ADVERSE SELECTION IN ELECTRONIC MARKETS: EVIDENCE FROM ONLINE STAMP AUCTIONS

We analyze adverse selection costs in online stamp auctions, based on a comparison of prices on eBay with those of matched stamps at a specialty stamps auction site in the U.S., Michael Rogers, Inc. (MR), which we know a priori has low quality uncertainty. We find that buyer prices are 10–15% lower on eBay as compared to MR, and the price difference, increases with the value of the stamps. Consistent with this adverse selection discount we find that the seller reputation mechanism on eBay has an economically modest, although statistically significant, effect on auction price and probability of sale.     

Auction Platform Design and the Linkage Principle

This paper examines an auction platform in which the monopoly platform maximizes profits by adjusting participation fees and choosing an auction format. The seller has private information on the quality of the good, and each participating buyer receives a private signal about his valuation of the good. The choice of auction format determines the allocation of trading surplus between the seller and buyers. This paper shows that when the seller's type is affiliated with the buyers' signals, the platform can charge higher participation fees on both sides by choosing a first‐price or descending auction than a second‐price or ascending auction.     

Optimal reserve prices in sealed-bid auctions with reference effects

The reference effect and loss aversion are incorporated into the buyer’s utility in the symmetric independent private value models of sealed-bid auctions. The buyer’s equilibrium bidding strategy and the seller’s optimal reserve price are derived for the first-price and second-price sealed-bid auctions. In both auction mechanisms, the seller’s optimal reserve price and expected revenue are increasing in the reference point. We compare the seller’s expected revenues as well as the optimal reserve prices in the two auctions. The results show that the seller will set a higher optimal reserve price but obtain lower optimal expected revenue in the second-price auction compared to the first-price auction. Further, we extend the model to the gain-seeking case, and endogenize the reference point as the ex-ante expected price of the item in equilibrium. In contrast to the loss-averse case, the seller will set a lower optimal reserve price but obtain higher optimal expected revenue in the second-price auction compared to the first-price auction if the buyers are gain-seeking. With an endogenous reference point, similar results are obtained in terms of revenue comparison between the two auctions.     

First‐Price Sealed‐Bid Tender versus English Open Auction: Evidence from Land Auctions

This article compares whether the first‐price sealed‐bid tender or the ascending English open auction generates higher revenue for the seller. Using a unique set of data for land sales and accounting for the presence of an endogenous discrete mechanism choice variable, our results show that the first‐price sealed‐bid tender generates a lower land price, in the range of 1.2–9.6%, than the English open auction. Our results validate the theoretical prediction that open auctions result in higher prices because bidders can infer other bidders’ information by observing their bids in the common value auction paradigm.     

Warranty,Seller Reputation,and Buyer Experience: Evidence From EBAY Used Car Auctions

Using data from the eBay car auction market, we test several predictions regarding warranties, seller reputation and buyer experience in the determination of the final price. We find that the presence of a warranty generates a price premium, but that its magnitude decreases when the seller has a more established reputation. Compared to private sellers, professional dealers, who are ‘repeated‐game players’ in the market, benefit less from a warranty and its substitutability for seller reputation is relatively small. In addition, a buyer with greater experience tends to pay less for a warranty or for a professional dealership.     

Information disclosure in optimal auctions

This paper analyzes a situation in which the seller controls the accuracy of what potential buyers learn about their valuation of a good to be sold. This setting is related to many real situations such as home sales, antique auctions, and digital platforms such as Google and Facebook selling online advertising slots. Two important questions arise: what is the optimal selling mechanism, and what is the optimal disclosure policy of the seller. Under the assumption of private values, a simple auction with a reserve price is the optimal mechanism. What we show is that the amount of (costly) information provided increases with the number of potential bidders when using the optimal mechanism and is greater than when the object is always sold. Because information changes the distribution of a bidder’s expected valuations, the optimal reserve price also changes, so that the number of bidders (indirectly) affects the reserve price. We show that as the number of bidders increases, the optimal reserve price becomes more restrictive.     

Market Mechanism Choice and Real Estate Disposition: Search Versus Auction

We propose a model of mechanism choice in the disposition of real estate assets where we consider two alternatives: a search market and an auction. Within the search framework, we derive an equilibrium whereby buyers incur search costs and sellers incur holding costs for the period during which the property is not sold. In the auction alternative, the seller joins an existing pool of sellers in undertaking a multiple–object auction and pays a commission upon sale. Buyers and sellers freely choose their mechanisms, which in equilibrium are optimal given each group's conjectures about the mechanism choice of their counterpart. In equilibrium, an agent cannot benefit from deviating from his choice and each agent's beliefs are consistent with the equilibrium outcome. It is shown that (a) buyers with high search costs will choose auctions because the auction payoff imposes an upper bound on buyers' gains from search, and (b) prices at auctions will be higher. Using vacant lot sales data and a method–of–moment estimator which accounts for the presence of an endogenous discrete mechanism choice variable, we estimated a hedonic regression to detect the price effect. It was determined that, on average, lots sold for $1.44 per square foot more in auctions than in the search market, as predicted by our model.     

A Dynamic Model of Auctions with Buy‐It‐Now: Theory and Evidence

In the ascending‐price auctions with Yahoo!‐type buy‐it‐now (BIN), we characterize and derive the closed‐form solution for the optimal bidding strategy of the bidders and the optimal BIN price of the seller when they are both risk‐averse. The seller is shown to be strictly better off with the BIN option, while the bidders are better off only when their valuation is high enough. The theory also implies that the expected transaction price is higher in an auction with an optimal BIN price than one without a BIN option. This prediction is confirmed by our data collected from Taiwan's Yahoo! auctions.     

Secret reserve prices in first-price auctions

This article offers a theoretical explanation for the use of secret reserve prices in auctions. I study first-price auctions with and without secret reserve price in an independent private values environment with risk-neutral buyers and a seller who cares at least minimally about risk. The seller can fix the auction rules either before or after she learns her reservation value. Fixing the rules early and keeping the right to set a secret reserve price can be strictly optimal. Moreover, I describe the relation of using a secret reserve price to phantom bidding and non-commitment to sell.     

PENNIES FROM EBAY: THE DETERMINANTS OF PRICE IN ONLINE AUCTIONS*

This paper presents an exploratory analysis of the determinants of prices in online auctions for collectible United States one‐cent coins at the eBay web site. Starting with an initial data set of 20,000 auctions, we perform regression analysis on a restricted sample of 461 coins for which we obtained estimates of book value. We have three major findings. First, a seller's feedback ratings, reported by other eBay users, have a measurable effect on her auction prices. Negative feedback ratings have a much greater effect than positive feedback ratings do. Second, minimum bids and reserve prices have positive effects on the final auction price. In particular, minimum bids appear only to have a significant effect when they are binding on a single bidder, as predicted by theory. Third, when a seller chooses to have her auction last for a longer period of days, this significantly increases the auction price on average.     

Role of resource gap and value appropriation: effect of reputation gap on price premium in online auctions

In this study, we draw on the resource‐based view of the firm and on value‐based models of strategy to examine when firms appropriate value from their superior resources. We argue for the need to take into account the role of the resource gap between competitors rather than the absolute resource stock of the focal firm when examining the resource‐performance relationship. In particular, we investigate whether the ability of a reputable seller to command a price premium is influenced by the reputation gap (i.e., the reputation differences between the focal seller and its closest competitor standardized by the reputation stock of both sellers). We test our hypotheses on 72 matched pairs of online transactions screened from more than 2,000 auctions of new mobile phones on the Polish Internet auction site Allegro. We find that the ability of a reputable seller to command a price premium (1) increases with the size of the reputation gap between the focal seller and its matched competitor, and (2) becomes increasingly smaller for each additional unit of the seller reputation gap. Copyright © 2010 John Wiley & Sons, Ltd.     

Assessing the Performance of Real Estate Auctions

This article investigates the performance of real estate auctions relative to negotiated sales. It uses a repeat-sales methodology to control for unobserved differences in the quality of auction properties. Properties auctioned in Los Angeles during the 1980s boom sold at an estimated discount of 0%–9%, while sales in Dallas following the oil bust obtained discounts of 9%–21%. This evidence is consistent with the theoretical prediction that the auction discount increases in downturns when a seller trades-off a longer expected selling time in a search market against an immediate auction sale. The study finds no evidence of the declining price anomaly.     

Equilibrium price dispersion with heterogeneous searchers

Firms simultaneously set prices in a homogeneous-product market where uninformed consumers search for price information. Some uninformed consumers are “local” searchers who visit only one seller, whereas others search sequentially with an optimal reservation price. Equilibrium prices may follow a mixture distribution, with clusters of high and low prices separated by a zero-density gap. When the (exogenous) reservation price of local searchers depart from that of the optimizing sequential searchers by a relatively small amount, the presence of local searchers either has no effect on market outcomes or benefits all consumers. A reduction in search cost sometimes leads to higher equilibrium prices.     

Penny auctions

This paper studies penny auctions, a novel auction format in which every bid increases the price by a small amount, but placing a bid is costly. Outcomes of real-life penny auctions are often surprising. Even when selling cash, the seller may obtain revenue that is much higher or lower than its nominal value, and losers in an auction sometimes pay much more than the winner. This paper characterizes all symmetric Markov-perfect equilibria of penny auctions and studies penny auctions’ properties. The results show that a high variance of outcomes is a natural property of the penny auction format and high revenues are inconsistent with rational risk-neutral participants.     

Price Strategies for Idiosyncratic Goods—The Case of Housing

We determine the mechanism that a rational, profit-maximizing seller would use to revise his reservation price for a heterogeneous or infrequently exchanged good. For instance, while one dimension of a home's quality may be easily determined in competitive markets (e.g., the valuation of floor size, location, etc.), other dimensions of quality may be idiosyncratic (unit specific) and unobservable by the seller (e.g., aesthetics of the home). Here, a seller of a new or infrequently exchanged housing unit may use sales success information to revise his expectation of the unit's market-determined value and hence revise his reservation price. The rational seller will, upon arrival of the first buyer inspecting the unit, determine a sequence of reservation prices for this and expected subsequent buyers. This price sequence falls for subsequent buyers and starts from a lower initial price if the first buyer arrives later than expected. Through this mechanism, we offer an explanation for price dispersion and vacancy durations in housing markets. While we explicitly model the real estate market here, this price revision mechanism is also applicable to rental markets, labor markets, used car markets, and other markets characterized by heterogeneity and infrequent sales.     

Fighting collusion in auctions: An experimental investigation

The danger of collusion presents a serious challenge for auctioneers. In this paper, we compare the collusive properties of two standard auctions, the English auction and the first-price sealed-bid auction, and a lesser-known format, the Amsterdam (second-price) auction. In the Amsterdam auction, the highest losing bidder earns a premium for stirring up the price. We study two settings: in one, all bidders can collude, and in another, only a subset is eligible. The experiments show that the Amsterdam auction triggers less collusion than the standard auctions. We compare experimental results to theoretical predictions, and provide an explanation where they differ.     

Effects of seller’s information disclosure in equity auctions requiring post-auction investment

We consider a moral hazard issue inherent in the equity auctions of assets such as oil and gas leases and corporate takeovers. After the auction, the winning bidder decides whether to make follow-up investments in the acquired asset and makes the equity payment out of the revenue from it according to the auction outcome. Before the auction, the seller holds private information about the possible returns on that investment and must decide whether to disclose it. Larger equity payments undermine incentives to invest, reducing the impact of information revealed by the seller on expected values of the asset to a winning bidder. Thus, information disclosure makes bids less aggressive in expectation. Expected seller revenues may be higher when she does not disclose her private information than when she commits to publicly announcing it regardless of whether it is good or bad.     

Is the ‘Linkage Principle’ Valid? Evidence from the Field

We present field evidence concerning experienced bidders that supports the linkage principle—specifically, the prediction that in affiliated‐values auction environments the expected revenues generated at open‐outcry, ascending‐bid auctions are higher than those under auction formats that reveal less information to participants. Using field data from a large seller of automobiles who experimented with different selling formats, we have found that average revenues were significantly higher under an English auction than under a dynamic Internet auction format that revealed less information to bidders.     

How Do Land Auction Formats Influence the Market Structure and Aggregate Surplus of Real Estate Development?

This article proposes a duopoly dynamic game theoretic model to investigate the market structure and aggregate surplus of real estate development when land is sold in a sealed‐bid first price auction vis‐à‐vis an open English auction. It relaxes the assumption of symmetric bidders. The land values have common value and private value components. We find that the sealed‐bid first price auction introduces competition in the real estate development market. The open English auction leads a monopoly market. State agencies are recommended to increase the aggregate surplus of real estate development by publishing past bidding information under the sealed‐bid first price auction and reducing information asymmetry between bidders.     

Auction hosting site pricing and market equilibrium with endogenous bidder and seller participation

This paper characterizes the payoffs and pricing policies of auction hosting sites when both the bidders’ and the sellers’ participation is endogenous. Sellers have heterogeneous opportunity costs and make a listing decision depending on the listing fee and the expected revenue from the sale. On the other side of the market, factors such as facility in navigating an interface layout and prior bidding experience result in bidder heterogeneity with respect to participation costs. Bidders participate if their ex ante expected payoff from searching the site exceeds their participation costs. The auction site earns revenue by setting positive listing fees, trading off the increased revenue per seller resulting from a higher fee with the revenue reduction from the loss of sellers. Though this appears to be a classic monopoly problem, there are important differences. The reduction in the number of sellers participating in a site has feedback effects, as it affects the number of bidders who choose to visit that site, which in turn again affects the attractiveness of the site to sellers, and thus further reduces seller participation. In this environment the monopolist’s ability to extract rents is severely limited, even if one considers rent extraction from the seller side of the market only. It is demonstrated that the inverse demand curve is flatter than the demand curve obtained from the (inverse) distribution of seller costs. Moreover, the inverse demand curve has at least one and possibly multiple flat segments, leading to discontinuities in the profit function. Thus, small changes in the environment can lead to large changes in the optimal fee and market participation.