On the lowest-winning-bid and the highest-losing-bid auctions

Theoretical models of multi-unit, uniform-price auctions assume that the price is given by the highest losing bid. In practice, however, the price is usually given by the lowest winning bid. We derive the equilibrium bidding function of the lowest-winning-bid auction when there are k objects for sale and n bidders with unit demand, and prove that it converges to the bidding function of the highest-losing-bid auction if and only if the number of losers n−k gets large. When the number of losers grows large, the bidding functions converge at a linear rate and the prices in the two auctions converge in probability to the expected value of an object to the marginal winner.     

Competitive bidding and proprietary information

We consider the sale of an object by sealed-bid auction, when one bidder has private information and the others have access only to public information. The equilibria of the bidding game are determined, and it is shown that at equilibrium the informed bidder's distribution of bids is the same as the distribution of the maximum of the others' bids. The expected profit of the informed bidder is generally positive, while the other bidders have zero expected profits. The equilibrium bid distributions and the bidders' expected profits are shown to vary continuously in the parameters of the bidding game.     

He who must not be named

Landsberger et al. have studied a sealed bid first price auction with two players in which the ranking of the valuations is known. They argue that such a situation can arise in a sequential auction where only the name of the winner is revealed. In this paper we consider sequential auctions where two identical goods are sold sequentially to N players who are interested in both objects. In sealed bid auctions, no information is a priori revealed by the mechanism, but the seller can in principle reveal whatever he wants. We restrict our attention to the case where only the name of the winner is revealed to be in the context of Landsberger et al. for the second auction. The aim of the paper is to compare such a sequential auction with a simultaneous auction where both goods are sold as a bundle or equivalently with a sequential auction where no information is revealed. We first show that there exists an equilibrium of the sequential game in pure and monotone strategies. Then, the comparison of the seller's expected revenue in the two cases allows us to conclude that contrary to Landsberger et al.'s predictions, the seller can not use the information to increase his revenue. This result is obtained using simulations for a large class of distribution functions. The seller must not reveal the name of the winner between the two auctions and instead sell both goods using a simultaneous auction.Received: 31 July 2001, Accepted: 5 February 2003, JEL Classification: B44I wish to thank Laurent Linnemer, Thomas Ricke, Michael Visser and Shmuel Zamir for helpful comments and suggestions. I am very grateful to the referees and the associated editors in charge of my paper.     

The public release of information in first-price sealed-bid auctions

We determine the conditions under which the seller in a first-price sealed-bid auction has an incentive to reveal his private information about the mean of bidders’ valuations in order to increase his expected revenue. With risk-neutral bidders, we show that the seller’s expected revenue is higher when information is revealed. However, when bidders are risk-averse, this result does not necessarily hold; it depends on the bidders’ risk-aversion level and on the number of bidders.     

Optimal disclosure of costly information packages in auctions

In an independent, private values, second-price auction with entry fees we discuss the way in which a seller should optimally spread costly information among the bidders. We find that marginal gross revenues do not generally behave monotonically in total information release. In the two bidder case, essentially, any asymmetric allocation of information dominates the symmetric information allocation. Even the bidder who gets less information is willing to pay a higher entry fee for asymmetric information allocations than for the symmetric one. His entry fee coincides with that of the better informed bidder. Losses from allocating an amount of information non-optimally can be substantial.     

Optimal auctions and information disclosure

We characterise properties of optimal auctions if the seller may disclose information about the quality of the object for sale. We show that the seller maximizes his expected revenue by revelation of all information to all bidders and implementing a second price auction with appropriate reservation price.     

Bids as a Vehicle of (Mis)Information: Collusion in English Auctions with Affiliated Values

In an English auction, a bidder’s strategy depends on the prices at which his competitors drop out, because these convey information on the value of the object on sale. A ring of colluding bidders can strategically manipulate the information transmitted through its members’ bids, in order to mislead other bidders into bidding less aggressively and thus allow a designated bidder to bid more aggressively. Collusion increases the probability that the ring wins the auction and reduces the price it pays. The presence of a ring harms other bidders (as well as the seller) and reduces efficiency.     

Auctions with endogenous participation

We study endogenous-participation auctions where bidders only know the number of potential participants. After seeing their values for the object, potential participants decide whether or not to enter the auction. They may not want to enter the auction since they have to pay participation costs. We characterize equilibrium bidding strategies and entry decisions for both first- and second-price sealed-bid auctions when participation is endogenous. We show that there is a pure strategy entry equilibrium where only bidders with values greater than a certain cut-off point actually bid. In this context, both types of auctions generate the same expected revenue. We also show that, contrary to the predictions of the fixed number of bidders literature, the seller's expected revenue may decrease when the number of potential participants increases. In addition, we show that it is optimal for the seller to charge an entry fee, which contrasts with results from the existing literature on auctions with entry. As in the fixed-n literature, we show that first-price auctions generate more expected revenue than second-price auctions when buyers are risk-averse. Finally, we characterize the optimal auction – the auction that maximizes the seller's expected revenue – by using a direct revelation mechanism. The optimal auction involves a reserve price larger than the optimal reserve price in the fixed-n literature. The winner's payment is the second highest bid less the participation cost and losers receive a subsidy equal to the participation cost. Received: 17 August 1998 / 21 September 1999     

Information acquisition and/or bid preparation: A structural analysis of entry and bidding in timber sale auctions

Recently, several auction models with entry have been proposed: in one model ( and ), bidders are assumed to draw their private values after they decide to enter. In another model ( and ), bidders are assumed to learn their values before their entry decisions are made. The entry cost in the latter model can be interpreted as bid preparation cost, while the entry cost in the former model consists of both costs from information acquisition and bid preparation. Moreover, these two models have different implications for important policies, e.g., the optimal reserve price. In this paper we provide a unified structural framework where the two models can be estimated and distinguished using the Bayesian method. We apply our method to analyze Michigan timber sale auctions.     

On the existence of an increasing symmetric equilibrium in (k + 1)-st price common value auctions

In a classical result, Milgrom (1981a) established that the Monotone Likelihood Ratio Property (MLRP) is a sufficient condition for the existence of an increasing symmetric equilibrium in (k + 1)-st price common value auctions. We show: (1) If MLRP is violated, then for any number of bidders and objects there exists a distribution of the common value such that no increasing symmetric equilibrium exists; (2) If MLRP is violated, then for any distribution of the common value there exist infinitely many pairs of the number of bidders and the number of objects such that an increasing symmetric equilibrium does not exist; (3) There are examples where an increasing symmetric equilibrium exists even when the signal distribution violates MLRP.     

Almost Common Value Auctions: An Experiment

In almost common value auctions one bidder has a higher (private) value for the item than the other bidders. Theory predicts that even a small private value advantage can have an explosive effect in English auctions, with advantaged bidders always winning and sharp decreases in revenue. These predictions fail to materialize for experienced bidders who have learned to avoid the worst effects of the winner's curse. Bidding is better characterized as proportional, with advantaged bidders tending to bid as in a pure common value auction after adding their private value advantage to their estimated value of the item.     

Insider trading,overconfidence, and private information flow

In this study, we investigate a dynamic model wherein an overconfident and a risk-neutral informed trader optimally exploit their long-lived private information regarding the value of an asset. We find that when the degree of overconfidence becomes larger, or the intensity of private information flow becomes larger relative to the initial private signal, the market becomes more stable. Additionally, we find that the greater the intensity of private information flow relative to the initial private signal, the more evident the patient transaction and the slower the information is incorporated in the price.     

Who else is bidding? The Pareto optimality of disclosing bidder identities

This paper examines whether the seller of an object should reveal the identities of the participating bidders before bids become due. It is shown that when bidders experience identity dependent externalities and auction participation is exogenous, then for a large class of standard auction mechanisms, a policy of revelation serves to realize a higher surplus because it improves the accuracy of each bidder's estimate of her ex-post willingness-to-pay, and therefore changes the auction allocation in a more ex-post efficient manner. Furthermore, it is shown that the policy of revelation increases both the expected seller revenues as well as ex-ante expected bidder payoffs. Received: 4 February 2000 / Accepted: 15 November 2000 An earlier version of this paper had the title 'Disclosure of Bidder Identities'. I thank an anonymous referee and an Associate Editor for suggestions that improved the paper. I also acknowledge comments made by participants of the Auctions session during the North American Winter Meetings of the Econometric Society 2001 held in New Orleans. I remain solely responsible for any errors.     

The generalized Stackelberg equilibrium of the all-pay auction with complete information

We characterize the equilibrium of the all-pay auction with general convex cost of effort and sequential effort choices. We consider a set of n players who are arbitrarily partitioned into a group of players who choose their efforts ‘early’ and a group of players who choose ‘late’. Only the player with the lowest cost of effort has a positive payoff in any equilibrium. This payoff depends on his own timing vis-a-vis the timing of others. We also show that the choice of timing can be endogenized, in which case the strongest player typically chooses ‘late’, whereas all other players are indifferent with respect to their choice of timing. In the most prominent equilibrium the player with the lowest cost of effort wins the auction at zero aggregate cost. We thank Dan Kovenock and Luis C. Corchón for discussion and helpful comments. The usual caveat applies. Wolfgang Leininger likes to express his gratitude to Wissenschaftszentrum Berlin (WZB) for its generous hospitality and financial support.     

On the strictly descending multi-unit auction

We analyze the bidding behavior in a strictly descending multi-unit auction where the price decreases continuously without going back to the initial start price once an object is sold. We prove that any equilibrium in the multi-unit descending auction is inefficient. We derive a symmetric equilibrium for general distribution functions as well as an arbitrary number of bidders and objects. Moreover, equilibrium bidding is characterized by a set of initial value problems. Our analysis thus generalizes previous results in the literature.     

Bundling and the Reduction of the Winner's Curse

The paper studies the effects of bundling on the bidding strategies and seller revenues in auctions when the bidders have common values for the objects. Bundling of objects before the auction reduces the problem of the winner's curse, and the bidders bid more aggressively. This does not mean that a bundled auction is always better for the seller's revenue. Indeed, there is another effect that makes the bundled auction preferable (from the seller's standpoint) if and only if the number of bidders is small. While this is the only effect present in an independent-private-values model, it does not vanish when bidders have pure common values for the objects. The paper concludes that a bundled auction is unambiguously better for the seller than separate auctions when the number of bidders is small.     

Optimal auctions for asymmetrically budget constrained bidders

We consider an environment with a single divisible good and two bidders. The valuations of the bidders are private information but one bidder has a commonly known budget constraint. For this environment we derive the revenue maximizing subsidy free dominant strategy incentive compatible auction.      

Pre-play communication in procurement auctions: Silence is not golden

I study the effect of cheap talk between bidders on the outcome of a first-price procurement auction in which participation is costly. Although no side payments or commitments are allowed, there exists a family of equilibria in which sellers use communication to collude on a subset of participants and/or reveal information about their cost. Cheap talk matters in the sense that it strictly enlarges the set of Nash equilibria (symmetric and asymmetric) and the set of public correlated equilibria of the game. I show that the buyer may benefit from cheap talk between sellers and that the surplus increases in the amount of information revealed in equilibrium under one fairly general condition. This is because when communication is cheap, sellers cannot directly collude on higher prices. Rather, communication leads to competition between fewer, but more aggressive bidders, which entails greater allocative efficiency and a decrease in the total wasteful entry cost.     

Equilibrium in incomplete markets: II : Generic existence in stochastic economies

We model multiperiod securities markets with differential information. A price system that admits no free lunches is related to martingales when agents have rational expectations. We introduce the concept of resolution time, and show that a better informed agent and a less informed agent must agree on the resolution times of commonly marketed events if they have rational expectations and if there are no free lunches. It then follows that if all elementary events are marketed for a less informed agent then any price system that admits no free lunches to a better informed agent must eliminate any private information asymmetry between the two. We provide an example of a dynamically fully revealing price system that is arbitrage free and yields elementarily complete markets.     

Anticipation of Auction Fever: Entry Decision,Reserve Price and the Choice of Auction Design

This paper analyzes the entry decision of rational bidders who expect to experience auction fever in English auctions. It shows that nonparticipation decision reduces seller's expected profit and this effect may outweigh the positive effect of the auction fever. We analyze the choice between English and second‐price sealed‐bid auctions and the optimal reserve price in English auctions. We show that it might be optimal for the seller to set a reserve price below her own valuation of the object. Finally, we show that the order in which bidders place their bids matters and the first bidder always has an advantage. Copyright © 2011 John Wiley & Sons, Ltd.