A Network Bidder Behavior Model in Online Auctions: A Case of Fine Art Auctions

The marketing literature provides a solid understanding of auctions regarding final sales prices and many aspects of the processes that unfold to result in those outcomes. This research complements those perspectives by first presenting a new bidder behavior model that shows the role of emergent network ties among bidders on the auction outcome. Dyadic ties are identified as the bid and counter-bid patterns of interactions between bidders that unfold throughout the duration of an auction. These structures are modeled using network analyses, which enables: (1) a richer understanding of detailed auction processes, both within auctions and across auctions of multiple lots, (2) a mapping of the processes to the forecast of prices and the trajectory toward final sales prices, (3) the clear and early identification of key bidders who are influential to the bidding action and who impact final auction sales prices, and (4) the results clearly show that the network exchange patterns are significant and contribute to an understanding of auction processes and outcomes above and beyond simple economic predictors such as the number of bids or bidders or the bidders’ economic status. We conclude by providing some managerial implications for online auction houses and bidders.     

The influence of seller strategy on the winning price in online auctions: A moderated mediation model

This paper examines the impact of seller strategy on winning prices in online auctions. In our conceptual model, three strategic choices made by the seller - minimum opening price, auction length, and use of a hidden reserve price - are mediated by the number of bids placed during the auction and moderated by product type. Our tests analyze eBay auction data for four consumer products through two matched studies (two products per study). In particular, we compare products for which value is easily determined with those for which value is less clear. Overall, we find strong evidence of the effects of minimum opening price and hidden reserve prices on final winning prices. The impact of auction length on winning price is less clear. In general, our tests support the idea that potential buyers rely more on signals such as opening price and reserve price for products for which reference prices are less available.     

Auction Fever! How Time Pressure and Social Competition Affect Bidders’ Arousal and Bids in Retail Auctions

Auction sites on the Internet frequently put bidders under time pressure or highlight the social competition that is inherent to auctions. Both aspects are believed to elicit an exciting shopping experience, which may culminate in auction fever. In two laboratory experiments, we investigate the process of auction fever in retail auctions and demonstrate when and how auction fever affects bidding behavior. In contrast to previous studies, we employ physiological measurements as an objective and continuous assessment of bidders’ arousal in addition to a subjective assessment of bidders’ emotions through psychometric scales. Moreover, we explicitly study the interaction of time pressure and social competition on arousal and bids. We find that bidders’ arousal is increased in high time pressure auctions and that this leads to higher bids in ascending auctions—but only when bidders compete with human opponents. Thus, social competition is the actual driver underlying the auction fever phenomenon. Furthermore, we show that the “joy of winning” is significantly stronger than the “frustration of losing” in ascending auctions. Finally, we discuss the implications of our findings for the design of retail auctions.     

IDENTIFYING THE LINDAHL EQUILIBRIUM WITHOUT TRANSFERS AS A SOCIAL OPTIMUM

The Lindahl equilibrium is an important solution concept in economies with externalities or public goods. In this paper, a ‘Negishi‐type’ theorem that connects the Lindahl equilibrium without transfers with the social optimum solution is proposed and proved. The theorem states that the solution of a social planner's problem with the social welfare weights proportional to the inverse of the private shadow prices of externalities in an auxiliary Nash equilibrium is the Lindahl equilibrium without transfers. To verify the theorem constructively, an algorithm for finding the Lindahl equilibrium is developed. Its efficacy is demonstrated through a numerical example.     

An Analysis of Design Problems in Combinatorial Procurement Auctions

Traditional auction mechanisms support price negotiations on a single item. The Internet allows for the exchange of much more complex offers in real-time. This is one of the reasons for much research on multidimensional auction mechanisms allowing negotiations on multiple items, multiple units, or multiple attributes of an item, as they can be regularly found in procurement. Combinatorial auctions, for example, enable suppliers to submit bids on bundles of items. A number of laboratory experiments has shown high allocative efficiency in markets with economies of scope. For suppliers it is easier to express cost savings due to bundling (e. g., decreased transportation or production costs). This can lead to significant savings in total cost of the procurement manager. Procurement negotiations exhibit a number of particularities:

(Un)expected Bidder Behavior in Spectrum Auctions: About Inconsistent Bidding and Its Impact on Efficiency in the Combinatorial Clock Auction

The combinatorial clock auction is a two-stage auction format, which has been used to sell spectrum licenses worldwide in the recent years. It draws on a number of elegant ideas inspired by economic theory. A revealed preference activity rule should provide incentives to bid straightforward, i.e., consistent with the bidders’ valuations on a payoff-maximizing package, in each round of the clock phase. A second-price rule should set incentives to bid truthfully in both phases. If bidders respond to these incentives and bid straightforward in the clock phase and truthful in the second sealed-bid stage, then the auction is fully efficient. Unfortunately, bidders might neither bid straightforward in the clock phase nor truthful on all packages in the second sealed-bid stage due to strategic reasons or practical limitations. We introduce metrics based on Afriat’s Efficiency Index to analyze straightforward bidding and report on empirical data from the lab and from the field in the British 4G auction in 2013 and the Canadian 700 MHz auction in 2014, where the bids were made public. The data provides evidence that bidders deviate significantly from straightforward bidding in the clock phase, which can restrict the bids they can submit in the supplementary phase. We show that such restrictions can have a significant negative impact on efficiency and revenue.     

Nash Equilibrium and Decentralized Negotiation in Auctioning Divisible Resources

We consider the problem of software agents being used as proxies for the procurement of computational and network resources. Mechanisms such as single-good auctions and combinatorial auctions are not applicable for the management of these services, as assigning an entire resource to a single agent is often undesirable and appropriate bund sizes are difficult to determine. We investigate a divisible auction that is proportionally fair. By introducing the notion of price and demand functions that characterize optimal response functions of the bidders, we are able to prove that this mechanism has a unique Nash equilibrium for an arbitrary number of agents with heterogeneous quasilinear utilities. We also describe decentralized negotiation strategies which, with approrpate relaxation, converge locally to the equilibrium point. Given an agent with a sequence of jobs, we show how our analysis holds for a wide variety of objectives.     

Auctioning countermeasures in the WTO

We offer a first formal analysis of auctioning retaliation rights within the WTO. We show that the auctions exhibit externalities among bidders, and we characterize equilibrium bidder behavior under alternative auction formats. If the violating country is prevented from bidding to retire the right of retaliation against it, then the possibility of “auction failure” arises, whereby no bids are made despite positive valuation by bidders. If the violating country is instead permitted to bid, then auction failure is precluded, and indeed the right of retaliation is always retired. We evaluate these different auction formats from normative (revenue, compliance, efficiency) standpoints.     

An Extension of Ausubel's Auction for Heterogeneous Discrete Goods

Ausubel's dynamic private‐values auction for heterogeneous discrete goods, Ausubel (2006), yields an efficient equilibrium outcome but it is designed for a limited class of environments. If bidders’ values for bundles of goods are not integers, then Ausubel's auction may end without allocating goods if no information on bidders’ values is available. In this paper, I extend Ausubel's auction for heterogeneous discrete goods to real‐valued quasilinear utility functions. The mechanism I propose reaches a Walrasian equilibrium price vector in finite ‘steps’ without any additional information on bidders’ values. In the extension of Ausubel's auction, truthful bidding constitutes an efficient equilibrium.     

On The Reference Point Effect of Reserve and Buy It Now Prices

In recent years, a trend in retail pricing has been to give consumers greater autonomy in setting their own prices, be it through auctions or other forms of participative pricing. Such consumer pricing autonomy often requires the seller to set limits in the form of price floors and price ceilings. Price floors and ceilings in our auction settings are referred to as reserve prices (RP) and Buy It Now (BIN) prices, respectively. We examine the effect of RP and BIN presence and magnitude on the number of bidders and ending price. Using auctions, we uncover consumers’ willingness to pay (WTP) through bids. WTP is malleable through reference cues. Our focus is on two such cues: BINs and RPs. Results of two field studies, augmented with a laboratory study, show that both BINs and RPs result in lower bidder entry, but have an overall positive effect on ending price. Furthermore, results show that RP is more effective than a comparable BIN magnitude and that these two pricing cues are substitutes. The study design allows the authors to rule out alternative explanations. Open RP and BIN's effect on ending price is due to a reference point effect rather than a price truncation effect. Thus, retailers can increase WTP through changing these reference cues and exploit a richer choice set over which to shape a malleable WTP. The quantification of the interaction between RP and BIN gives managers the ability to jointly take advantage of both RP and BIN.     

Reducing information asymmetry in the auctioning of non-perishable experience goods: The case of online wine auctions

We highlight the importance of reducing the perceived risk associated with information asymmetry for experience goods. We analyse a major online non-perishable experience good, wine, from the seller's perspective. The mechanism for lowering information asymmetry is the verification service offered by the auctioneer. By focusing on unsold items/lots, the wine and auction characteristics affecting the probability of a sale are identified. Results show that the verification of the wine's provenance increases the probability of sale by 5.7 percent and leads to an expected increase of 5.1 percent in the auction price. When both effects are combined, the increase in the expected revenue of the seller is 7.3 percent. We test and find no evidence of selection bias. Given the heterogeneity in wine prices, a quantile regression analysis shows how the results differ for high-priced wines compared to lower priced wines. Results highlight how the mechanisms to lower the degree of information asymmetry work both in attracting bidders to online auctions and encouraging bidders to submit higher bids.     

Stability Analysis in a Bertrand Duopoly with Different Product Quality and Heterogeneous Expectations

We study the local stability properties of a nonlinear Bertrand duopoly with vertical differentiation and heterogeneous players under the hypotheses of both covered and uncovered markets. In the former case, the unique pure strategy Nash equilibrium can undergo a flip bifurcation when the extent of consumer’s heterogeneity increases. In the latter, the quality differential determines the stability of prices over time. Numerical evidence is provided to show the occurrence of endogenous fluctuations.     

多属性逆向拍卖采购机制设计

全球市场环境不断向买方市场的转变,为企业利用逆向拍卖机制进行采购创造了条件。多属性逆向拍卖机制是采购拍卖中具有广泛应用价值的机制之一,在供应商成本和采购商效用具有可加属性特征的条件下,设计了一个基于模糊评价的多属性逆向拍卖机制,将各属性等级权重值设为供应行业提供此属性等级的平均边际成本,发现该机制是激励相容的较好机制。     

Mean‐field games with differing beliefs for algorithmic trading

Even when confronted with the same data, agents often disagree on a model of the real world. Here, we address the question of how interacting heterogeneous agents, who disagree on what model the real world follows, optimize their trading actions. The market has latent factors that drive prices, and agents account for the permanent impact they have on prices. This leads to a large stochastic game, where each agents performance criteria are computed under a different probability measure. We analyze the mean‐field game (MFG) limit of the stochastic game and show that the Nash equilibrium is given by the solution to a nonstandard vector‐valued forward–backward stochastic differential equation. Under some mild assumptions, we construct the solution in terms of expectations of the filtered states. Furthermore, we prove that the MFG strategy forms an ε‐Nash equilibrium for the finite player game. Finally, we present a least square Monte Carlo based algorithm for computing the equilibria and show through simulations that increasing disagreement may increase price volatility and trading activity.     

Duopolistic Price Competition with Captives

We extend the Bertrand duopolistic competition to include captives. These are consumers that have no choice between the suppliers. Usual population of shoppers are modeled performing a sequential search in order to decide where to buy a homogenous good. These two simple departures from the original setup have sharp consequences. First, we find that duopolistic price competition is not robust to inclusion of captives. The equilibrium results starkly differ and the only possible equilibrium now includes duopolists charging monopolistic prices. Second, addition of sequential search introduces multiplicity of pure strategy Nash equilibria. In this setup, we observe perverse optimal response to competitor's price changes. Notably, we find that the firm might want to reduce the price in response to the competitor's price increase, which is at odds with the usual undercutting principle. Third, we investigate the behavior of equilibrium prices depending on the heterogeneity in consumer risk attitudes. We find that the higher consumer heterogeneity with respect to acceptance of risky gambles leads to higher prices in equilibrium.     

Auction or agent (or both)? A study of moderators of the herding bias in digital auctions

Recent research has shown that buyers in digital auctions are susceptible to the herding bias—gravitation toward listings with existing bids and inconsideration of listings without any bids, manifested in categories of listings that are either coveted or entirely overlooked by buyers. This article investigates two specific types of moderators of herding bias: auction attributes (volume of listing activity, and posting of reservation price) and agent characteristics (seller and bidder experience), and increases our understanding of mechanisms underlying this bias. Practical implications for participants and organizers of digital auctions are discussed, and promising future research opportunities are highlighted.     

A Transaction Utility Approach for Bidding in Second-Price Auctions

In both the Vickrey and eBay auctions, bidding the reservation price is the optimal strategy within the conventional utility framework. However, in practice, buyers tend to bid less than their reservation prices, and bid multiple times, thus increase their bids, in the course of an auction. In this paper, we show that both underbidding and multiple bidding behaviors can be consistent with utility maximization, if buyer's utility incorporates a transaction utility (reference price dependent) component. Transaction utility is based on the difference between the buyer's reference price and actual price paid; it captures the perceived value of the deal. More specifically, we show that the optimal bid is lower than the reservation price, but higher than the reference price. Furthermore, buyer may re-bid (above the prior optimal level) if the reference price is revised upon observing a higher current price.     

酒店采购管理漏洞及解决方法的探讨

分析酒店采购管理,找出存在问题有实际意义。酒店采购管理存在采购员选择不当、制度不完善、成本高等漏洞,探讨出对采购人员实行心理监控、完善采购制度、降低成本、健全监控措施的策略。指出采购看似简单,但要做好,却是一门高深的艺术,成功的采购是整体和谐的反映。     

Mixed Equilibrium,Collaborative Dominance and Burning Money: An Experimental Study

We experimentally study three aspects of $2\times 2$ one-shot games with collaboratively dominant strategies: if subjects play according to the mixed Nash equilibrium; if the collaborative equilibrium has a focal point property; and if the burning money mechanism stimulates a collaborative behavior. First, our results show that players do not seem to play according to the mixed Nash equilibrium and that the collaborative equilibrium does not seem to have focal point properties. In fact, the subjects seem to prefer less risky strategies when compared to efficient ones. Our results also show that a burning money mechanism only helps players to collaborate when it transforms a collaborative profile of strategies into a collaborative equilibrium. This fact is justified because other burning money mechanisms will only help collaboration if the subjects were playing according to de mixed Nash equilibrium. Furthermore, even when burning money mechanisms improved the collaboration rate, such rate’s increase was smaller than the expected by the mixed Nash equilibrium.