefficiently with respect to an environment with no synergies (see Armstrong, RES (2000)). In particular, the objects may be bundled too rarely or a buyer may win the bundle even though her valuations for the goods are weakly dominated by the values of another buyer.Received: 29 October 2001, Accepted: 29 October 2002, JEL Classification: D44, D82This paper has been written while the author was a member of the Dipartimento di Statistica e Matematica Applicata alle Scienze Umane "Diego De Castro", Universitá degli Studi di Torino, Italy. Valuable comments and suggestions were provided by Antonio Cabrales, Massimo Marinacci, three anonymous referees and, especially, by Mark Armstrong. The usual disclaimer applies.     

A green winner's curse? Investor behavior in the market for eco-certified office buildings

This paper contributes to the growing literature on the economics of green buildings: by merging auction theory and hedonic regression analysis we investigate the relationship between market concentration and price premiums in the American market for eco-certified real estate assets. Auction theory is used to model price formation where eco-investors may differ in their valuation of assets. Controlling for a large number of features, the empirical results provide evidence of a significant and positive relationship between investors’ eco-certified market share and prices of eco-certified space. Contributing to the recent debate over the nature of the green premium, we find that eco-investors are creating clientele effects and that they may be subject to a green winner's curse.     

A stochastic programming winner determination model for truckload procurement under shipment uncertainty

We propose a two-stage stochastic integer programming model for the winner determination problem (WDP) in combinatorial auctions to hedge the shipper’s risk under shipment uncertainty. The shipper allows bids on combinations of lanes and solves the WDP to determine which carriers are to be awarded lanes. In addition, many other important comprehensive business side constraints are included in the model. We demonstrate the value of the stochastic solution over one obtained by a deterministic model based on using average shipment volumes. Computational results are given that indicate that moderately sized realistic instances can be solved by commercial branch and bound solvers in reasonable time.     

A conceptual model of motivations for consumer resale on C2C websites

More consumers nowadays are acting the role of reseller by taking advantage of online consumer-to-consumer (C2C) auction sites. Such auctions may involve new behaviours created by the new technology. Yet the amateur consumer seller, a key player in C2C online auctions, has rarely been the focus of research; scholars know little about online reselling behaviour. Using a literature review, from participant observation and in-depth interviews with 48 Taiwanese consumers involved in 250 online resale transactions, 4 intrinsic motivations of online resale behaviour are identified. A conceptual model of consumer resale motivations is presented and corresponding research propositions are developed based on the existing literature and the preliminary findings of this exploratory empirical study. Finally, conclusions, managerial implications and outline directions for further research are discussed.     

Ascending price Vickrey auctions

We show that an ascending price auction for multiple units of a homogeneous object proposed by Ausubel (i) raises prices for packages until they reach those nonlinear and non-anonymous market clearing prices at which bidders get their marginal products and (ii) the auction is a primal–dual algorithm applied to an appropriate linear programming formulation in which the dual solution yields those same market clearing prices. We emphasize the similarities with efficient incentive compatible ascending price auctions to implement Vickrey payments when there is a single object or when objects are heterogeneous but each buyer does not desire more than one unit. A potential benefit of these common threads is that it helps to establish the principles upon which Vickrey payments may be implemented through decentralized, incentive compatible procedures.     

Going, Going, Gone! A Swift Tour of Auction Theory and its Applications

This paper provides a swift tour of auction theory and its applications. Among the questions it considers are: How much do bidders bid in commonly studied single-object auctions? How efficient are these auctions? How much revenue do they generate? Which single-object auction maximizes the seller’s expected revenue? What is the best way to auction incentive contracts? And, how efficient and complex are multi-object auctions?     

Budget-constrained sequential auctions with incomplete information

I study a budget-constrained, private-valuation, sealed-bid sequential auction with two incompletely-informed, risk-neutral bidders in which the valuations and income may be non-monotonic functions of a bidder's type. Multiple equilibrium symmetric bidding functions may exist that differ in allocation, efficiency and revenue. The sequence of sale affects the competition for a good and therefore also affects revenue and the prices of each good in a systematic way that depends on the relationship among the valuations and incomes of bidders. The sequence of sale may affect prices and revenue even when the number of bidders is large relative to the number of goods. If a particular good, say α, is allocated to a strong bidder independent of the sequence of sale, then auction revenue and the price of good α are higher when good α is sold first.     

Simple Reputation Systems*

We develop a model of simple “reputation systems” that monitor and publish information about the behavior of sellers in a search market with asymmetric information. The reputations created influence the equilibrium search patterns of buyers and thus provide for market‐based “punishment” of bad behavior. We show that a reputation system that rewards honesty can enhance welfare by allowing good sellers to truthfully signal their type. However, the same system can be prone to strategic manipulation by sellers who always have low‐quality products. In that case, we show that an alternative system which assigns reputations based on product quality rather than honesty can be superior.     

Auctions with options to re-auction

A seller has one unit to sell using an English auction mechanism similar to internet auction markets, such as eBay. Bidders appear according to a random arrival process. The seller chooses a reserve price and duration for each auction. If the reserve is not met, the seller passes in the object and conducts another auction with a new, randomly chosen, set of bidders. We distinguish reserves that embody an institutional commitment not to sell below that price, from those that do not. In each case, we find the optimal reserve price and the optimal auction duration. Without price commitment, the equilibrium reserve is too low for allocative efficiency, whereas the optimal reserve with commitment is shown to be too high when the distribution of bidder valuations exhibits an increasing hazard rate. It might even be socially preferable to allow reserve price commitments. With respect to duration, a version of the Diamond paradox afflicts sellers who cannot commit to price; auctions facilitate valuable duration commitments that increase buyer competition and raise expected revenue. With commitment, price posting (equivalent to a zero-length auction) is the dominant selling mechanism.     

Auctions with asymmetric common-values: The first-price format

We study the performance of the first-price format in auctions with asymmetric common-values. We show that, contrary to the result for second-price auctions, a small advantage for one player translates only to small changes in bidders’ strategies, and the equilibrium remains close to the first-price equilibrium of the original game. We characterize the equilibrium bidding strategies and their behavior as the degree of asymmetry increases. Finally, we compare the revenues at the optimal auction, the first-price auction and the second-price auction.