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Uma infra-estrutura para agentes arrematantes em múltiplos leilões simultâneos.; An infrastructure for bidder agents in multiple simultaneous auctions.

Castro, Paulo André Lima de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 28/08/2003 PT
Relevância na Pesquisa
37.4%
Em meio a centenas de sítios de leilões na Internet, observa-se que alguns oferecem serviços de agentes para procurar, monitorar e/ou oferecer lances nos leilões. A maior parte dos sistemas baseados em agentes não oferece apoio ao acompanhamento e à submissão de lances em vários leilões simultâneos. Estas atividades são especialmente importantes, pois o fato de participar simultaneamente em vários leilões eleva a probabilidade de conseguir melhores resultados econômicos, devido à possibilidade de encontrar mercados mais vantajosos. Contudo, à medida que cresce o número de leilões simultâneos, torna-se inviável para um ser humano monitorá-los e oferecer lances. Neste contexto, o uso de agentes pode ser extremamente interessante. Neste trabalho, propõe-se uma infra-estrutura para facilitar a construção de agentes arrematantes para operarem no eMediator (Sandholm, 2000) em múltiplos leilões. Com tal infra-estrutura computacional batizada de sistema AAS (Auction Agent System), a implementação de novas estratégias em agentes arrematantes será facilitada. Desta forma, este trabalho contribui para o avanço na pesquisa de novas estratégias de atuação de agentes arrematantes para o caso de múltiplos leilões simultâneos.; Among hundred of auction sites in the internet...

Renda de informação nos leilões de exploração de petróleo no Brasil: uma estimação não-paramétrica com assimetria entre os agentes; Information rent in the exploration auctions of oil in Brazil: a non-parametric estimation assuming asymmetry between the participants

Brasil, Eric Universo Rodrigues
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/11/2009 PT
Relevância na Pesquisa
37.26%
Esta dissertação tem como objetivo estimar a renda de informação apropriada pelos vencedores dos leilões para exploração e produção de petróleo e gás natural no Brasil. Assume-se um modelo estrutural de leilão de valor privado independente. Foram estimadas as distribuições dos lances e dos valores privados dos lançadores de forma não-paramétrica, assumindo assimetria entre os participantes (Petrobras+OGX versus outros). Para isso, explorou-se um banco de dados construído a partir de informações de todos os leilões realizados entre 1999 e 2008. Tal estudo é relevante por tentar avaliar o sucesso do governo brasileiro e das empresas licitantes nestes leilões, principalmente diante da discussão do novo marco regulatório do pré-sal. Os resultados sugerem que a Petrobras e a OGX obtiveram rendas de informação significativamente maiores que as demais concorrentes. Tais rendas variam entre 14% e 63%, dependendo do número de competidores e de seu tipo. De maneira geral, o governo tende a extrair maior parte do preço de reserva do vencedor do leilão quando este não é a Petrobras ou a OGX e quanto maior for o número de concorrentes.; This dissertation aims to estimate the information rent grabbed by the winners of auctions for exploration and production of oil and natural gas in Brazil. It assumes a structural model of independent private values for the auctions. We estimated non-parametrically both the distributions of bids and the distribution of private values from bidders...

Generic-branded drug competition and the price for pharmaceuticals in procurement auctions

Arvate, Paulo; Barbosa, Klenio de Souza; Gambardella, Dante
Fonte: Fundação Getúlio Vargas Publicador: Fundação Getúlio Vargas
Relevância na Pesquisa
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This paper studies the effects of generic drug’s entry on bidding behavior of drug suppliers in procurement auctions for pharmaceuticals, and the consequences on procurer’s price paid for drugs. Using an unique data set on procurement auctions for off-patent drugs organized by Brazilian public bodies, we surprisingly find no statistically difference between bids and prices paid for generic and branded drugs. On the other hand, some branded drug suppliers leave auctions in which there exists a supplier of generics, whereas the remaining ones lower their bidding price. These findings explain why we find that the presence of any supplier of generic drugs in a procurement auction reduces the price paid for pharmaceuticals by 7 percent. To overcome potential estimation bias due to generic’s entry endogeneity, we exploit variation in the number of days between drug’s patent expiration date and the tendering session. The two-stage estimations document the same pattern as the generalized least square estimations find. This evidence indicates that generic competition affects branded supplier’s behavior in public procurement auctions differently from other markets.

Affiliation, equilibrium existence and the revenue ranking of auctions

Castro, Luciano Irineu de
Fonte: Escola de Pós-Graduação em Economia da FGV Publicador: Escola de Pós-Graduação em Economia da FGV
Tipo: Relatório
EN_US
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We consider private value auctions where bidders’ types are dependent, a case usually treated by assuming affiliation. We show that affiliation is a restrictive assumption in three senses: topological, measure-theoretic and statistical (affiliation is a very restrictive characterization of positive dependence). We also show that affiliation’s main implications do not generalize for alternative definitions of positive dependence. From this, we propose new approaches to the problems of pure strategy equilibrium existence in first-price auctions (PSEE) and the characterization of the revenue ranking of auctions. For equilibrium existence, we slightly restrict the set of distributions considered, without loss of economic generality, and offer a complete characterization of PSEE. For revenue ranking, we obtain a characterization of the expected revenue differences between second and first price auctions with general dependence of types.

Um agente para leilões eletronicos simultaneos heterogeneos com bens inter-relacionados; An agent for electronic simultaneous heterogeneous auctions with inter-related goods

Cynthia Samara de Medeiros Gonzaga
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 11/05/2006 PT
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Agentes computacionais têm um papel importante no comércio eletrônico, pois permitem um melhor aproveitamento de negociações e aumentam o grau de automação do mercado eletrônico. Agentes podem interagir entre si para atingir seus objetivos. Leilões fornecem mecanismos simples de interação e negociação entre agentes e, com o advento da Internet, estão se tomando um veículo eficaz para a realização de negociações eletrônicas intermediadas por agentes. Destaca-se nesse contexto o desenvolvimento de agentes para atuar em leilões eletrônicos simultâneos heterogêneos com bens inter-relacionados. Participar de múltiplos leilões simultaneamente traz a vantagem de permitir, por exemplo, que um agente possa monitorar preços de vários leilões e realizar o negócio naquele que se mostrar mais lucrativo. Além disso, muitas vezes a compra de bens individuais pode não fazer sentido. É o caso, por exemplo, de passagens aéreas e diárias de hotel em agências de viagem; a compra de um bem só se justifica diante da presença do outro. Com o intuito de promover e encorajar pesquisas na área de agentes atuando em leilões eletrônicos simultâneos heterogêneos com bens interrelacionados criou-se uma competição, o Trading Agent Competition-Classic (TAC-Classic). O TACClassic simula uma agência de viagem onde os agentes (participantes da competição) têm o objetivo de propor pacotes de viagem. Os bens são negociados em leilões simultâneos heterogêneos. Esta dissertação versa sobre o agente e-Agent...

Metodologia e simulação de leilão simultâneo-combinatório para novos empreendimentos de geração de energia elétrica; Methodology and simulation of simultaneous-combinatorial auctions for new power plants

Elisa Bastos Silva
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 15/02/2011 PT
Relevância na Pesquisa
37.45%
Os mecanismos de comercialização de energia elétrica foram modificados pelo Governo por meio do novo modelo do setor elétrico instituído em 2004. Esse procedimento foi definido, elegendo-se os leilões como forma de licitação para o ambiente de contratação regulada, objetivando minimizar os preços de venda (aproximando-os do custo de produção) e introduzir a competição de mercado. O mecanismo de leilões, no âmbito do setor elétrico, foi adotado por diversos países, que nem sempre obtiveram níveis elevados de. Entretanto, apesar das experiências de insucesso, verifica-se a necessidade de se comercializar energia elétrica através de contratos de longo prazo; logo a formatação dos leilões deve prever diversos aspectos com vista a evitar tais insucessos. Por isso, para o setor elétrico brasileiro, anualmente, são descritas pelo MME uma série de diretrizes em que constam os procedimentos para habilitação técnica, prazos e sistemática adotada para esses leilões. Em esfera nacional, os leilões são classificados como: leilão de linha de transmissão, leilão de energia existente, leilão de energia de ajuste, leilões de reserva e leilão de energia nova. Os leilões de novos empreendimentos tendem à expansão da oferta; são constituídos por aqueles que não sejam detentores de concessão...

Strong Activity Rules for Iterative Combinatorial Auctions

Harsha, Pavithra; Barnhart, Cynthia; Parkes, David C.; Zhang, Haoqi
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
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Activity rules have emerged in recent years as an important aspect of practical auction design. The role of an activity rule in an iterative auction is to suppress strategic behavior by bidders and promote simple, continual, meaningful bidding and thus, price discovery. These rules find application in the design of iterative combinatorial auctions for real world scenarios, for example in spectrum auctions, in airline landing slot auctions, and in procurement auctions. We introduce the notion of strong activity rules, which allow simple, consistent bidding strategies while precluding all behaviors that cannot be rationalized in this way. We design such a rule for auctions with budget-constrained bidders, i.e., bidders with valuations for resources that are greater than their ability to pay. Such bidders are of practical importance in many market environments, and hindered from bidding in a simple and consistent way by the commonly used revealed-preference activity rule, which is too strong in such an environment. We consider issues of complexity, and provide two useful forms of information feedback to guide bidders in meeting strong activity rules. As a special case, we derive a strong activity rule for non-budget-constrained bidders. The ultimate choice of activity rule must depend...

Ascending Price Vickrey Auctions for General Valuations

Mishra, Debasis; Parkes, David C.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
37.4%
Ascending price auctions involving a single price path and buyers paying their final bid price cannot achieve the Vickrey–Clarke–Groves (VCG) outcome in the combinatorial auctions setting. Using a notion called universal competitive equilibrium prices, shown to be necessary and sufficient to achieve the VCG outcome using ascending price auctions, we define a class of ascending price auctions in which buyers bid on a single price path. Truthful bidding by buyers is an ex post Nash equilibrium in such auctions. By giving discounts to buyers from the final price, the VCG outcome is achieved for general valuations.; Engineering and Applied Sciences

Hybrid Auctions II: Experimental Evidence

Dutra, Joisa C; Menezes, Flavio
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper Formato: 254224 bytes; application/pdf
EN_AU
Relevância na Pesquisa
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In this paper we report the results of an experiment designed to examine the properties of a hybrid auction - a Dutch-Vickrey auction, that combines a sealed bid first-price auction with a sealed bid second-price auction. This auction mechanism shares some important features with that used in the sale of the companies constituted through the partial division of the Telebras System - the government-owned Telecom holding in Brazil. We designed an experiment where individuals participate in a sequence of independent first-price auctions followed by a sequence of hybrid auctions. Several conclusions emerged from this experimental study. First, ex-post efficiency was achieved overwhelmingly by the hybrid auctions. Secondly, although overbidding (with respect to the risk-neutral Bayesian Nash equilibrium) was a regular feature of participants’ bidding behavior in the first-price auctions — as it is commonly reported in most experimental studies of first-price auctions, it was less frequent in the hybrid auctions. By calibrating the results to allow for risk-averse behavior we were able to account for a significant part of the overbidding. Finally, we compared the revenue generated by the hybrid auction with that generated by a standard first-price sealed bid auction and the results were ambiguous.; no

Consumer Panelist Behavior in Experimental Auctions: What Do We Learn from Their Bids?

Umberger, W.; Feuz, D.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Conference paper
Publicado em //2001 EN
Relevância na Pesquisa
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Experimental economics procedures such as laboratory experimental auctions are increasingly being used to measure consumers’ willingness-to-pay. A sealed-bid, fourth-price Vickrey-style auction was used to measure consumers’ willingness-to-pay for flavor in beef steaks. Two hundred and forty-eight consumers from Chicago and San Francisco participated in the experimental auctions. The data gathered from these experimental auctions was then used to examine individual demand or utility in an experimental, uniform-price auction; and to analyze market demand and market price in an experimental auction when supply is fixed but demand varies. The results indicated that certain demographic variables may increase the probability that a participant wins or loses an experimental auction. The market price was found to be a function of the number of participants in a panel, as well as consumers’ tastes and preferences. Changes in the market price of the auctions in the study appear to be more a function of the same factors that influence demand in the marketplace, rather than a wealth effect. Consumers in this research did appear to be expressing their true value for the auction product and the auction provided a valuable measure of consumers’ WTP for flavor.; Copyright 2001 by Wendy J. Umberger and Dillon M. Feuz.

Three essays on corruption and auctions

PAPIOTI, Katerina Chara
Fonte: Instituto Universitário Europeu Publicador: Instituto Universitário Europeu
Tipo: Tese de Doutorado Formato: application/pdf; digital
EN
Relevância na Pesquisa
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This thesis contributes to the understanding of corruption and auctions. It consists of three chapters focusing on diverse aspects of these two general topics as well as their combinations, from an applied microeconomic theory perspective: (i) the effects of corruption on bidding behaviour in all-pay auctions and the auctioneer’s decisions, (ii) the use of central bank bond auctions as tools to measure banks’ liquidity risk, and (iii) the persistence of corruption and corruption differences between similar economies. As discussed in recent bibliography, auctions performed by an intermediary between the seller of the good and buyers can be penetrable by corruption. Furthermore, corruption can enter auctions in different forms. In the first chapter of this thesis, entitled Corruption in All-Pay Auctions, we compare the effects of pure pecuniary corruption and favouritism on bidding behaviour and the auctioneer’s expected revenue, in the context of All-Pay Auctions, used to model lobbying, labour-market tournaments and competition for monopoly power. We provide conditions under which favouritism makes bidders more or less aggressive than in the benchmark model without corruption, and prove that bidders are always more aggressive when faced with a non favouritist corrupt auctioneer. In both cases...

Second-price common-value auctions under multidimensional uncertainty

Frutos, María Ángeles de; Pechlivanos, Lambros
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em /04/2006 ENG
Relevância na Pesquisa
37.32%
The literature has demonstrated that second-price common-value auctions are sensitive to the presence of asymmetries among bidders. In a two-bidder model, Bikhchandani [1988. Reputation in repeated second-price auctions. J. Econ. Theory 46, 97–119] has shown that if it is common knowledge that one bidder has a disadvantage compared to her opponent, that bidder (almost surely) never wins the auction. Employing a similar two-bidder model, this paper shows that this result does not carry over when one allows for two-sided uncertainty. In such case, in every equilibrium, the disadvantaged type bidder needs to win the auction with strictly positive probability. We then solve for the equilibria in two cases, one with two types and another with a continuum of types, and we show that they converge to the symmetric equilibria of the corresponding symmetric auctions. We thus reestablish a lost linkage in the analysis of common-value and almost-common-value auctions.

Modeling Electricity Auctions

Fabra, Natalia; Fehr, Nils-Henrik Von der; Harbord, David
Fonte: Elsevier Publicador: Elsevier
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article
Publicado em //2002 ENG
Relevância na Pesquisa
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The recent debates over discriminatory versus uniform-price auctions in the U.K. and elsewhere have revealed an incomplete understanding of the limitations of some popular auction models when applied to real-world electricity markets. This has led some regulatory authorities to prefer discriminatory auctions on the basis of reasoning from models which are not directly applicable to any existing electricity market. Vickrey auctions, although often recommended by economists, have also been ignored in these debates.

Designing Electricity Auctions

Fabra, Natalia; Fehr, Nils-Henrik Von der; Harbord, David
Fonte: RAND Corporation Publicador: RAND Corporation
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em //2006 ENG
Relevância na Pesquisa
37.32%
Motivated by the new auction format introduced in the England andWales electric- ity market, as well as the recent debate in California, we characterize bidding behavior and market outcomes in uniform and discriminatory electricity auctions. We ¯nd that uniform auctions result in higher average prices than discriminatory auctions, but the ranking in terms of productive e±ciency is ambiguous. The comparative e®ects of other market design features, such as the number of steps in suppliers' bid functions, the duration of bids and the elasticity of demand are also analysed. We also consider the relationship between market structure and market performance in the two auction formats. Finally, we clarify some methodological issues in the analysis of electricity auctions. In particular, we show that analogies with continuous share auctions are misplaced so long as ¯rms are restricted to a ¯nite number of bids.

Designing Electricity Auctions

Fabra, Natalia; Fehr, Nils-Henrik Von der; Harbord, David
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: Trabalho em Andamento Formato: application/pdf
Publicado em /02/2004 ENG
Relevância na Pesquisa
37.32%
Motivated by the new auction format introduced in the England andWales electric- ity market, as well as the recent debate in California, we characterize bidding behavior and market outcomes in uniform and discriminatory electricity auctions. We ¯nd that uniform auctions result in higher average prices than discriminatory auctions, but the ranking in terms of productive e±ciency is ambiguous. The comparative e®ects of other market design features, such as the number of steps in suppliers' bid functions, the duration of bids and the elasticity of demand are also analysed. We also consider the relationship between market structure and market performance in the two auction formats. Finally, we clarify some methodological issues in the analysis of electricity auctions. In particular, we show that analogies with continuous share auctions are misplaced so long as ¯rms are restricted to a ¯nite number of bids.

Promoting Renewable Energy through Auctions

Elizondo Azuela, Gabriela; Barroso, Luiz
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Journal Article; Publications & Research :: Brief; Publications & Research
ENGLISH; EN_US
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37.4%
This knowledge note singles out auctions as an important mechanism that has been implemented in a growing number of countries in recent decades. It features case studies of auctions designed to promote the generation of electricity from renewable sources in Brazil, China, and India. Auctions in various forms are being used to promote the generation of electricity from renewable sources. Properly structured auctions can avoid the disadvantages of feed-in tariffs and renewable purchase obligations. Moreover, they offer the best of both of these early mechanisms, providing stable revenue guarantees for investors while also avoiding the risk of overbuilding. They do this by determining both price and quantity in advance. Promoting renewable energy through auctions is important, because experience with the use of auctions can guide future efforts. Among the examples of the benefits to be obtained from generating electricity from renewable sources are (i) increasing countries' energy security by reducing their dependency on fossil fuel imports...

Detecting Collusion in Timber Auctions : An Application to Romania

Saphores, Jean-Daniel; Vincent, Jeffrey R.; Marochko, Valy
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
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Romania was one of the first transition countries in Europe to introduce auctions for allocating standing timber (stumpage) in public forests. In comparison with the former system in the country-administrative allocation at set prices-timber auctions offer several potential advantages: greater revenue generation for the government, a higher probability that tracts will be allocated to the firms that value them most highly, and stronger incentives for technological change within industry and efficiency gains in the public sector. Competition is the key to realizing these advantages. Unfortunately, collusion among bidders often limits competition in timber auctions, including in well-established market economies such as the United States. The result is that tracts sell below their fair market value, which undermines the advantages of auctions. This paper examines the Romanian auction system, with a focus on the use of econometric methods to detect collusion. It begins by describing the historical development of the system and the principal steps in the auction process. It then discusses the qualitative impacts of various economic and institutional factors, including collusion, on winning bids in different regions of the country. This discussion draws on information from a combination of sources...

Electricity Auctions : An Overview of Efficient Practices

Maurer, Luiz T. A.; Barroso, Luiz A.
Fonte: World Bank Publicador: World Bank
Tipo: Publications & Research :: Publication; Publications & Research :: Publication
ENGLISH
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This report assesses the potential of electricity contract auctions as a procurement option for the World Bank's client countries. It focuses on the role of auctions of electricity contracts designed to expand and retain existing generation capacity. It is not meant to be a 'how-to' manual. Rather, it highlights some major issues and options that need to be taken into account when a country considers moving towards competitive electricity procurement through the introduction of electricity auctions. Auctions have played an important role in the effort to match supply and demand. Ever since the 1990s, the use of long-term contract auctions to procure new generation capacity, notably from private sector suppliers, has garnered increased affection from investors, governments, and multilateral agencies in general, as a means to achieve a competitive and transparent procurement process while providing certainty of supply for the medium to long term. However, the liberalization of electricity markets and the move from single-buyer procurement models increased the nature of the challenge facing system planners in their efforts to ensure an adequate and secure supply of electricity in the future at the best price. While auctions as general propositions are a means to match supply with demand in a cost-effective manner...

Bidders’ Behaviour and Theory of Share Auctions with Applications to the Colombian Primary Bond Market

Cardozo, Pamela
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 608284 bytes; application/pdf
EN; EN
Relevância na Pesquisa
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Although most governments sell their bonds through a share auction, little is known about behaviour of bidders in these auctions. This thesis analyzes the literature on government securities auctions, focusing primarily on structural empirical estimation. Additionally, it examines bidders behaviour in Colombian government bond auctions during 2007, including the additional sale done after the auction. The thesis summarizes the different structural methodologies that have been developed to determine what the best auction for a particular case is. It discusses the advantages and disadvantages of each methodology and explores assumptions and robustness when confronted with data. To make these comparisons more straightforward, a unified notation is introduced and several methods are applied to the same auctions, uniform price auctions conducted by the government of Colombia.; Thesis (Ph.D, Economics) -- Queen's University, 2010-01-14 11:03:29.635

Optimal Bidding in Online Auctions

Bertsimas, Dimitris J.; Hawkins, Jeff; Perakis, Georgia
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Artigo de Revista Científica Formato: 508996 bytes; application/pdf
EN_US
Relevância na Pesquisa
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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)