网上拍卖竞买者出价来到过程的特征研究

本文利用从eBay网站收集的20个子类物品拍卖数据,通过基于MatLab编写的计算机程序,对竞买者出价来到过程的时段性、自相似性和幂律分布特征进行了研究,结果显示网上拍卖竞买者出价来到过程存在显著的后期出价现象,较长期限的拍卖能够减弱竞买者后期出价现象,且各类别拍卖的"冷淡期"呈现一定的规律;竞买者出价来到过程具有自相似性和幂律分布特征,受一自组织过程的驱动,但在不同拍卖时段有着不同的表现     

网上拍卖品的价格层级与类别对买方出价行为的影响——基于函数性数据聚类方法的分析

网上拍卖买方出价行为是网上参与者行为研究中的一个重要问题,但现有文献鲜有从统计视角就拍卖品的价格层级与类别对买方出价行为的影响进行研究.本文通过选择拍卖品种类和函数性数据聚类方法,对eBay26类物品拍卖和中国淘宝网珠宝类拍卖中买方的出价数据进行了函数性聚类分析,研究发现:在拍卖的不同时段,拍卖品的价格层级和类别对买方的出价行为会产生不同的影响,价格层级对买方出价行为的影响在中外网站呈现显著不同的特征.     

竞买者心理账户对网上拍卖结果的影响分析——来自孔夫子旧书网的证据

本文在心理账户研究范式下．分析网上拍卖中竞买者心理账户的变化过程。在研究拍卖心理账户初始金额的基础上．以孔夫子旧书网为数据来源,研究了竞买者心理账户对网上拍卖结果的影响。本文认为．小额起拍价与加价的违约率高于大额起拍价与加价的违约率．随机参与者的违约率大于专家的违约率。从而揭示了基于心理账户影响的网上拍卖竞买者违约的本质特征。     

我国网上拍卖竞买者出价行为特征分析——基于函数性稀疏数据聚类方法的实证研究

近年来,如何从个人角度分析竞买者出价行为成为研究难点.本文运用基于函数性稀疏数据聚类方法从竞买者个人角度定义了基于条件期望的距离矩阵,并结合多维尺度分析方法(MDS)和相平面图分析法对竞买者出价行为特征进行聚类分析.结果表明,按出价时间、金额、出价能量以及获胜概率可将竞买者分为显著的四类.其中,经验丰富型竞买者获胜概率最高,势在必得型竞买者获胜意愿最强烈,缺乏经验型竞买者退出竞拍时间较早导致获胜概率较低,围观型竞买者由于竞拍意愿不强烈所以获胜概率最低.     

网上拍卖雇佣出价行为的研究

雇佣出价是卖方雇佣出价人(或卖方)扮作买方故意人为地抬高被拍卖物品的竞价.雇佣出价通常发生在拍卖价值较高的物品且竞买人对这些物品估价差异较大的情况下,这样卖方就能从欺诈中获得较高的收益.为了预防和检查雇佣出价行为,本文给出了一个使得雇佣出价无利可图的拍卖机制.这一机制强调拍卖人的作用,拍卖人根据中标价和卖方保留价之差收取佣金,佣金率在不同的拍卖市场是不同的,确保雇佣出价无利可图.     

信誉、第三方标记与网上购买行为——基于淘宝网的实证研究

信誉积分和第三方标记是国内外在线零售市场经常使用的信任机制。本文通过搜索程序获取淘宝网上销售诺基亚5800手机的3060个商家的数据来验证信誉和第三方标记的作用。本文发现,在一口价而不是拍卖的情况下(1)价格对网上购买行为有负向关系,但这种影响受到信誉的调节信誉越高,价格对消费者网上购买行为的影响就越弱;(2)信誉对消费者网上购买行为有着显著的正向关系,这种关系受到保障型和慈善型第三方标记的调节这些标记越多,信誉对消费者购买行为的影响越大;(3)促销型第三方标记与购买行为有着正向关系,而便利型第三方标记与购买行为无显著关系。     

网上一元竞拍成交价格影响因素相关性研究:基于eBay网络Mp3竞拍的实证

对网络拍卖现实成交及网络成交进行系列研究有着重要的理论意义和现实意义。文章是网络拍卖系列研究之一,选择影响网络拍卖成交的重要因素——网络成交价作为研究变量,对网络成交价的影响因素进行了相关性研究,并以中国最大的C2C网站eBay易趣网上Mp3拍卖为实证。     

网上拍卖系统的风险与控制

网上拍卖比传统拍卖具有更高的风险。因此 ,网上拍卖系统需要有更加严格完善的控制。本文首先分析了网上拍卖系统可能出现的各种风险 ,然后较深入地探讨了防范网上拍卖系统风险的各种控制措施。     

我国手机用户网上信息行为影响因素研究

我国手机用户数量逐年攀升,运用手机上网也成为手机用户上网的新选择。文章介绍了移动互联网的发展情况,对我国手机用户网上信息行为进行分析,探讨了影响手机用户网上信息行为的内外界因素,为促进手机用户上网、发展移动互联网以满足用户信息需求提出了对策与建议。     

创新竞赛中锦标赛与拍卖激励机制的比较研究:实验的方法

何种激励方式能更好地促进创新,是理论界和实务界共同关注的问题。本文采用实验研究的方法,分析创新竞赛中锦标赛和拍卖两种激励机制对员工努力水平及收益的影响。利用对88个被试进行的8个实验,本文获得了如下研究结论:(1)锦标赛机制下,单独的竞赛规模因素不会对被试的努力水平产生显著影响,但对被试收取一定的入场费后,随着规模的扩大,被试的努力水平会有所降低;(2)在拍卖机制下,规模因素对被试的努力水平影响显著,且规模较小时是否限制竞价区间对被试竞价值没有显著的影响;(3)对两种激励机制下被试努力水平的比较分析发现,在竞赛规模较小时,拍卖机制下被试的努力水平和收益都优于锦标赛机制。规模较大时,锦标赛和拍卖机制的激励效果没有显著差异。     

Non-bidding equilibrium in an ascending core-selecting auction

This paper investigates the perfect Bayesian equilibrium in an ascending-price core-selecting auction, which is recently used in some countries? spectrum license auctions. We suppose that there are two identical items, two small bidders, and one large bidder. The small bidders demand only one unit of the item, whereas the large bidder wants both units. Package bidding ensures that the large bidder faces no exposure problem and behaves truthfully. However, one of the small bidders stops bidding at the beginning in the equilibrium. Although small bidders generally face the free-rider problem and have incentives to underbid, once a bidder is the only small one remaining, he bids truthfully. Stopping early induces the remaining bidder to behave truthfully. Hence, each small bidder wants to be the first to stop bidding. The free-rider problem is considerably mitigated when there are many small bidders.     

Bidding behavior in competing auctions: Evidence from eBay

Much of the existing auction literature treats auctions as running independently of one another, with each bidder choosing to participate in only one auction. However, in many online auctions, a number of substitutable goods are auctioned concurrently and bidders can bid on several auctions at the same time. Recent theoretical research shows how bidders can gain from the existence of competing auctions, the current paper providing the first empirical evidence in support of competing auctions theory using online auctions data from eBay. Our results indicate that a significant proportion of bidders do bid across competing auctions and that bidders tend to submit bids on auctions with the lowest standing bid, as the theory predicts. The paper also shows that winning bidders who cross-bid pay lower prices on average than winning bidders who do not.     

Designing Multi-unit Multiple Bid Auctions: An Agent-based Computational Model of Uniform, Discriminatory and Generalised Vickrey Auctions

Multi-unit auctions are being used by public agencies to allocate resources and to purchase services. These auctions resolve the lumpy bid problem inherent in single-bid auctions by allowing bidders to submit a supply or demand schedule. However, the choice of pricing formats for multi-unit auctions is controversial. Neither economic theory nor laboratory experiments depict a complete picture of how alternative pricing formats perform in terms of budgetary or allocative efficiency. This paper constructs an agent-based computational model to compare uniform, discriminatory and generalised Vickrey pricing formats under different degrees of competition and heterogeneity in the bidder population.     

网络团购拍卖中竞标者队列研究

通过分析网络团购拍卖机制下的竞标者等待达到拍卖保留价格现象,提出网络团购拍卖过程中存在竞标者队列,并揭示了竞标者队列的性质及其对网络团购拍卖机制设计的影响。研究指出:网络团购拍卖存在较大数量的成功竞标者,这些成功竞标者因需等待拍卖最终成交而形成竞标者队列;拍卖方对竞标者队列进行的服务与成批服务的排队系统相似,但也存在差异;拍卖方可优化网络团购拍卖机制,以保证获得拍卖收益,并减少在服务过程中出现的队列拥塞现象的发生。     

Almost common values auctions revisited

In almost common-value auctions one bidder (the advantaged bidder) has a valuation advantage over all other (regular) bidders. It is well known that in second-price auctions with two bidders, even a slight private-value advantage can have an explosive effect on auction outcomes as the advantaged bidder wins all the time and auction revenue is substantially lower than in a pure second-price common-value auction. We explore the robustness of these results to the addition of more regular bidders in second-price auctions, and the extent to which these results generalize to ascending-price English auctions in an effort to provide insight into when and why one ought to be concerned about such slight asymmetries.     

The value of an informed bidder in common value auctions

I compare two information structures in a common value first-price auction with two bidders: In one, each of the two bidders knows only his own signal about the value of the object, and in the other, one of the bidders learns his opponent's signal as well. Gaining the additional information in the second information structure makes the informed bidder worse off if the value is submodular in the bidders' signals and better off if it is supermodular. If the value is supermodular, then the seller's revenue tends to be lower with the informed bidder than without.     

Collusion in one-shot second-price auctions

Summary. Most of the literature on collusive behavior in auctions ignores two important issues that make collusion difficult to sustain at least in one-shot interactions: the detection of cheating and the verification of bids. Colluding bidders may deceive each other by using shill bidders. Also, if the identities of the bidders and their bids are not published then it would be difficult to verify the bid of a colluding bidder. This paper addresses these problems in one shot second price auctions where one bidder offers another bidder a side payment in exchange for not participating in the auction, while the number of other bidders is stochastic. In spite of the barriers to collusion mentioned above, a simple side payment mechanism which depends only on the auction price is introduced. It induces a successful collusion, eliminates the verification problem, provides no incentive for the use of shill bidders and guarantees that the proponent obtains ex-post non-negative payoff. The colluding bidders are ex-ante strictly better off compared with the competitive case, irrespective of their types.Received: 27 November 2002, Revised: 28 January 2005, JEL Classification Numbers: C72, D44, D82.Yair Tauman: Correspondence toWe would like to thank an anonymous referee for very valuable comments and suggestions that significantly improved the paper. We thank Shmuel Zamir for a helpful discussion.     

Exploring pricing rules in combinatorial sealed-bid auctions

The allocation of public goods such as the radio spectrum is a difficult task that the government must face. Currently, auctions are becoming an important tool to deal with this duty. In this context, the rules that the auctioneer establishes are particularly relevant, as the final outcome depends on them. When auctioning many related items, such as spectrum licenses, the bidders’ values for one item may depend on the number of items already obtained (complements and substitutes items). In such circumstances, combinatorial auctions are the most appropriate alternative for allocating lots. This paper analyzes the implications of selecting a particular pricing mechanism on the final result in a combinatorial sealed-bid auction. The following pricing rules are selected: the first-price mechanism, the Vickrey–Clarke–Groves (VCG) mechanism, and the bidder–Pareto–optimal (BPO) core mechanism, a core-selecting auction. To test these pricing rules, a simulator of the auction model has been developed. Then, to tackle the complex problem of simulating bidders’ behavior, a co-evolutionary system has been designed to identify improved strategies. The results revealed that the first-price mechanism yields inefficient outcomes and a notable reduction in the seller's revenues. Both the VCG and BPO mechanisms yield outcomes that are closer to the efficient allocation, and differences in revenues are affected by the presence of asymmetries.     

Bidding in a possibly common-value auction

We analyze a second-price auction with two bidders in which only one of the bidders is informed as to whether the object is valued commonly. We show that any equilibrium strategy of the bidder who is uninformed must be part of an equilibrium when both bidders instead know that the auction is not common value, regardless of the way in which the values are different. We derive sufficient conditions for equilibrium existence.     

Strategic ignorance in a second-price auction

Suppose that bidders may publicly choose not to learn their values prior to a second-price auction with costly bidding. All equilibria with truthful bidding exhibit bidder ignorance when the number of bidders is sufficiently small. Ignorance considerations also affect the optimal reserve price.