Existence of optimal auctions in general environments

We provide a unified approach to the problem of existence of optimal auctions for a wide variety of auction environments. We accomplish this by first establishing a general existence result for a particular Stackelberg revelation game. By systematically specializing our revelation game to cover various types of auctions, we are able to deduce the existence of optimal Bayesian auction mechanisms for single and multiple unit auctions, as well as for contract auctions with moral hazard and adverse selection. In all cases, we allow for risk aversion and multidimensional, stochastically dependent types.     

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.     

Pseudocontinuous functions and existence of Nash equilibria

In topological spaces, we introduce a new class of functions (pseudocontinuous functions) and we present some characterizations and properties. In particular, we show that any preference relation endowed of utility functions is continuous if and only if any utility is pseudocontinuous. A maximum theorem is proved for such a class of functions and connections with similar results are investigated. Finally, the existence of Nash equilibria for games with pseudocontinuous payoffs is obtained.     

Characterization of bidding behavior in multi-unit auctions

This paper considers a very general class of single or multi-unit auctions of indivisible objects. The model allows for interdependent values, multidiminensional types and any attitude towards risk. Assuming only optimal behavior, we prove that each bid is chosen in order to equalize the marginal benefit to the marginal cost of bidding. This generalizes many existing results in the literature. We use this characterization to obtain sufficient conditions for truthful bidding, monotonic best reply strategies and identification results for multi-unit auctions.     

Defensive sniping and efficiency in simultaneous hard-close proxy auctions

A well-known myopic bidding strategy fails to support an equilibrium of simultaneous ascending proxy auctions for heterogeneous items when a hard-close rule is in place. This is because, in common with the single-auction case, last minute bidding (sniping) is a best response to naive behaviour. However, a modification to the myopic strategy in which all bidders submit an additional bid in the closing stages of the auction–a practice I call ‘defensive sniping’–is shown to yield an efficient, belief-free equilibrium of such environments. This equilibrium is essentially unique within the class of belief-free, efficient equilibria.     

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.     

Second‐Price Auctions with Different Participation Costs

This paper studies equilibria of second‐price auctions in independent private value environments with different participation costs. Two types of equilibria are identified: monotonic equilibria in which a bidder with a lower participation cost results in a lower cutoff for submitting a bid, and nonmonotonic equilibria in which a lower participation cost results in a higher cutoff. We show that there always exists a monotonic equilibrium, and further, that the monotonic equilibrium is unique for either concave distribution functions or strictly convex distribution functions with nonincreasing reverse hazard rates. There exist nonmonotonic equilibria when the distribution functions are strictly convex and the difference of the participation costs is sufficiently small. We also provide comparative static analysis and study the limiting properties of equilibria when the difference in bidders’ participation costs approaches zero.     

User acceptance of complex electronic market mechanisms: Role of information feedback

This paper broadens the scope of evaluating the design of economic mechanisms that is traditionally done solely from an economic perspective. We introduce and demonstrate the application of acceptability to evaluate complex economic mechanisms. In particular, we apply our approach to the evaluation of continuous combinatorial auctions, which represent a complex, sophisticated market mechanism that has not been generally available in the online marketplace but has the potential to enhance the economic efficiency of trade for assets with interdependent values. Such auctions are being increasingly used in industry, e.g., to procure logistical services. Intuitively, acceptance and usage of a complex mechanism can be fostered by a design that provides information and tools that meet the users’ task demands. Based on prior research and an analysis of the auction tasks, we discuss practical and innovative information feedback schemes for reducing the cognitive burden of formulating bids in combinatorial auctions. Then, we use constructs from the technology acceptance model (TAM) – which have been consistently shown to be key determinants of technology acceptance in the extant literature – to compare the acceptability of the mechanism under three different information regimes. In addition, we borrow constructs from marketing theory to assess the potential growth in adoption of the mechanism. We compare user perceptions of the three alternative designs in a laboratory experiment with over 130 subjects. Our study constitutes a complementary and novel approach in evaluating the design of complex economic mechanisms. Results indicate a higher adoption and usage potential of the mechanism with advanced information feedback, supporting the potential of combinatorial auctions as a user-acceptable market mechanism with appropriate feedback.     

Financial contracts as coordination device

We study the use of financial contracts as bid‐coordinating device in multi‐unit uniform price auctions. Coordination is required whenever firms face a volunteer's dilemma in pricing strategies: one firm (the “volunteer") is needed to increase the market clearing price. Volunteering, however, is costly, as inframarginal suppliers sell their entire capacity whereas the volunteer only sells residual demand. We identify conditions under which signing financial contracts solves this dilemma. We test our framework exploiting data on contract positions by large producers in the New York power market. Using a Monte Carlo simulation, we show that the contracting strategy is payoff dominant and provide estimates of the benefits of such strategy.     

Your failure is my opportunity—Effects of elimination in contests

In this paper, we consider a sequence of multi-prize all-pay auctions, where low-performing players are eliminated along the way. We provide sufficient conditions such that equilibrium behavior is unaffected by the prospects of winning prizes in later rounds. When these conditions are not met, we identify a novel externality effect and derive equilibria in a model with two rounds. We compare our results to knockout tournaments in which players are partitioned into subcontests in each round.     

Non-existence of equilibrium in Vickrey, second-price, and English auctions

A simple example shows that equilibria can fail to exist in second price (Vickrey) and English auctions when there are both common and private components to bidders’ valuations and private information is held on both dimensions. The example shows that equilibrium only exists in the extremes of pure private and pure common values, and that existence in standard models is not robust to a slight perturbation.     

Retaliatory Equilibria in a Japanese Ascending Auction for Multiple Objects

We construct a family of retaliatory equilibria for the Japanese ascending auction for multiple objects and show that, while it is immune to many of the tacitly collusive equilibria studied in the literature, it is not entirely immune when some bidders are commonly known to be interested in a specific object.     

在线拍卖中的代理研究综述

在线拍卖站点的不断增加给在线竞买人提出了具大的挑战,竞买人需要从大量的拍卖站点中选择一个恰当的拍卖站点,以保证在满足他们偏好的前提下得到他们希望的物品。不同的拍卖站点采用的拍卖方式和竞价策略是不同的,因此,不同的拍卖站点其竞价代理的设计策略也不同。本文主要对目前在线拍卖代理研究进行综述。     

The Auction Price of Apartments in Moscow: Hedonic Estimation in Disequilibrium1

The purpose of this paper is to see how economic factors determine prices in the previously communist countries undergoing privatization. This does not concern the auctions of big state enterprises where the prices are found to be rigged. In this paper we estimate hedonic price functions based on a unique data set on auction prices of apartments in Moscow. We collected the data ourselves by attending the auctions and gathered data on the characteristics. We estimated the hedonic equations using a disequilibrium approach because no equilibrium prices were observed for large number of apartments that were withdrawn from the auction. We found that, as the privatization of residential housing was carried out, the hedonic price equations fit the data remarkably well.     

CROSS‐SECTIONAL DEPENDENCE AND SPILLOVERS IN SPACE AND TIME: WHERE SPATIAL ECONOMETRICS AND GLOBAL VAR MODELS MEET

To enhance the measurement of economic and financial spillovers, we bring together the spatial and global vector autoregressive (GVAR) classes of econometric models by providing a detailed methodological review where they meet in terms of structure, interpretation, and estimation. We discuss the structure of connectivity (weight) matrices used by these models and its implications for estimation. To anchor our work within the dynamic literature on spillovers, we define a general yet measurable concept of spillovers. We formalize it analytically through the indirect effects used in the spatial literature and impulse responses used in the GVAR literature. Finally, we propose a practical step‐by‐step approach for applied researchers who need to account for the existence and strength of cross‐sectional dependence in the data. This approach aims to support the selection of the appropriate modeling and estimation method and of choices that represent empirical spillovers in a clear and interpretable form.     

Ranking reversals in asymmetric auctions

This paper compares the first-price auction and the second-price auction with several asymmetric bidders who are either weak or strong. The ranking of these auctions in terms of profit may flip as the exogenous reserve price or the number of weak or strong bidders change. Similarly, with endogenous reserve prices the ranking may depend on the seller’s own-use valuation. In other words, the ranking may be fragile to changes along these dimensions. Existing models rule out such ranking reversals by imposing substantial structure on type distributions. The current paper relies on simple mechanism design arguments that require less structure.     

Synergies and price trends in sequential auctions

In this paper we consider sequential second-price auctions where an individual's value for a bundle of objects is either greater than the sum of the values for the objects separately (positive synergy) or less than the sum (negative synergy). We show that the existence of positive synergies implies declining expected prices. When synergies are negative, expected prices are increasing. There are several corollaries. First, the seller is indifferent between selling the objects simultaneously as a bundle or sequentially when synergies are positive. Second, when synergies are negative, the expected revenue generated by the simultaneous auction can be larger or smaller than the expected revenue generated by the sequential auction. In addition, in the presence of positive synergies, an option to buy the additional object at the price of the first object is never exercised in the symmetric equilibrium and the seller's revenue is unchanged. Under negative synergies, in contrast, if there is an equilibrium where the option is never exercised, then equilibrium prices may either increase or decrease and, therefore, the net effect on the seller's revenue of the introduction of an option is ambiguous. Finally, we examine a special case with asymmetric players who have distinct synergies. In this example, even if one player has positive synergies and the other has negative synergies, it is still possible for expected prices to decline.Received: 12 December 2000, Accepted: 1 May 2002, JEL Classification: D44Flavio Menezes acknowledges the financial support from ARC (Grant A000000055) and CNPq. Monteiro acknowledges the financial support from CNPq and the hospitality of CERSEM where part of this paper has been written. We thank Richard Engelbrecht-Wiggans, Peter Sørensen and two anonymous referees for useful comments.     

Optimal fees in internet auctions

An auction house runs a second-price auction with a possibility of resale through re-auctions. It collects listing and closing fees from the seller. We find the fees which maximize the revenue of the auction house. In particular, we show that the optimal listing fee is zero. Our findings are consistent with the policies of eBay, Amazon, Yahoo, and other Internet auctions.      

The use of bundling in B2B online reverse auctions

In industrial purchasing a request for quotation (RFQ) can consist of a single item, but is most often composed of two or more products and/or services bundled together. While such bundles are used in offline purchase negotiations, their criticality is heightened in online auctions due to their usual short duration and constrained bidding environment. Despite this importance, little systematic discussion or evaluation has taken place concerning bundling practice, especially as it relates to the individual items included in the bundle, the overall bundle composition, and the resulting supply base and ultimate bundle performance. This study investigates these issues by developing a conceptual model and testing it with a large-scale survey completed by purchasing professionals practicing bundling in B2B online auctions. Results indicate that crafting a more homogeneous bundle is most important in achieving a successful outcome. Furthermore, more complex or difficult-to-specify items do not impact perceived bundle performance, but do influence the supply base that is willing and able to bid on the business.