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Beil, Damian. "Two topics in online auctions." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/17578.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2003.Includes bibliographical references (p. 83-85).
This thesis studies two operations management topics in online auctions, and is divided into two parts. Motivated by the increasing use of ShopBots to scan Internet auctions, the first part of the thesis analytically examines whether or not two competing auctioneers selling the same commodity should share, or pool, some or all of their bidders. Under pooling, the bidding population is represented by three compartments: bidders dedicated to auction 1, bidders dedicated to auction 2, and pooled bidders participating in both auctions simultaneously. Under a bidder strategy shown to induce a Bayesian equilibrium, a closed form expression for the auctioneers' expected revenue under pooling is found, and pooling is recommended where it produces a greater expected revenue than no pooling (i.e., our objective is revenue maximization). Pooling is generally found to be beneficial as long as the two auctions are not too asymmetric and the underlying valuation distribution has certain concavity characteristics. Asymptotic order statistic arguments are used where explicit characterizations are intractable. The second part of the thesis considers a manufacturer who uses a reverse, or procurement, auction to determine which supplier will be awarded a contract. Each bid consists of a price and a set of non-price attributes (e.g., quality, lead time). The manufacturer is assumed to know the suppliers' cost functions (in terms of the non-price attributes). We analyze how the manufacturer chooses a scoring rule (i.e., a function that ranks the bids in terms of the price and non-price attributes) that attempts to maximize his own utility. Under the assumption that suppliers submit their myopic best-response bids (i.e., they choose their minimum-cost bid to achieve any given score), our proposed scoring rule indeed maximizes the manufacturer's utility within the open-ascending format.
(cont.) The analysis reveals connections between the manufacturer's utility maximization problem and various geometric aspects of the manufacturer's utility and the suppliers' cost functions.
by Damian Ronald Beil.
Ph.D.
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Gupta, Shobhit. "Buyout prices in online auctions." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36223.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2006.Includes bibliographical references (p. 149-154).
Buyout options allow bidders to instantly purchase at a specified price an item listed for sale through an online auction. A temporary buyout option disappears once a regular bid above the reserve price is made, while a permanent option remains available until it is exercised or the auction ends. Buyout options are widely used in online auctions and have significant economic importance: nearly half of the auctions today are listed with a buyout price and the option is exercised in nearly one fourth of them. We formulate a game-theoretic model featuring time-sensitive bidders with independent private valuations and Poisson arrivals but endogenous bidding times in order to answer the following questions: How should buyout prices be set in order to maximize the seller's discounted revenue? What are the relative benefits of using each type of buyout option? While all existing buyout options we are aware of currently rely on a static buyout price (i.e. with a constant value), what is the potential benefit associated with using instead a dynamic buyout price that varies as the auction progresses?
(cont.) For all buyout option types we exhibit a Nash equilibrium in bidder strategies, argue that this equilibrium constitutes a plausible outcome prediction, and study the problem of maximizing the corresponding seller revenue. In particular, the equilibrium strategy in all cases is such that a bidder exercises the buyout option provided it is still available and his valuation is above a time-dependent threshold. Our numerical experiments suggest that a seller may significantly increase his utility by introducing a buyout option when any of the participants are time-sensitive. Furthermore, while permanent buyout options yield higher predicted revenue than temporary options, they also provide additional incentives for late bidding and may therefore not be always more desirable. The numerical results also imply that the increase in seller's utility (over a fixed buyout price auction) enabled by a dynamic buyout price is small and does not seem to justify the corresponding increase in complexity.
by Shobhit Gupta.
Ph.D.
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Peterson, Madeleine. "New Technology, Old Ways? The Gender Price Discount in Online Contemporary Art Auctions." Scholarship @ Claremont, 2019. https://scholarship.claremont.edu/scripps_theses/1265.
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There is evidence there is a global gender price gap in traditional global art auctions. Taking into account recent technological advances in the secondary art market, this study examines if there is a gender gap for the sale prices of female artists’ work in the contemporary, online art auction market. The analysis uses a unique data set of art works sold in Christie’s Online-Only Auctions for the year of 2018. We regress measures of price on gender and controls for various characteristics of the art work and artist. We find that while there is discount in prices of 17% for artwork created by female artists, further analysis indicates the difference is not necessarily the result of bidder’s biased prices, but rather rooted in the pre-sale estimates given by the auction houses.
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Parker, Thomas Glenn. "ONLINE-REVERSE-AUCTIONS AND THE BUYER-SUPPLIER RELATIONSHIP: THE EFFECTS OF ONLINE-REVERSE-AUCTION DESIGN ON SUPPLIER COMMITMENT AND SUPPLIER TRUST." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/192.
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Industrial online-reverse-auctions have become a common procurement strategy used by many firms to reduce the cost of purchased goods and services. The advantages of online-reverse-auctions include significant price reductions, increased purchasing and selling efficiencies, and access to new supply and purchasing markets. Despite these benefits, practitioners and academics alike have raised concerns with respect to the impact of online-reverse-auctions on the buyer-supplier relationship. Previous research suggests that the parameters and characteristics of an online-reverse-auction can influence the perceptions of online-reverse-auction participants. This dissertation investigates this phenomenon by examining how the design of an online-reverse-auction influences the supplier's perception of the buyer-supplier relationship. Specifically, this research considers the effects of online-reverse-auction design in terms of the independent variables of auction control, auction bid visibility, and auction award rules and the dependent variables of supplier commitment to the buyer and supplier trust in the buyer. Using a 2 x 2 x 2 quasi-experimental design and the statistical technique of MANCOVA, this study tests hypotheses related to how different online-reverse-auction design characteristics influence supplier commitment to the buyer and supplier trust in the buyer. The results of the study suggest that the type of online-reverse-auctions buyers utilize can have an impact on supplier perceptions of the buyer supplier relationship. Overall, the result suggest that supplier trust is influenced by the type of auction design buyers utilize, however, supplier commitment is not. Auctions utilizing third party auction providers, partial bid visibility, and post auction negotiations tended to result in higher levels of trust on the part of suppliers. This study makes a contribution to the literature in the following areas. First, this study is one of only a handful of empirical studies examining the effects of online-reverse-auction designs on the buyer-supplier relationship. While a considerable debate exists within the literature concerning the pros and cons of online-reverse-auctions, little empirical work exists. This study makes a contribution by providing insight with respect to how online-reverse-auction designs influence supplier perceptions of the buyer-supplier relationships. Secondly, this analysis considers the buyer-supplier relationship in terms of commitment and trust. Previous studies have largely neglected these constructs despite their prominence in the buyer-supplier relationship literature. Finally, given that the use of online-reverse-auctions seems well entrenched in the purchasing strategies of many buying organizations; this study provides guidance for the design of online-reverse-auctions such that buyers can potentially reduce the negative aspects of the process.
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Namazi, Alireza. "Emergent behavior and criticality in online auctions." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976716739.
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Ødegaard, Fredrik. "Analytical and empirical models of online auctions." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/1615.
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This thesis provides a discussion on some analytical and empirical models of online auctions. The objective is to provide an alternative framework for analyzing online auctions, and to characterize the distribution of intermediate prices. Chapter 1 provides a mathematical formulation of the eBay auction format and background to the data used in the empirical analysis. Chapter 2 analyzes policies for optimally disposing inventory using online auctions. It is assumed a seller has a fixed number of items to sell using a sequence of, possibly overlapping, single-item auctions. The decision the seller must make is when to start each auction. The decision involves a trade-off between a holding cost for each period an item remains unsold, and a cannibalization effect among competing auctions. Consequently the seller must trade-off the expected marginal gain for the ongoing auctions with the expected marginal cost of the unreleased items by further deferring their release. The problem is formulated as a discrete time Markov Decision Problem. Conditions are derived to ensure that the optimal release policy is a control limit policy in the current price of the ongoing auctions. Chapter 2 focuses on the two item case which has sufficient complexity to raise challenging questions. An underlying assumption in Chapter 2 is that the auction dynamics can be captured by a set of transition probabilities. Chapter 3 shows with two fixed bidding strategies how the transition probabilities can be derived for a given auction format and bidder arrival process. The two specific bidding strategies analyzed are when bidders bid: 1) a minimal increment, and 2) their true valuation. Chapters 4 and 5 provides empirical analyzes of 4,000 eBay auctions conducted by Dell. Chapter 4 provides a statistical model where over discrete time periods, prices of online auctions follow a zero-inflated gamma distribution. Chapter 5 provides an analysis of the 44,000 bids placed in the auctions, based on bids following a gamma distribution. Both models presented in Chapters 4 and 5 are based on conditional probabilities given the price and elapsed time of an auction, and certain parameters of the competing auctions. Chapter 6 concludes the thesis with a discussion of the main results and possible extensions.
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Anthony, Patricia. "Bidding agents for multiple heterogeneous online auctions." Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/257838/.
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Due to the proliferation of online auctions, there is an increasing need to monitor and bid in multiple auctions in order to procure the best deal for the desired good. To this end, this thesis reports on the development of a heuristic decision making framework that an autonomous agent can exploit to tackle the problem of bidding across multiple auctions with varying start and end times and with varying protocols (including English, Dutch and Vickrey). The framework is flexible, configurable, and enables the agent to adopt varying tactics and strategies that attempt to ensure that the desired item is delivered in a manner consistent with the user's preferences. Given this large space of possibilities, a genetic algorithm is employed to search (offline) for effective strategies in common classes of environment. The strategies that emerge from this evolution are then codified into the agent's reasoning behaviour so that it can select the most appropriate strategy to employ in its prevailing circumstances. The proposed framework has been implemented in a simulated marketplace environment and its effectiveness has been empirically demonstrated.
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Radkevitch, Ulad. "Online reverse auctions for procurement of services /." Rotterdam : Erasmus Research Institute of Management, 2008. http://hdl.handle.net/1765/13497.
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VINIJSORN, KRIT. "Art auctions on eBay : An empirical study of bidders’ behavior on eBay." Thesis, Högskolan i Jönköping, Internationella Handelshögskolan, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-15890.
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This paper explores the determinants of the number of bidders and final price of 1900s oil paintings auctioned by resellers or dealers on eBay art auctions. We find that starting price has negative effect on bidder’s decision whether to enter the auctions or not while seller reputation variables such as seller´s feedback, being top rate seller has a positive effect. Furthermore, auction theory is introduced to study the bidder´s behavior through auction characteristics and final price. We find that, interestingly, the seller´s reputation variables have no significant effect to the final price and the number of bidders has positive effect toward final price of art work. This evidence means that art auctions on eBay has a private value auctions characteristic. However, some specific characteristics of online auctions, which are the last minute bidding and the presence of experienced bidders, significantly affect the final price. Being an experienced winner or using last minute bidding as a strategy substantially pay more than inexperienced winners or winners who do not use last minute bidding in auctioned painting. This could result from different preference of bidders toward auctioned painting or information on which each bidder is holding.
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Rameson, Tyler J. (Tyler James) 1974. "Online auctions in procurement : the cost/goodwill tradeoff." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9157.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Engineering Systems Division, 2000.Includes bibliographical references (leaf 44).
Industry is rapidly adopting online auctions. Many of these auctions are occurring in the procurement of component supplies. While there are tremendous expectations for this technology, there is little data or study looking at the implications of the technology. This thesis aims to provide some insight into this topic. Primarily using data collected in a study of auctions in the procurement of automotive components, this thesis looks at the costs and benefits of using online auctions in procurement. The thesis specifically addresses the cost vs. supplier goodwill tradeoff present in procurement auction. After quantifying these variables and answering associated questions, the thesis provides a framework for evaluating the use of online auctions in industry in general. The thesis concludes with a list of suggested further research into this important subject.
Tyler J. Rameson.
M.Eng.
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Shahriar, Quazi Hasnat. "Auctions with Buy Prices." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194708.
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The major internet auction sites eBay and Yahoo have developed innovative hybrid auction designs that incorporate buy prices. My dissertation focuses on the Buy It Now (BIN, hereafter) version of the auctions on eBay, the largest online auction site. The BIN hybrid auction combines a standard ascending bid auction with a posted-price offer. A seller in a BIN auction lists his auction with a "buy price". A bidder may purchase the item immediately at the buy price and end the auction. If he places a bid instead, the option to purchase the item at the buy price disappears and the subsequent bidders participate in the standard eBay auction. This auction format has been very popular with both buyers and sellers. In 2005 eBay's sales in fixed price platform (BIN and Half.com) totaled $13.8 billion, which was 33.1% of eBay's total sales.The dissertation explores the BIN auctions using theory, experiments and field data. Chapter 1 theoretically analyzes BIN auctions within the common values framework. An equilibrium is characterized, shown to exist, and the revenues generated by BIN and standard eBay auctions are compared. Chapter 2 compares the bidding behavior and the revenue implications of BIN auctions in lab experiments under common and private value assumptions. The third develops an "incomplete" theoretical model of BIN auctions within the private values framework. An "incomplete" empirical specification is derived and then field data collected from eBay's BIN auctions are used to estimate the primitives of the model, including the bidders' risk aversion and time preference. I then explore how heterogeneity of sellers and items influence these primitives. Chapter 1 (Common Values Auctions with a Buy Price: the case of eBay): Several explanations for the popularity of buy price have been provided for independent private value auctions. Risk aversion and impatience of either the bidders or the seller have mainly been used to explain the popularity of buy prices in IPV models. This paper, using a pure common value framework, models auctions with eBay-style "temporary" buy prices, when the bidders and the seller are either risk neutral or risk averse. It characterizes equilibrium bidding strategies in a general setup and then analyzes a seller's incentive to post a buy price when there are two bidders. When bidders are either risk neutral or risk averse there is no incentive to post a buy price for a risk neutral seller. But when the seller is risk averse, a suitably chosen buy price can raise the seller's expected utility when the bidders are either risk neutral or risk averse. Chapter 2 (An Experimental Study of Auctions with a Buy Price Under Private and Common Values): We use experiments to examine several predictions from the theoretical studies of buy prices. The theoretical predictions from Wooders and Reynolds (2003) and Chapter 1 show that the introduction of a buy price causes the seller's revenue to move in opposite directions in private value and common value settings. Meanwhile, Mathews and Katzman (2006) find that risk averse sellers might find buy prices advantageous because they reduce the variance in seller revenue in eBay auctions with risk-neutral bidders. The lab experiments are used to answer three key questions. (a) Can a buy price raise seller revenue and lower the variance of seller revenue in an independent private value auction? (b) Does a buy price lower seller revenue in common value auctions? (c) If the theoretical predictions do not hold, can a behavioral model explain the patterns observed in the data? Using a between-subjects design the results show that the use of a buy price has a positive and statistically significant effect on seller revenue in private value auctions. The buyers are risk averse. The estimate of the Constant Absolute Risk Aversion (CARA) index of 1.11 for the bidders is equivalent to a Constant Relative Risk Aversion (CRRA) index of 0.62 which is centered within the range of other estimates of relative risk aversion. As predicted by the theory when buyers are risk averse, the use of a buy price yields a statistically significant reduction in the variance of seller revenue. Hence, as predicted, the use of a buy price is advantageous to the seller when either the bidders or the seller are risk averse. The results for common value auctions are inconsistent with the theoretical predictions. Use of a buy price did not lower seller revenue, and the bidders' behavior departed from theoretical predictions in several respects. As a result, we develop and estimate a behavioral model of common value BIN auctions based on the winner's curse and overweighting of a bidder's private information. We find statistically significant evidence of overweighting of the bidder's own signal and estimated a CARA index of 0.001. This behavioral model explains all the departures from the rational model we found in the common values experiments. Chapter 3 (The Buy-it-now Option, Risk Aversion, and Impatience in an Empirical Model of eBay Bidding): Haile and Tamer (2003) first used an incomplete econometric model in an auction context, assuming that bidders bid up to their values and do not allow an opponent to win at a price they are willing to beat. Canals-Cerda and Pearcy (2004) used a similar incomplete econometric model to study eBay auctions while adding the assumption that the maximum of all the bids placed by the bidder with the second highest value is exactly equal to his value. Chapter 3 extends these incomplete models to eBay's BIN auctions. We develop and estimate an equilibrium model for BIN independent private value auctions with a stochastic and unknown number of potential bidders who enter the auction sequentially. In the model risk averse and time impatient bidders buy at the BIN price because it allows them to avoid the uncertainties and delay of the ascending bid auction that takes place if no one chooses the BIN option. As a result, the bidders' decisions to choose the BIN option in BIN auctions of different lengths can be used to identify the bidders' risk aversion and time preference parameters. Our model is "incomplete" in the sense that we do not impose any stylized structure on bidding in the ascending bid auction and, although bid revision is allowed, the process is not explicitly described. Our "incomplete" econometric model uses a partial likelihood approach proposed by Cox (1975) that allows the analysis to bypass modeling bidding and the bid revision process. The model is estimated using a new data set of 3245 eBay auctions of Pentium-3 laptops that ran between 22 July to 10 August 2005.
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Bewsell, Glenn Robert Information Systems Technology & Management Australian School of Business UNSW. "An investigation of mechanisms that impact trust: a domain study of online auctions." Publisher:University of New South Wales. Information Systems, Technology & Management, 2008. http://handle.unsw.edu.au/1959.4/41220.
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This thesis investigated trust over the Internet to seek a better understanding of trust and ways to increase trust in online transactions. The focus of this investigation was consumer-to-consumer transactions at online auctions where key actors were virtually anonymous to each other. The perceptions of a broad range of online auction community members support this thesis. Normative and grounded theoretical perspectives of trust and factors that affected trust were considered, compared and contrasted as part of this research. Concept mapping and the Theory of Planned Behaviour (TPB) were used to underpin the grounded theoretical perspective of trust developed as part of this thesis. Online auction cases were selected and analysed to check the grounded theoretical perspective of trust developed. This thesis provided a better understanding of trust, provided new insights into trust and distrust, added to the body of theory for trust and identified ways to increase trust in online transactions. This thesis provided better understandings of: trust; moral obligations; network decision structures; power; fairness; and perceived behavioural controls at online auctions. A grounded theoretical model of trust based in TPB was developed that was specific to online auctions. This model of trust developed appeared to provide clearer and richer insights into online auction trust. The model of trust developed identified factors and constructs that affected trust rather than the magnitude of any affects. The model developed and findings of this thesis can be applied to new or specific online auction sites to help practitioners build better online environments to encourage more people to transact rather than just browse online. The grounded theoretical perspective of trust and findings of this thesis may be relevant to other online consumer-to-consumer transactional environments.
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Nagy, Lindsey Danielle. "Mitigating Sniping in Internet Auctions." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/293592.
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My dissertation discusses a mechanism that thwarts sniping and improves efficiency in ascending Internet auctions with fixed ending times, specifically eBay. The first research chapter proposes a design of the bidding mechanism and the second chapter tests the effectiveness of the mechanism in a controlled environment. In addition, it presents an innovative theoretical representation of the eBay bidding environment. The first chapter investigates theoretically whether sellers can improve their profits in eBay-like auctions via the implementation of bidder credits. The analysis predicts that providing a credit, similar to a coupon or discount, for early bidding can thwart sniping and increase seller profit. The paper formulates and analyzes a multi-stage auction model with independently and identically distributed private values, where bidders place proxy bids. I show that sniping can emerge as a Bayesian-Nash equilibrium strategy so long as late bids run the risk of not being successfully received by the auctioneer; extending the prior work of Ockenfels and Roth. This equilibrium is inefficient and yields the worst outcome for sellers. The proposed credit mechanism awards a single early bidder a reduction, equal to the value of the credit, in the final price if he wins the auction. The optimal credit satisfies two necessary conditions; first, it increases seller ex-ante profit and second, it incentivizes bidders to deviate from the sniping equilibrium. Relative to the surplus generated by the sniping equilibrium, implementing the credit increases seller surplus and improves welfare. The second chapter experimentally investigates the effectiveness of the credit mechanism. In particular, it compares bidding strategies, seller profit, and overall efficiency in auction environments similar to eBay with and without credit incentives. I observe a significant decline in the frequency of sniping when subjects have the opportunity to receive the credit. The credit also improves auction efficiency primary because subjects overbid in auctions with the credit regardless of which subject has the credit. A within-subjects design allows me to directly compare differences across treatments conditional on the subjects being snipers. Auctions with snipers yield significantly lower profits to sellers because non-sniping rivals are bidding less aggressively when competing against a sniper.
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Roll, Bruce A. "Online reverse auctions : a pricing tool for government contracting /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA386693.
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Thesis (M.S. in Management) Naval Postgraduate School, Dec. 2000.Thesis advisors, Nissen, Mark E. ; Gates, William R. "December 2000." Includes bibliographical references (p. 63-64). Also available online.
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Wang, Shanshan. "Exploring and modeling online auctions using functional data analysis." College Park, Md. : University of Maryland, 2007. http://hdl.handle.net/1903/6962.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2007.Thesis research directed by: Mathematics. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Shiu, Lawrence Mateo. "Can arbitration resolve disputes arising from online activity? online auctions and other related activities /." access abstract and table of contents access full-text, 2008. http://libweb.cityu.edu.hk/cgi-bin/ezdb/dissert.pl?ma-slw-b23454325a.pdf.
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Thesis (M.A.)--City University of Hong Kong, 2008."Submitted to School of Law in partial fulfillment of the requirements for the degree of Master of Arts." Title from PDF t.p. (viewed on June 1, 2009) Includes bibliographical references.
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Hou, Jianwei. "Price variations in online auctions : evidence from a thick market /." Full text available from ProQuest UM Digital Dissertations, 2006. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1410676371&SrchMode=1&sid=3&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1218562039&clientId=22256.
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Wojciechowska, Olga. "Online auctions : examination of bidders' strategies : theory and data analysis." Thesis, University of Warwick, 2018. http://wrap.warwick.ac.uk/105556/.
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This PhD thesis is concerned with buyers' strategies in sequential and concurrent auctions. It deals with both the theoretical viewpoint and data analysis of online consumer auctions. The first chapter contains a newly developed model of sequential auctions with overlapping generations of bidders. The emphasis is on the existence of learning from observed past prices. With the addition of overlapping generations the learning happens through two channels: updating on valuations and expectation of composition of bidders with different horizons lengths. The model shows how this happens on the micro level, where expected distributions of bids are updated. In the following chapter, the predictions of theoretical models of sequential auctions together with learning are tested empirically. It is shown that bidders adjust their bids as a consequence of learning as predicted by the model. Bid discounting is also observed in the data. The following empirical chapter uses the bids data from online auctions to perform multinomial logit estimations. Individual choice model allows to analyze the aspects that attract bidders to particular auctions out of many very similar ones available. A unique dataset that contains data from many auctions for the same product is used in this new way. Dynamic aspects of auctions such as the number of bidders and bids are shown to play a role in auction choice. Overall, there are three approaches to the empirical analysis of bidders strategies, based on the same dataset. It is shown that with appropriate adjustments the data collected from online auctions can be used in different formats to answer various questions.
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Frark, Philipp. "Legal Issues in Online Auctions in Germany and the U.S.A." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/4614.
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Because of the multiplicity of commercial operations which are transacted by way of Internet Auction it is unavoidable that some of them end up in front of the court. The number of legal procedures and judicial decisions around Internet Auctions is consequentially increasing, because there is more and more business transacted by way of Internet Auction. These judgments were rendered in various fields of law so that one cannot say that there exists a special "Law of Internet Auctions". In fact there are well known problems in traditional fields of law presented in a new context. In the following this paper will examine these Legal Issues in the context of Internet Auctions and deal with the law of the United States of America and Germany with respect to the question how these countries handle these legal issues. It will afterwards go on with a comparative view as to the legal practices of the two countries, then address the International Civil Procedural Law and lastly close with a final statement.
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Karakaya, Gulsah. "Approaches For Multi-attribute Auctions." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610780/index.pdf.
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There is a growing interest in electronic auctions in the literature. Many researchers work on the single attribute version of the problem. Multi-attribute version of the problem is more realistic. However, this brings a substantial difficulty in solving the problem. In order to overcome the computational difficulties, we develop an Evolutionary Algorithm (EA) for the case of multi-attribute multi-item reverse auctions.
We generate the whole Pareto front using the EA. We also develop heuristic procedures to find several good initial solutions and insert those in the initial population of the EA. We test the EA on a number of randomly generated problems and compare the results with the true Pareto optimal front obtained by solving a series of integer programs.
We also develop an exact interactive approach that provides aid both to the buyer and the sellers for a multi-attribute single item multi round reverse auction. The buyer decides on the provisional winner at each round. Then the approach provides support in terms of all attributes to each seller to be competitive in the next round of the auction.
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O'Regan, Ryan Timothy. "A Look at the Game Theory of Online Auctions: The Choice Between End-Time Formats on Yahoo! Auctions." Thesis, Boston College, 2005. http://hdl.handle.net/2345/406.
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Thesis advisor: Hideo KonishiOnline auctions have many different formats. Each of these affect the ways in which users bid strategically. One example of this is the end-time format. Some sites, like eBay, use a hard close, under which there is a strict end-time and the highest bidder at that time wins. Others, like Amazon, have an extended end-time format. It has been shown that these differences do, in fact, appear to change how bidders behave. This paper uses data obtained from Yahoo! Auctions, where both formats are used, to examine the impact these differences have on the final price of an auction
Thesis (BA) — Boston College, 2005
Submitted to: Boston College. College of Arts and Sciences
Discipline: Economics Honors Program
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Zhong, Fang. "Empirical analyses of online procurement auctions - business value, bidding behavior, learning and incumbent effect." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19765.
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Thesis (Ph.D)--Management, Georgia Institute of Technology, 2008.Committee Chair: Wu, D.J.; Committee Member: Keskinocak, Pinar; Committee Member: Narasimhan, Sridhar; Committee Member: Toktay, Beril; Committee Member: Zhang, Han.
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Eddhir, Ahmed. "The value of reputaion [sic] in online auctions evidence from eBay /." Connect to this title online, 2009. http://etd.lib.clemson.edu/documents/1249066271/.
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Majadi, Nazia. "Real-Time Detection and Prevention of Shill Bidding in Online Auctions." Thesis, Griffith University, 2019. http://hdl.handle.net/10072/382740.
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Online auctions have become one of the most popular and convenient buying and selling
media in e-commerce. However, the amount of auction fraud increases with the popu-
larity of online auctions. This thesis examines one of the most severe types of auction
fraud, referred to as shill bidding, where fake bids are used to arti cially in
ate an item's
nal price. Shill bidding is strictly prohibited in online auctions because it forces honest
bidders to pay more for their products. Researchers have proposed several mechanisms
to detect shill bidding once an auction has nished. However, if shill bidding is not
detected during an auction, an innocent bidder (i.e., the winner of the auction) can
potentially be cheated by the end of the auction. Therefore, it is necessary to detect
and verify potential shill bidding in real-time (i.e., while an auction is in progress).
This thesis proposes and implements several novel techniques for combating shill
bidding in real-time. The e ectiveness of these techniques is shown through applica-
tions on simulated and commercial auction datasets. The research results include the
following:
1. Existing literature conducted on shill bidding detection and prevention has been
studied. The research gaps that remain as research challenges in this particular
domain have been identi ed. The research ideas on the detection and prevention
of shill bidding have been summarised from past literature. This will help future
researchers to develop more trustworthy online auction environments.
2. Testing the e ectiveness of newly proposed fraud countermeasures is a very chal-
lenging task. The reason is the lack of auction data availability as commercial
online auction houses (e.g., eBay, Yahoo! Auctions, etc.) do not share their data
for privacy concerns. Furthermore, there is no way to evaluate the performance of
fraud detection mechanisms. To accomplish these research goals, an online auc-
tion system, referred to as uAuction, has been developed. uAuction has been
used to test the e ectiveness of newly proposed shill bidding detection algorithms.
3. A real-time shill bidding detection algorithm, referred to as the Live Shill
Score (LSS), has been introduced to identify shill bidding while an auction is in
progress. Experimental analysis shows that the LSS algorithm can detect potential
shill bidders at the 80% duration mark of an online auction in most cases, which
is 20% quicker at detecting potential shill bidding than the existing published
proposals.
4. As real-world auction data contains a large number of auctions and participants,
the LSS algorithm has been extended to multiple auctions. The extended ver-
sion of real-time shill bidding detection algorithm has been referred to as
the multi-auction LSS. The algorithm has been implemented with a single seller.
Experimentation has been undertaken to determine how e ective the algorithm
is in identifying shill bidders across multiple auctions. However, some innocent
bidders were incorrectly classi ed as shill bidders when the algorithm considered
multiple auctions hosted by only a single seller. To avoid this misclassi cation,
the multi-auction LSS algorithm has been considered for multiple auctions con-
ducted by multiple sellers. Experimental results show that the algorithm is able
to accurately detect potential shill bidding across multiple auctions. Comparative
analysis shows that the multi-auction LSS with multiple sellers performs better
than the multi-auction LSS with a single seller and the LSS algorithm.
5. Detecting potential shill bidders becomes more di cult when a seller involves two
or more bidders and forms a collusive group to commit shill bidding in his/her own
auction(s). The reason is colluding shill bidders can distribute the work evenly
among each other to collectively reduce their chances of being detected. An o ine
approach to detect colluding shill bidders in online auctions based on machine
learning techniques has been proposed. The solution is referred to as the Collusive
Shill Bidding Detection (CSBD). The CSBD algorithm has been implemented and
applied on both simulated and commercial auction datasets. Experimental results
show that the CSBD algorithm can detect potential colluding shill bidders. Later,
the algorithm has been extended to a real-time approach, referred to as the real-
time CSBD algorithm. The real-time CSBD has been implemented and applied
on simulated and commercial auction datasets. Experimental analysis shows that
the algorithm is able to highlight potential colluding shill bidders in real-time.
6. Shill bidding detection becomes more complicated when a seller registers multiple
fake accounts and engages shill bidders in the auctions operated by those fake seller
accounts. Such behaviour is referred to as multiple seller collusive shill bidding,
where a seller can distribute the risk between the colluding sellers and reduce their
chance of identifying any particular seller (i.e., a shill bidder). There is no lit-
erature available on the detection of multiple seller collusive shill bidding
in real-time. A basic real-time detection algorithm using social network analy-
sis (SNA) has been proposed for identifying multiple seller collusive shill bidding
while an auction is in progress. The algorithm has been referred to as the Multi-
ple Seller Collusive Shill Bidding Detection (MSCSBD). The algorithm has been implemented and applied on synthetically generated auction dataset. Experimen-
tal results show that the algorithm behaves reasonably and can identify potential
colluding sellers who engage in shill bidding while an auction is in progress.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Info & Comm Tech
Science, Environment, Engineering and Technology
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Tang, Ya. "An empirical study of mobile auction adoption amongst online auction users in Hong Kong /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?ISMT%202006%20TANG.
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Wolf, James Richard. "Friction and trust in online markets." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1149085485.
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Yang, Boye. "Online auction price prediction a Bayesian updating framework based on the feedback history /." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43085830.
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Wong, Adam Ka Lok. "Factors affecting the adoption of online auctions by internet users in Hong Kong." Thesis, Heriot-Watt University, 2014. http://hdl.handle.net/10399/2733.
Full textAbstract:
This is an exploratory empirical study with the aim to identify the factors that affect the adoption of online auctions by Internet users in Hong Kong. The frameworks used were the TAM (Technology Acceptance Model), TCE (Transaction Cost Economics) and SERVQUAL (Service Quality). It was found that the dimensions that affected the customer’s perceived value of the online auction are benefits, costs, risks and service quality. Data was collected from four pilot focus groups, one online survey and a final focus group. The subjects in the focus groups were 21 undergraduates, whereas the subjects in the online survey were 152 internet users. The results of the pilot focus groups guided the design of the online survey. The results of the survey was analysed using the Kruskal-Wallis test. The final focus group was used to seek explanations to some issues arose from the online survey. It was found that the factors in the benefit dimension were liquidity, enjoyment, and price transparency. The factors in the cost dimension were time, effort, service charge and reputation of the user. The factor in the risk dimension was financial risk. The factors in the service quality dimension were efficiency and system availability. The final focus group revealed that the auctioneer’s role in policing the auction web site was important. For differences among the subjects, it was also found that the adult users consider their reputation in auction website, young adults are worried about financial risks, and female users are more concerned about financial risks than male users. The implications of these differences are discussed. The main academic contribution was the development of a questionnaire and a model which can be used in further research about other forms of auction.
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Ayara, Modupe. "Using evolutionary computation to find robust strategies for software agents in online auctions /." Leeds, 2001. http://www.leeds.ac.uk/library/counter2/compstmsc/20002001/ayara.ps.
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Despotakis, Stylianos. "Expertise, Attribution, and Ad Blocking in the World of Online Marketing." Research Showcase @ CMU, 2018. http://repository.cmu.edu/dissertations/1201.
Full textAbstract:
In this dissertation, we model and provide insights to some of the main challenges the world of online marketing currently faces. In the first chapter, we study the role of information asymmetry introduced by the presence of experts in online marketplaces and how it affects the strategic decisions of different parties in these markets. In the second chapter, we study the attribution problem in online advertising and examine optimal ways for advertisers to allocate their marketing budget across channels. In the third chapter, we explore the effects of modern ad blockers on users and online platforms. In the first chapter, we examine the effect of the presence of expert buyers on other buyers, the platform, and the sellers in online markets. We model buyer expertise as the ability to accurately predict the quality, or condition, of an item, modeled as its common value. We show that nonexperts may bid more aggressively, even above their expected valuation, to compensate for their lack of information. As a consequence, we obtain two interesting implications. First, auctions with a “hard close” may generate higher revenue than those with a “soft close”. Second, contrary to the linkage principle, an auction platform may obtain a higher revenue by hiding the item’s common-value information from the buyers. We also consider markets where both auctions and posted prices are available and show that the presence of experts allows the sellers of high quality items to signal their quality by choosing to sell via auctions. In the second chapter, we study the problem of attributing credit for customer acquisition to different components of a digital marketing campaign using an analytical model. We investigate attribution contracts through which an advertiser tries to incentivize two publishers that affect customer acquisition. We situate such contracts in a two-stage marketing funnel, where the publishers should coordinate their efforts to drive conversions. First, we analyze the popular class of multi-touch contracts where the principal splits the attribution among publishers using fixed weights depending on their position. Our first result shows the following counterintuitive property of optimal multi-touch contracts: higher credit is given to the portion of the funnel where the existing baseline conversion rate is higher. Next, we show that social welfare maximizing contracts can sometimes have even higher conversion rate than optimal multi-touch contracts, highlighting a prisoners’ dilemma effect in the equilibrium for the multi-touch contract. While multi-touch attribution is not globally optimal, there are linear contracts that “coordinate the funnel” to achieve optimal revenue. However, such optimal-revenue contracts require knowledge of the baseline conversion rates by the principal. When this information is not available, we propose a new class of ‘reinforcement’ contracts and show that for a large range of model parameters these contracts yield better revenue than multi-touch. In the third chapter, we study the effects of ad blockers in online advertising. While online advertising is the lifeline of many internet content platforms, the usage of ad blockers has surged in recent years presenting a challenge to platforms dependent on ad revenue. In this chapter, using a simple analytical model with two competing platforms, we show that the presence of ad blockers can actually benefit platforms. In particular, there are conditions under which the optimal equilibrium strategy for the platforms is to allow the use of ad blockers (rather than using an adblock wall, or charging a fee for viewing ad-free content). The key insight is that allowing ad blockers serves to differentiate platform users based on their disutility to viewing ads. This allows platforms to increase their ad intensity on those that do not use the ad blockers and achieve higher returns than in a world without ad blockers. We show robustness of these results when we allow a larger combination of platform strategies, as well as by explaining how ad whitelisting schemes offered by modern ad blockers can add value. Our study provides general guidelines for what strategy a platform should follow based on the heterogeneity in the ad sensitivity of their user base.
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Mousavi, Mohammad. "Managing Customer Complaints in Online Auction Markets." ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7563.
Full textAbstract:
The purpose of this multiple case study was to explore strategies managers in the online auction industry used to manage customer complaints to improve customer satisfaction. The targeted population consisted of 4 managers of online auction companies in the southwestern region of the United States. The conceptual framework for the study was Argyris and Sch�n's double-loop learning theory. Data were collected via semistructured interviews with business managers, observation of company operations and behaviors, review of documentation, and member-checking activities. Data analysis consisted of text interpretation of data and notes using coding techniques. Data analysis resulted in 5 themes: business orientation, customer purview, complaints handling, coping strategies, and learning abilities. The implications of this study for positive social change include facilitating the growth of online markets and increasing lower-cost purchasing opportunities for consumers with limited access to conventional marketplaces.
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Jeon, Sua. "The Effect of Consumer Shopping Motivations on Online Auction Behaviors: An Investigation of Searching, Bidding, Purchasing, and Selling." Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5366/.
Full textAbstract:
The purposes of the study were to: 1) identify the underlying dimensions of consumer shopping motivations and attitudes toward online auction behaviors; 2) examine the relationships between shopping motivations and online auction behaviors; and 3) examine the relationships between shopping attitudes and online auction behaviors. Students (N = 341) enrolled at the University of North Texas completed self-administered questionnaires measuring shopping motivations, attitudes, online auction behaviors, and demographic characteristics. Using multiple regression analyses to test the hypothesized relationships, shopping motivations and shopping attitudes were significantly related to online auction behaviors. Understanding the relationships is beneficial for companies that seek to retain customers and increase their sales through online auction.
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Yang, Boye, and 扬博野. "Online auction price prediction: a Bayesian updating framework based on the feedback history." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43085830.
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Abdul-Ghani, Eathar Mohammad. "Buyers' enduring involvement with online auctions a New Zealand perspective : a thesis submitted to Auckland University of Technology in partial fulfilment of the requirements for the degree of Master of Philosophy (MPhil), 2009 /." AUT University, 2009. http://hdl.handle.net/10292/820.
Full textAbstract:
Consumer-to-consumer (C2C) online auctions represent an important new marketplace from which consumers can access the goods they require, an alternative marketplace to bricks-and-mortar and online retail stores. Sellers are often ordinary consumers and the items on sale are often second-hand household items, although, modern C2C auction sites also accommodate small businesses selling unused products. Consumer behaviour in online C2C auctions is unlike consumer behaviour in bricks-and-mortar or online retail stores. While considerable research has been conducted into the dynamics of bidding in online C2C auctions little research has addressed the motives for consumers’ ongoing participation in this marketplace. The concept of consumer involvement may explain the amount of time and money consumers are spending in online C2C auctions and the frequency of their visits to auction sites. In the context of this thesis, involvement is defined as the long-term and enduring relevance, connection and relatedness of online auctions to a consumer’s life. The aim of this research is to explore the ways in which the consumer involvement construct offers an explanation for variation in buyers’ ongoing use of online auctions. The thesis also seeks to discover which consumer motives contribute to buyers’ enduring involvement with online auctions. TradeMe is New Zealand’s most popular online C2C auction site. In a country of just four million people, the TradeMe auction site has more than 2 million members and accounts for more than 50 per cent of Internet traffic originating from New Zealand websites. This study of buyers who use the TradeMe auction site, offers the opportunity to study online auction consumers in this unique context. Based on an extensive literature review, eighteen propositions were developed regarding buyer motives for enduring involvement with online C2C auctions. In-depth, semi-structured interviews were conducted with twenty TradeMe users, to test these propositions and to identify any further motives for enduring involvement with auctions that had not been revealed in the literature review. Interviews were audio-recorded and transcribed in full. NVivo8 qualitative data analysis software was used to code the interview transcripts. Thematic analysis reveals six themes representing buyer motives for enduring involvement with online auctions. The significant contribution of this thesis is to identify involvement as a useful construct for explaining consumer behaviour in online auctions. In addition to utilitarian and hedonic motives for involvement with online auctions, the interviews reveal that the buyers have a number of social and personal motives for involvement with online auctions. Analysis of the qualitative dataset also reveals a set of marketer activities which encourage ongoing use of the auction site, and a number of factors (anti-motives) which discourage use of the auction site. The research reveals the existence of an off-line community of auction users who value the social contact they experience with one another outside the auction site. Ongoing buyer-seller relationships are also shown to develop outside the auction site, prompted by an initial auction transaction. TradeMe users often express loyalty to the TradeMe website because they are proud of its New Zealand origins, feel secure in using a local auction website, believe they are supporting small New Zealand businesses by buying from TradeMe, and believe they are practicing sustainable consumption behaviour by purchasing second-hand goods. Future research should develop a multi-item, quantitative measure of buyers’ enduring involvement with online auctions and test the validity of this measure with further empirical data.
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Deb, Saumyanil. "An empirical analysis of seller's decision about the revelation of bidder information in online auctions /." Full text available from ProQuest UM Digital Dissertations, 2007. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1404347201&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1219255975&clientId=22256.
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Wolf, James Richard Jr. "Friction and trust in online markets." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1149085485.
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Mehta, Aranyak. "Algorithmic Game Theory." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7220.
Full textAbstract:
The interaction of theoretical computer science with game theory and
economics has resulted in the emergence of two very interesting
research directions. First, it has provided a new model for algorithm
design, which is to optimize in the presence of strategic
behavior. Second, it has prompted us to consider the computational
aspects of various solution concepts from game theory, economics and
auction design which have traditionally been considered mainly in a
non-constructive manner. In this thesis we present progress along both
these directions. We first consider optimization problems that arise
in the design of combinatorial auctions. We provide an online
algorithm in the important case of budget-bounded utilities. This
model is motivated by the recent development of the business of online
auctions of search engine advertisements. Our algorithm achieves a
factor of $1-1/e$, via a new linear programming based technique to
determine optimal tradeoffs between bids and budgets. We also provide
lower bounds in terms of hardness of approximation in more general
submodular settings, via a PCP-based reduction. Second, we consider
truth-revelation in auctions, and provide an equivalence theorem
between two notions of strategy-proofness in randomized auctions of
digital goods. Last, we consider the problem of computing an
approximate Nash equilibrium in multi-player general-sum games, for
which we provide the first subexponential time algorithm.
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Oh, Se-Kyoung. "Procurement Mechanisms in the Presence of Learing by Doing." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7525.
Full textAbstract:
In markets where suppliers experience learning by doing over time or, more generally, economies of scale in production, buyers are auctioning off longer-term contracts with an eroding price policy. Under an eroding price contract, the buyer initially competitively awards production to the lowest-bid supplier via an auction. Before
the auction takes place, the buyer makes it clear to the suppliers that, if chosen, a sequence of price reductions will be mandatory in
subsequent periods.
In this thesis, we mainly study the design of the optimal eroding price contract in a two period setting under three different model settings : (1) Every supplier faces a new cost in each period (NLI model), (2) The supplier who wins the auction in the first period locks-in his cost for the future, and the buyer makes the future payment based on the winning supplier's current bid (LI1), and (3) The supplier who wins the auction in the first period locks-in his
cost for the future, and the buyer makes the future payment based on the winning supplier's actual cost (LI1). Under NLI setting, the magnitude of the cost reduction due to learning by doing is common knowledge, while the magnitude is uncertain under LI1 and LI2
settings. We also study the optimal reserve prices in sequential independent auctions under NLI setting.
We go on to compare the performance of the eroding price policy against sequential independent auctions (without or with the optimal
reserve prices) under the above model settings. Via analytical and numerical comparisons, we find that even in the presence of learning
by doing/economies of scale in production, a buyer is often better off running sequential auctions with a reserve price, rather than
limiting competition and contracting with a single supplier in the hopes of extracting a better future price.
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Teytelboym, Alexander. "Essays on networks and market design." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:03323fa7-a2a1-425f-862e-e788fa4e0954.
Full textAbstract:
This thesis comprises four essays in the economics of networks and market design. The common thread in all these essays is the presence of complementarities or externalities. Chapter 2 presents a unified model of networks and matching markets. We build on a contribution by Pycia (2012). We show that strong pairwise alignment of agents’ preferences is a necessary and sufficient condition for the existence of strongly stable networks and strongly stable allocations in multilateral matching markets with finite contracts. Strongly stable networks are not necessarily efficient. Although we use a demanding stability concept, strong pairwise alignment allows for complementarities and externalities. In Chapter 3, we generalise the gross substitutes and complements condition introduced by Sun and Yang (2006). Our new condition guarantees the existence of competitive equilibrium in economies with indivisible goods. Competitive equilibrium can be found using an extension of the double-track adjustment process (Sun and Yang, 2009). In this chapter, we also study contract networks (Ostrovsky, 2008). We show that chain-stable contract allocations can exist even in cyclical contractual networks, such as electricity markets, as long as they are appropriately segmented. In Chapter 4, we run a series of experiments to compare the performance of four auctions – first-price, Vickrey, Vickrey-Nearest Rule (Day and Cramton, 2008), and Reference Rule (Erdil and Klemperer, 2010). In our setting, there are two items and three bidders. Two local bidders want an item each, but the global bidder wants both items. We introduce various exposure and package-bidding treatments. We find that the first-price auction always revenue-dominates all the other auctions without any loss in efficiency, strengthening the results of Marszalec (2011). Exposure affects global bidders only in the first-price auction. In other auctions, global bidders often do not take into account the effect of their own bids on their payments. We find no evidence of threshold effects. Finally, in Chapter 5, we develop a new model of online social network formation. In this model, agents belong to many overlapping social groups. We derive analytical solutions for the macroscopic properties of the network, such as the degree distribution. We study the dynamics of homophily – the tendency of individuals to associate with those similar to themselves. We calibrate our model to Facebook data from ten American colleges.
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Bertsimas, Dimitris J., Jeff Hawkins, and Georgia Perakis. "Optimal Bidding in Online Auctions." 2002. http://hdl.handle.net/1721.1/4006.
Full textAbstract:
Online auctions are arguably one of the most important and distinctly new applications of the internet. The predominant player in online auctions, eBay, has over 18.9 milllion users, and it was the host of over $5 billion worth of goods sold in the year 2000. Using methods from approximate dynamic programming and integer programming, we design algorithms for optimally bidding for a single item online auction, and simultaneous or overlapping multiple online auctions. We report computational evidence using data from eBay's web site from 1772 completed auctions for personal digital assistants and from 4208 completed auctions for stamp collections that show that (a) the optimal dynamic strategy outperforms simple but widely used static heuristic rules for a single auction, and (b) a new approach combining the value functions of single auctions found by dynamic programming using an integer programming framework produces high quality solutions fast and reliably.Singapore-MIT Alliance (SMA)
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Huang, Yao-Min, and 黃耀民. "Endowment Effect in Online Auctions." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/45423829463616157797.
Full textAbstract:
碩士國立臺灣大學
經濟學研究所
99
One bidder submitting multiple bids is a prevalent phenomenon in online auctions. Some literatures argue that endowment effect may result in over-bidding. Endowment effect describes the fact that people often demand more to give up an item than they will pay to acquire it. As the leading time becomes longer, bidders may develop a psychological ownership for the object auctioned. Endowment effect makes people submit another higher bid to avoid losing “their” item. We use the data of Yahoo! Auction Taiwan to examine whether the positive relationship between the time of being highest bidder and the probability of rebidding exists. However, we find that leading time may have other effects on bidder behavior. First, a very short leading time implies that the auction is very competitive. This situation may make bidders more eager to win the auction, so the possibility of rebidding increases. Second, if the values of the object to bidders are interdependent, the leading time is informative. A bidder may infer the previous bid he submitted is too high if he led for a long period of time. These effects will make the probability of rebidding decrease with leading time. Since the perception of owning an item needs time to develop, we suggest that when the bidders lead for a relatively short period of time, the probability of rebidding and the leading time are negatively correlated. After the leading time is so long that the bidder thinks he is the owner of the object, the probability of rebidding starts to increase with leading time. The regression results in this thesis support our hypothesis.
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Huang, Yi-Ping, and 黃怡萍. "A Study on the Influence of Auction Duration over the Online Auctions." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/62170803313079848158.
Full textAbstract:
碩士東吳大學
企業管理學系
92
The application of Internet makes flourished the electronic markets and online auction is the best example in this trend. Online auction has become popular in recent years and it has crucial influence on electronic marketplace. There are many differences between online auctions and traditional auctions. The most important one is that online auction has a fixed bidding period( so called: auction duration) and it is extremely different from traditional “going、going、gone” bidding procedures. This thesis will focus on the study of auction duration. EBay, the largest online auction houses in the world, was the study subject and the samples were downloaded from eBay. The bid histories on eBay were used for the analyses. The relative time form and the absolute time form were applied to examine the influence of auction duration on bid numbers and on price curves. The multiple regressions were the main research method. The result showed that the longer the auction duration is, the more bidders would bid early in the auctions. In this way, the phenomenon of late bidding would be eliminated and the end price is more reliable in the auctions. Therefore, the length of auction duration would have influence on the bidding behaviors directly.
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Zhang, Yu. "Online Auctions: Theoretical and Empirical Investigations." 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8516.
Full textAbstract:
This dissertation, which consists of three essays, studies online auctions both
theoretically and empirically.
The first essay studies a special online auction format used by eBay, “Buy-It-
Now” (BIN) auctions, in which bidders are allowed to buy the item at a fixed BIN
price set by the seller and end the auction immediately. I construct a two-stage
model in which the BIN price is only available to one group of bidders. I find that
bidders cutoff is lower in this model, which means, bidders are more likely to accept
the BIN option, compared with the models assuming all bidders are offered the BIN.
The results explain the high frequency of bidders accepting BIN price, and may also
help explain the popularity of temporary BIN auctions in online auction sites, such
as eBay, where BIN option is only offered to early bidders.
In the second essay, I study how bidders’ risk attitude and time preference affect
their behavior in Buy-It-Now auctions. I consider two cases, when both bidders enter
the auction at the same time (homogenous bidders) thus BIN option is offered to both
of them, and when two bidders enter the auction at two different stages (heterogenous
bidders) thus the BIN option is only offered to the early bidder. Bidders’ optimal
strategies are derived explicitly in both cases. In particular, given bidders’ risk attitude and time preference, the cutoff valuation, such that a bidder will accept BIN if
his valuation is higher than the cutoff valuation and reject it otherwise, is calculated.
I find that the cutoff valuation in the case of heterogenous bidders is lower than that
in the case of homogenous bidders.
The third essay focuses on the empirical modeling of the price processes of online
auctions. I generalize the monotone series estimator to model the pooled price
processes. Then I apply the model and the estimator to eBay auction data of a palm
PDA. The results are shown to capture closely the overall pattern of observed price
dynamics. In particular, early bidding, mid-auction draught, and sniping are well
approximated by the estimated price curve.
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Chang, Wen-Hsi, and 張文熙. "Effective Fraud Detection in Online Auctions." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/36435336490875464863.
Full textAbstract:
博士淡江大學
管理科學學系博士班
101
In recent years, online auction has become one of the most successful business models; however, the tremendous profit also appeals to many fraudsters. Schemed fraudsters camouflage their malicious intent to distract customers for profit, seriously threatening online auction security. This dissertation aims to develop a set of methods for constructing an effective early fraud detection system. This research proposes various detection methods taking detection cost into account to enhance the practicality of such a system, including the following: (1) To satisfy the need of early fraud detection, a phased profiling approach partitions the transaction histories of traders before detection model construction. The latent behavior of uncovered fraudsters can be extracted from these segmented transaction histories presenting different periods of lifespan that is helpful in observing fraudulent behavior fluctuation. (2) To address the diversity of latent behavior, a hybrid phased modeling method increases the detection accuracy for latent fraudsters. This method extracts features from different phases of the latency period to construct models for enhancing the capability of early fraud detection. To further improve accuracy, a two-stage detection procedure uses various detection models to carefully examine the behavior of a suspicious account. (3) To reduce detection costs, a modified wrapper approach is used to select a concise set of measured attributes, which is then used to construct the model. In addition, a complement phased modeling method increases the accuracy while facilitating the data downloading from the auction site, providing a cost-effective detection procedure. (4) To analyze the evolution of fraudulent behavior, clustering methods incorporated with phased profiling are used to classify the types of fraudsters. This analysis helps to parse fraudulent behavior with greater granularity and resolution. To test the effectiveness of the methods we proposed, real transaction records were collected from Yahoo!Taiwan. The proposed methods not only improve the accuracy of fraud detection but can also identify latent fraudsters, a necessary requirement for early detection. The results show that these methods improve the practicality of fraud detection system, allowing online auction participants and the trading environment to be secured in a cost-effective way.
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Trevathan, Jarrod. "Privacy and security in online auctions." Thesis, 2007. https://researchonline.jcu.edu.au/1788/1/01front.pdf.
Full textAbstract:
Buying and selling online is inherently insecure. Misuse of an individual's personal information is now the leading concern among those who engage in e-commerce. This thesis examines privacy and security
issues in online auctions. Various auction fraud issues are investigated, and several novel counter measures
proposed. An online auction server was constructed to aid in developing these security measures. This
allowed investigation and testing in a controlled environment. The research results include:
1. A complete model for conducting secure and anonymous online auctions;
2. A method for detecting a fraudulent bidding practice referred to as shill bidding;
3. Autonomous bidding agents which bid maliciously. (Used to test the ability of the proposed security
mechanisms.);
4. A complete model for conducting secure and anonymous online share trading; and
5. Several alternate proposals for auction clearing algorithms.
The proposed security mechanisms have been implemented on the online auction server. Results are
given as simulated and practical tests. In addition, the auction server's software design is documented.
Many of the techniques discussed in this thesis can be readily applied to commercial online auctions.
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Shen, Chung-Chi, and 沈宗奇. "An Investigation into the Auction Strategy and Bidder’s Bidding Behavior in Online Auctions:." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/33550056691743306032.
Full text
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Sehwail, Loay. "Implementing business-to-business online reverse auctions." 2006. http://digital.library.okstate.edu/etd/umi-okstate-1888.pdf.
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Huang, Ching-Wei, and 黃菁瑋. "Applying Trust Mechanisms for C2C Online Auctions." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/63457800376912347778.
Full textAbstract:
碩士國立中正大學
資訊管理學系
88
With the phenomenal growth of commercial applications on Internet, more and more security breaches occurred. EC lacks security and reliability arising from the issues of a “complete trustworthy relationship” among the trading partners. In online transactions, businesses can use agreements, reputations or social contracts to establish confidences of consumers. But in C-to-C transactions, direct trusts are hard to develop in the trading relationships due to anonymous and non-face-to-face interaction between trading partners in Internet. In the integrated model of trust in EC (Kini & Choobineh,1998), trust in an on-line system is a function of the person, the on-line system, the task, and the information environment. In this study, We conduct field experiment in a C-to-C auction website. Trading partner trust and service satisfaction are used as our measurement for testing the effects of the individual’s tendency to trust and trust mechanism in the C-to-C trading relationship. An empirical study was conducted with a 2*3 factorial design in the experiment (low or high tendency to trust vs. no trust mechanism, reputation brokering mechanism, or trusted third party mechanism). The main findings of this study are: (1) The individual’s tendency to trust is a significant factor in online trading relationship trust. (2) By applying trust mechanisms, it indeed enhances consumer’s trading partner trust and services satisfaction. (3) There are significant differences in tangibility, assurance and empathy of satisfactions among various trust mechanisms. (4) Consumers with high tendency to trust have lower satisfactions at services than consumers with low tendency to trust. (5) The impacts of trust mechanisms on trading trust and satisfaction are not affected by the individual’s tendency to trust. (6) The effects of the individual’s tendency to trust and trust mechanism on trading trust and satisfaction are not moderated by the individual’s computer self efficacy.
49
Wu, Chia-Hua, and 吳佳樺. "Detecting fraud in Taiwan Yahoo! online auctions." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/k3au94.
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碩士國立交通大學
資訊學院碩士在職專班數位圖書資訊組
97
The rapid advancement of the Internet has led to the development of many innovative ideas. These innovations, in turn, have changed the ways in which human beings interact with each other. Online auction is one such example. It provides buyers and sellers with a platform for quick exchange of information and trading opportunities; unfortunately, many fraudulent scams have also arisen out of these Internet auctions. This thesis attempts to detect frauds on the Yahoo! Auctions platform by using the data classification technique in Data Mining. Transaction information was firstly gathered from the auction platform. The attributes of a transaction are extracted for analysis, which include item number, seller ID, start and end time for bidding, bidding time remaining, item location, customer review, delivery fee and method, fraud assessment, current bidding price, number of bids, item quantity, credit card authentication, direct payment option, item condition, self-collect option, in-person transaction option, mobile-phone verification, and recent feedback ratings. Attributes with a high-correlation to frauds were identified and further analyzed via data classification. The aim is to provide a better understanding on how online auction frauds are carried out. This thesis adopted a scientific method to identify common fraudulent practices in Internet auctions. It achieved an Accuracy level of up to 97.67% and an F-Measure of up to 92.77%. From the data sets collected in the study, the following rules with respect to the attributes of a transaction have a prominent correlation with auction frauds. In addition, the more rules that are satisfied, the more possibility that a fraud may occur. The bidding time is less than five days (risk level was even higher in auctions with bidding time less than two days). The item is located in in Taitung County, Hualien County, Hsinchu County, Pingtung County, Tainan County, Kaohsiung County, Keelung City, Chiayi County, Miaoli County, Kaohsiung City, Taichung County, Taoyuan County The transaction permits in-person transaction. The transaction permits self-collection but not cash against delivery. The item condition was classified as "new" or "used for one to three months". The seller has passed the credit card authentication. The item price is between TWD3000 and 20,000. The auctions fraud normally occur in the second half of the month
50
Gupta, Shobhit, and Jérémie Gallien. "Temporary and Permanent Buyout Prices in Online Auctions." 2004. http://hdl.handle.net/1721.1/7468.
Full textAbstract:
Increasingly used in online auctions, buyout prices allow bidders to instantly purchase the item listed. We distinguish two types: a temporary buyout option disappears if a bid above the reserve price is made; a permanent one remains throughout the auction or until it is exercised. In a model featuring time-sensitive bidders with uniform valuations and Poisson arrivals but endogenous bidding times, we focus on finding temporary and permanent buyout prices maximizing the seller's discounted revenue, and examine the relative benefit of using each type of option in various environments. We characterize equilibrium bidder strategies in both cases and then solve the problem of maximizing seller's utility by simulation. Our numerical experiments suggest that buyout options may significantly increase a seller’s revenue. Additionally, while a temporary buyout option promotes early bidding, a permanent option gives an incentive to the bidders to bid late, thus leading to concentrated bids near the end of the auction.Singapore-MIT Alliance (SMA)