Biblioteca Digital

O presente estudo mensura o impacto no preço dos atributos de qualidade nos tourinhos da raça Nelore comercializados em leilões por meio de uma metodologia específica, baseada na Teoria dos Preços Hedônicos. Para tanto, utilizou-se como amostra três leilões - 368 observações - de uma fazenda padrão, o Nelore Jandaia. Assim, os atributos dos animais que mais contribuíram para a formação dos preços, em um primeiro plano, foram: a qualidade genética como um todo, expressa através do Mérito Genético Total - MGT, e a qualidade fenotípica global, demonstrada pelo índice EPMURAS. Em um segundo plano, mais específico, agregaram mais valor aos jovens reprodutores características relacionadas à precocidade e fertilidade do lado genético a Diferença Esperada na Progênie - DEP para perímetro escrotal aos 365 dias (dpe365) e no lado fenotípico a nota de precocidade. Por exemplo, os animais com MGT excelente tiveram um prêmio médio de 22% a mais em relação aos considerados como bons, paralelamente os com EPMURAS excelente tiveram um prêmio de 11% em relação aos classificados como muito bons, ceteris paribus. Para cada ponto a mais na precocidade e na DEP dpe365 o valor dos animais comercializados aumenta em, respectivamente...

A seleção de fornecedores de transporte é um desafio cada vez maior. O crescimento da rede de clientes a ser coberta demanda uma alocação eficiente em termos de custo não suprida por mecanismos tradicionais de negociação. Neste âmbito, o leilão combinatório torna-se uma alternativa de negociação ao permitir capturar sinergias entre os trajetos que devem ser atendidos. Em conseqüência disso, diminui-se o custo de transporte do fornecedor que se reflete nos menores preços de suas propostas e finalmente no custo total de compra do serviço. Por outro lado, esta decisão envolve fatores além do custo total; a mensuração destes torna-se importante para identificar fornecedores que melhor se ajustam aos requerimentos do comprador. No entanto, é fundamental escolher um método adequado para sua avaliação porque este influência a decisão final. Este problema de compra de serviços de transporte é conhecido na literatura como Winner Determination Problem (WDP) que, devido a sua complexidade, possui uma resolução limitada. Após revisão teórica, foi observado que os estudos relacionados à área de transporte focalizavam o desenvolvimento de modelos matemáticos que fossem representativos da realidade. Alguns destes modelos abordam a utilização de múltiplos critérios atribuindo um coeficiente que pondera cada critério. Evidenciou-se a necessidade do desenvolvimento de um algoritmo alternativo que além de facilitar sinergias entre trajetos...

Este trabalho analisou os leilões de comercialização de energia elétrica no ambiente de contratação regulada no Brasil, realizados entre 2005 e 2011, com o objetivo de propor aperfeiçoamentos em sua metodologia. Para tanto, foram estudadas três linhas de pesquisa: teoria de leilões, internalização (adicionais) de custos não privados (externalidades) e organização de mercados de capacidade. Após a análise dos 21 leilões de novos empreendimentos realizados no período, conclui-se que o desenho do leilão com fase discriminatória final é adequado aos objetivos de modicidade tarifária, mas que também permite melhoras. As fraquezas da sistemática atual identificadas foram: metodologia de contratação termelétrica por disponibilidade, com viés das fontes de maior custo variável unitário, adoção de preço-teto nem sempre adequado, dificuldade em mitigar o exercício de poder de mercado da Eletrobras nos leilões de energia existente e licitação pelo custo econômico privado. De forma a aprimorar os leilões, as seguintes ações foram sugeridas: realização de uma etapa adicional e prévia ao desenho de leilão híbrido atual visando contornar a problemática de estabelecimento de preço-teto adequado; utilização de adicionais ao lance do leilão para internalizar os custos de transmissão não recolhidos pelo gerador; substituição do mecanismo de contratação termelétrica pelo modelo Colombiano de opções; condução de leilões de energia nova e existente em conjunto...

We examine the role of seller bidding and reserve prices in an infinitely repeated independent-private-value (IPV) ascending-price auction. The seller has a single object that she values at zero. At the end of any auction round, she may either sell to the highest bidder or pass-in the object and hold a new auction next period. New bidders are drawn randomly in each round. The ability to re-auction motivates a notion of reserve price as the option value of retaining the object for re-auctioning. Even in the absence of a mechanism with which to commit to a reserve price, the optimal “secret” reserve is shown to exceed zero. However, despite the infinite repetition, there may be significant value to the seller from a binding reserve price commitment: the optimal binding reserve is higher than the optimal “secret” reserve, and may be substantially so, even with very patient players. Furthermore, reserve price commitments may even be socially preferable at high discount factors. We also show that the optimal “phantom” bidding strategy for the seller is revenue-equivalent to a commitment to an optimal public reserve price.

Uma das fontes de receita mais lucrativas da internet são os anúncios para sites de busca. O crescimento deste mercado bilionário foi, em média, 20% ao ano nos últimos anos. Como o público alvo e variedade de anunciantes deste mercado são grandes e diversificados, um pequeno aumento da eficiência deste mecanismo representa um grande aumento de receita para os sites. Neste trabalho discutimos a evolução dos mecanismos usados neste mercado, identificando as razões destas mudanças. Avaliamos os mecanismos usados atualmente, modelando-o de formas diferentes e calculando o seu preço da anarquia.; Sponsored search auction is one of the most profitable sources of revenue on the internet. The growth of this market was, on average, 20% per year over the past years. Since the target audience and advertiser variety are big and diverse, a small increase in efficiency in this mechanism can bring a huge increase in the sites profits. In this work we discuss the evolution of the mechanisms used in this market, identifying the reasons of these changes. We evaluate the currently used mechanism, modeling in different ways and calculating the price of anarchy.

The purpose of this paper is to contribute to the multiple-units auction literature, by testing the performance of the dynamic Vickrey auction (the Ausubel model), in an experimental setting, representing the functioning of an emission permits market with an Ausubel auction for the initial allocation of permits. Other features of the experiment include the possibility of banking and the inclusion of uncertainty, and the parameters were set so as to replicate an environment similar to the EU-ETS market. Our results reveal that emission permits are not exactly allocated as theoretically predicted in the Ausubel auction although the differences are not statistically significant. Comparison of our results with previous experimental studies on the same auction mechanism, although under very different conditions, indicate no relevant differences exist on the Ausubel auction performance, which is an important policy indication when decisions are being taken on the implementation of several auctions for multiple units, namely in the context of the EU-ETS.; Fundação para a Ciência e a Tecnologia (FCT); We thank FCT for research support under grant POCTI/ECO/45435/02. Financial support from NIMA is also appretiated.

This paper proves the existence of the optimal all-pay auction when signals are correlated. In an all-pay auction every bidder pays his bid. The war of attrition is an auction in which every bidder but the winner pays his bid. The winner pays the second highest bid. Recently Krishna and Morgan showed that the war of attrition, if signals are correlated, dominates the all-pay auction. Examples in the paper show that the optimal all-pay auction may be optimal among all auctions and may dominate the war of attrition.

As traditional commerce moves on-line more business transactions will be mediated by software agents, and the ability of agent-mediated electronic marketplaces to efficiently allocate resources will be highly dependent on the complexity of the decision problems that agents face; determined in part by the structure of the marketplace, resource characteristics, and the nature of agents’ local problems. We compare auction performance for agents that have hard local problems, and uncertain values for goods. Perhaps an agent must solve a hard optimization problem to value a good, or interact with a busy and expensive human expert. Although auction design cannot simplify the valuation problem itself, we show that good auction design can simplify meta-deliberation - providing incentives for the “right” agents to deliberate for the “right” amount of time. Empirical results for a particular cost-benefit model of deliberation show that an ascending-price auction will often support higher revenue and efficiency than other auction designs. The price provides agents with useful information about the value that other agents hold for the good.; Engineering and Applied Sciences

Should a conceding authority auction off or negotiate a contract for an exclusive private infrastructure deal? Advocates of negotiation often argue that a formal competition may take too much time, that the costs of preparing bids may be excessive, and that innovation may be discouraged. But proponents of competitive bidding argue that there are ways to address theses concerns without sacrificing the bidding process. Moreover, they argue, competition may yield a better deal for the conceding authority and enhance the transparency of the process, making the transaction more politically sustainable. This Note examines the arguments.

Borrowing countries are increasingly inclined to use electronic procurement systems and means for processing and managing MDB funded activities. This guide is intended to be used for the application of e-reverse auctions during the procurement process. Not all procurement is suitable for e-reverse auction. Some governments consider e-reverse auction to be a special case of e-bidding while others see it as part of e-Purchasing. For United Nations Commission on International Trade Law (UNCITRAL), an e-reverse auction is described as an online, real-time dynamic auction between a buying organization and a number of suppliers who compete against each other to win the contract by submitting successively lower priced bids during a scheduled time period. Where e-GP systems are intended to be used for e-reverse auctions for works, goods, or services under MDB financed procurement, the MDB administering division or resident office administering the project will, consistent with any approved delegations, evaluate the e-reverse auction features...

In the context of the 2009 debate on reforming the Italian market, a realistic agent-based computational model of the day-ahead market session of the Italian wholesale electricity market is simulated to compare market performances between uniform-price and pay-as-bid clearing mechanisms. An empirical validation of computational results at a macro-level is performed to test for accuracy of simulated outcomes with historical ones. The level of prices are accurately reproduced except for few peak hours. As far as concerns pay-as-bid auction, the computational experiments point out that it results in higher market prices than the uniform-price auction. In the pay-as-bid mechanism, sellers’ endeavours to maximize their profits are more costly thus leading to higher price levels.

This research addresses the potential retention and cost impacts of providing an optimal individualized portfolio of non-monetary and monetary incentives to influence reenlistment and retention behavioral in enlisted Sailors. Specifically, it explores three mechanisms for administrating enlisted retention: a purely monetary auction, a Universal Incentive Package (UIP) auction, and the Combinatorial Retention Auction Mechanism (CRAM). In this text, the mechanisms are simulated, their outcomes compared and their respective strengths and weaknesses explored. The findings of this research confirm that CRAM clearly outperformed the monetary and UIP auctions. Cost savings to the Navy reanged from 25 to 80% over monetary incentives alone. Additionally, this research addresses the force-diversfying potential of CRAM. It is shown, for the sample used, that offering certain non-monetary incetives changed the demographic mix of Sailors retained. By allowing Sailors to choose only those benefits which suit them, the Navy can eliminate the waste associated with unwanted benefits, while at the same time empowering its members.

Approved for public release; distribution is unlimited.; Revised version; We propose a reverse uniform price auction called Combinatorial Retention Auction Mechanism (CRAM) that integrates both monetary and non-monetary incentives (NMIs). CRAM computes the cash bonus and NMIs to a single cost parameter, retains the lowest cost employees and provides them with compensation equal to the cost of the first excluded employee. CRAM is dominant strategy incentive compatible. We provide optimal bidding strategy, and show that there is cost saving compared to a benchmark auction (monetary retention auction). Because CRAM and the benchmark may retain different employees, we provide for whom and under what conditions the utility may increase or decrease by CRAM. Finally, we show that there is an increase in the total social welfare by utilizing CRAM to the benchmark.

The combinatorial clock-proxy auction is analyzed as a selling mechanism of a portion of the “digital dividend” in an European country. We assumed bidders with bounded rationality making their bidding decisions based on a system of recommendation that learns from the environment. The auction outcome when all bidders follow the proposed strategies was compared with the efficient outcome of the auction. Although significant differences were found in the seller’s income, no significant variations were found in the distribution of spectrum licenses among bidders.; This article has been financed by the Spanish research MCyT project MSTAR, Ref: TIN2008-06491-C04-03/TIN.

The increasing use of auctions as a selling mechanism has led to a growing interest in the subject. Thus both auction theory and experimental examinations of these theories are being developed. A recent method used for carrying out examinations on auctions has been the design of computational simulations. The aim of this article is to develop a genetic algorithm to find automatically a bidder optimal strategy while the other players are always bidding sincerely. To this end a specific dynamic multiunit auction has been selected: the Ausubel auction, with private values, dropout information, and with several rationing rules implemented. The method provides the bidding strategy (defined as the action to be taken under different auction conditions) that maximizes the bidder's payoff. The algorithm is tested under several experimental environments that differ in the elasticity of their demand curves, number of bidders and quantity of lots auctioned. The results suggest that the approach leads to strategies that outperform sincere bidding when rationing is needed.

Sponsored Report (for Acquisition Research Program); The current fiscal crisis has placed unprecedented pressure on public procurements. A major target of future public spending cuts is likely to be defense expenditures. Within the defense budget, the biggest and most immediate targets are likely to be the acquisition of new equipment, facilities, services, and supplies. Addressing the growing global challenge of affordability, this paper offers a new approach to government''s vendor selection decisions in major public procurements. In the absence of profits to guide public procurement decisions, the challenge that faces a government buyer is to select the vendor that delivers the best combination of desired non-price attributes at realistic funding levels. The governance mechanism proposed in this paper is a multiattribute first price, sealed bid procurement auction. It extends traditional price-only auctions to one in which competition takes place exclusively over bundles of desired non-price attributes. The first iteration of the model is a multiattribute auction in which a fixed budget constraint is specified. Next, the model is expanded to incorporate a range of possible budget levels. This expanded model reveals the benefits to the buyer of defining a procurement alternative (vendor bid proposal) in terms of its value to the buyer over a range of possible expenditures...

The dissertation highlights different topics of equity trading in limit order books using the example of Deutsche Boerse's electronic trading system XETRA. The first introductory chapter is a straight forward discussion of the profitability of exchange trading for both the exchange operator and the liquidity suppliers. It applies Harris and Hasbrouck(1996) for the continuous trading and extends it to the auction phase. The second chapter analyzes the impact of adverse selection on liquidity provision. It relaxes the the assumptions of Sandas(2001) empirical implementation of the theoretical model outlined in Glosten(1994) in two dimensions. Replacing the marginal profit conditions with average ones improves the empirical performance, whereas the nonparametric specification of the market order size does not. A cross sectional analysis corroborates the finding that adverse selection costs are more severe for smaller capitalized stocks. Iceberg orders allow traders to submit hidden liquidity into the order book. The third chapter studies the interaction between hidden liquidity and overall liquidity provision. It provides evidence that iceberg orders can be detected using public information and that market participants follow state-dependent order submission strategies. At times of iceberg orders prevailing in the order book the marker order flow and price impact changes. After adjusting for those effects in the Glosten/Sandas framework the marginal compensation of liquidity provision changes. The fourth chapter changes the focus to the opening auction. It proposes an extension to Biais et al.(1999) to remove the market microstructure noise of the indicative price regression. The results show that the indicative price becomes informative about the true value at the very beginning of the call phase...

Standard auction mechanisms often break down in important e-commerce applications, where agents demand bundles of complementary resources, i.e. "I only want B if I also get A". This paper describes iBundle, an ascending-price auction that is guaranteed to compute optimal bundle allocations with agents that follow a best-response bidding strategy. The auction prices bundles directly and allows agents to place additive or exclusive-or bids over collections of bundles. Empirical results confirm that iBundle generates efficient allocations for hard resource allocation problems. Furthermore, we shoe that iBundle generates solutions without complete revelation (or computation) of agent preferences.; Engineering and Applied Sciences

The uniform-price auction is used in many regional electricity procurement auctions and its “collusive-seeming equilibria” have been linked to potential exercise of market power. Such equilibria do not exist, however, if a small amount of cash is split among rationed bidders. To shed light on what drives this result, I also examine variations in which the auctioneer is able to increase and/or decrease quantity after receiving the bids. “Increasable demand” also eliminates all collusive-seeming equilibria. These results suggest ways to modify the uniform-price auction in order to reduce the potential exercise of market power.