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Causas de variação nos preços de bovinos nelore elite no Brasil; Causes of variation in the prices of nelore elite cattle in Brazil

PANETO, João Cláudio do Carmo; BITTAR, Eustáquio Resende; BARBOSA, Eugênio Faria; ROCHA, Carina Diniz; VAL, José Eduardo do; FERRAUDO, Antônio Sergio; LÔBO, Raysildo Barbosa
Fonte: Universidade Federal de Santa Maria Publicador: Universidade Federal de Santa Maria
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
36.65%
Este trabalho teve por objetivo estudar as causas de variação nos preços de bovinos da raça nelore pertencentes a rebanhos de seleção, os quais foram comercializados em leilões, para verificar as influências das avaliações genéticas e dos julgamentos de exterior sobre esses preços. Para tanto, foram computados os preços de venda de 426 bovinos da referida raça em 12 leilões ocorridos em diversas localidades brasileiras (regiões Centro-Oeste, Norte e Sudeste), entre os anos de 2002 e 2005. O valor médio foi de R$ 3.325,49, sendo o mínimo de R$ 1.400,00 e o máximo de R$ 10.500,00. Esses dados foram digitados juntamente com outras informações que eram apresentadas nos catálogos dos leilões. As informações registradas incluíram o sexo de cada animal, o nome do leilão e as DEPs informadas nos catálogos. Além da avaliação da influência das informações dos catálogos, também foi avaliada a influência das informações dos reprodutores, pais dos animais vendidos nos leilões, envolvendo suas DEPs publicadas em um sumário de reprodutores da raça e as pontuações de suas progênies em julgamentos. Os métodos estatísticos aplicados foram análises de variâncias e análises de agrupamento (método K-médias). Como resultado...

Adjusting prices in the multiple-partners assignment game

SOTOMAYOR, Marilda
Fonte: SPRINGER HEIDELBERG Publicador: SPRINGER HEIDELBERG
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.44%
Starting with an initial price vector, prices are adjusted in order to eliminate the excess demand and at the same time to keep the transfers to the sellers as low as possible. In each step of the auction, to which set of sellers should those transfers be made is the key issue in the description of the algorithm. We assume additively separable utilities and introduce a novel distinction by considering multiple sellers owing multiple identical objects and multiple buyers with an exogenously defined quota, consuming more than one object but at most one unit of a seller`s good and having multi-dimensional payoffs. This distinction induces a necessarily more complicated construction of the over-demanded sets than the constructions of these sets for the other assignment games. For this approach, our mechanism yields the buyer-optimal competitive equilibrium payoff, which equals the buyer-optimal stable payoff. The symmetry of the model allows to getting the seller-optimal stable payoff and the seller-optimal competitive equilibrium payoff can then be also derived.

Avaliação do impacto dos atributos de qualidade em tourinhos de elite da raça nelore comercializados em leilão: uma aplicação do método hedônico; Impact of quality attributes in the price of Nellore breed sold at auction: an application of the hedonic

Calil, Yuri Clements Daglia
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 27/08/2010 PT
Relevância na Pesquisa
36.39%
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...

Seleção de fornecedores de serviço de transporte utilizando leilão combinatório de compras: adaptação e aplicação do algoritmo Iterative Deepening Search A* (IDA*).; Supplier selection of transportation services using reverse combinatorial auction: adaptation and aplication of Iterative Deepening Search A* (IDA*).

Higuita Salazar, Catalina
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 15/12/2011 PT
Relevância na Pesquisa
36.46%
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...

Proposta de aperfeiçoamento da metodologia dos leilões de comercialização de energia elétrica no ambiente regulado: aspectos conceituais, metodológicos e suas aplicações; Proposal for Improving Methodology of Regulated Electricity Procurement Auction: Concepts, Methodologies, and Their Applications

Rego, Erik Eduardo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 05/11/2012 PT
Relevância na Pesquisa
36.51%
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...

Auctions with options for re-auction

Menezes, Flavio Marques
Fonte: Escola de Pós-Graduação em Economia da FGV Publicador: Escola de Pós-Graduação em Economia da FGV
Tipo: Relatório
EN_US
Relevância na Pesquisa
36.55%
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.

A simultaneous descending bid auction for multiple items and unitary demand

Sotomayor,Marilda
Fonte: Fundação Getúlio Vargas Publicador: Fundação Getúlio Vargas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2002 EN
Relevância na Pesquisa
36.44%
This paper proposes a new descending bid method for auctioning multiple objects. The auctioneer announces a current price, bidders indicate their demands at that price, and the auctioneer lowers the prices until every object can be allocated to a buyer who demands it and no buyer receives more than one item. The features of this mechanism lie on the facts that: the objects are sold simultaneously at prices that clear the market; every two similar objects are sold at the same price; the mechanism always produces the same final price, namely, the maximum competitive equilibrium price. In addition, the auctioneer can choose an efficient allocation.

From Uniform Auction to Discriminatory Auction: Assessment of the Restructuring Proposal for the Italian Electricity Day-Ahead Market

GUERCI, Eric; RASTEGAR, Mohammad Ali
Fonte: Instituto Universitário Europeu Publicador: Instituto Universitário Europeu
Tipo: Trabalho em Andamento Formato: application/pdf; digital
EN
Relevância na Pesquisa
36.74%
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.

Liquidity Provision in the Limit Order Book - Adverse Selection, Iceberg Orders and the Opening Auction; Liquiditätsangebot im Orderbuch - Adverse Selektion, Iceberg Orders und die Eröffnungsauktion

Frey, Stefan
Fonte: Universität Tübingen Publicador: Universität Tübingen
Tipo: Dissertation; info:eu-repo/semantics/doctoralThesis
EN
Relevância na Pesquisa
36.51%
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...

An Empirical Investigation of the Nexus among Money Balances, Commodity Prices and Consumer Goods’ Prices

Grigoli, Francesco
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Publications & Research :: Policy Research Working Paper
ENGLISH
Relevância na Pesquisa
36.76%
This paper aims to identify the nexus between the excess of liquidity in the United States and commodity prices over the 1983-2006 period. In particular, it assesses whether commodity prices react more powerfully than consumer goods' prices to changes in real money balances. Within a cointegrated vector autoregressive framework, the author investigates whether consumer prices and commodity prices react to excess liquidity, and if the different price elasticities of supply for goods and commodities allow for differences in the dynamic paths of price adjustment to a liquidity shock. The results show a positive relationship between real money and real commodity prices and provide empirical evidence for a stronger response of commodity prices with respect to consumer goods' prices. This could imply that, if the magnitude of the reaction is due the fact that consumer goods' prices are slower to react, then their long-run value can be predicted with the help of commodity prices. The findings support the view that the latter should be considered as a valid monetary indicator.

Measuring the Impact of a Change in the Price of Cashew Received by Exporters on Farmgate Prices and Poverty in Guinea-Bissau

Cont, Walter; Porto, Guido
Fonte: World Bank Group, Washington, DC Publicador: World Bank Group, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
36.49%
This paper assesses the impact of a change in the price of cashew received by exporters in general -- and by FUNPI, a fund to promote the industrialization of agricultural products, in particular -- on farmgate prices and poverty in Guinea-Bissau. The analysis builds a theoretical model of supply chains in export agriculture that includes exporters, traders, and farmers competing in a bilateral oligopoly fashion. The model is adapted to data from the country's cashew sector and a household survey. Given the market structure, a shock on export prices or the introduction of an export tax, such as the FUNPI contribution, has a strong effect on farmgate prices, as farmers absorb about 80 percent of the tax (while exporters take up 13 percent and traders absorb the remaining 7 percent). The effect is uneven across households, as poor rural households are more exposed to price volatility and most cashew farmers are poor. It is estimated that their income falls by 12 percent as a result of the FUNPI contribution. Complementary policies can overcome the effect of the FUNPI surcharge on farmgate prices by aiming for reductions in transport...

High Food Prices, Latin American and the Caribbean Responses to a New Normal; El alto precio de los alimentos, respuestas de ALC a una nueva normalidad

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
36.49%
Yet the current situation differs from 2007-2008 in critical respects. First, recent international price increases are more widespread across agricultural commodities than in 2008, when price spikes were led by few grains such as wheat and rice. Second, natural resources are affecting food production: land and water constraints are more binding than in the past and weather induced production shortfalls are more of a factor now than it was 2008. Climate change also adds to this uncertainty, particularly since a larger share of grain exports are being produced in areas more exposed to climate variability. Third, long term structural changes in the markets are more clearly a major factor this time, as demand for feed and income-elastic foods under sustained and widespread income growth in emerging countries is increasing steadily. Fourth, the global stocks/use ratio for major cereals, which used to hover in the range of 30-35 percent in the 1980s and 1990s, has been around 20 percent after 2003 due largely to long-term policy changes in high-income countries; and stocks of some critical players are now at all-time lows. Global markets are currently experiencing the second sharp spike in food prices in the last four years. While no one has a crystal ball to predict with confidence the future prices of food products...

Performance of Renewable Energy Auctions : Experience in Brazil, China and India

Elizondo Azuela, Gabriela; Barroso, Luiz; Khanna, Ashish; Wang, Xiaodong; Wu, Yun; Cunha, Gabriel
Fonte: World Bank Group, Washington, DC Publicador: World Bank Group, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
37.05%
This paper considers the design and performance of auction mechanisms used to deploy renewable energy in three emerging economies: Brazil, China, and India. The analysis focuses on the countries' experience in various dimensions, including price reductions, bidding dynamics, coordination with transmission planning, risk allocation strategies, and the issue of domestic content. Several countries have turned to public competitive bidding as a mechanism for developing the renewable generation sector in recent years, with the number of countries implementing some sort of auction procedure rising from nine in 2009 to 36 by the end of 2011 and about 43 in 2013. In general, the use of auctions makes sense when the contracting authority expects a large volume of potentially suitable bids, so that the gains from competition can offset the costs of implementation. A study of the successes and failures of the particular auction design schemes described in this paper can be instrumental in informing future policy making.

What Factors Determine Auction Prices in Privatization?

López-de-Silanes, Florencio
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Viewpoint; Publications & Research
ENGLISH
Relevância na Pesquisa
46.53%
Do the timing and type of auction affect the sale price? What kind of restructuring is worth doing before privatization? The author examines how much these and other factors affect privatization prices. The study shows that speed and competitive bidding consistently increase sale premiums, but that many restructuring measures such as absorbing debt and improving efficiency do not. The key lesson for policymakers: Don't do too much --just sell.

Temporary and Permanent Buyout Prices in Online Auctions

Gupta, Shobhit; Gallien, Jérémie
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Tipo: Artigo de Revista Científica Formato: 251636 bytes; application/pdf
EN
Relevância na Pesquisa
36.65%
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)

The Sequential Auction Problem on eBay: An Empirical Analysis and a Solution

Juda, Adam I.; Parkes, David C.
Fonte: Association for Computing Machinery Publicador: Association for Computing Machinery
Tipo: Monograph or Book
EN_US
Relevância na Pesquisa
36.56%
Bidders on eBay have no dominant bidding strategy when faced with multiple auctions each offering an item of interest. As seen through an analysis of 1,956 auctions on eBay for a Dell E193FP LCD monitor, some bidders win auctions at prices higher than those of other available auctions, while others never win an auction despite placing bids in losing efforts that are greater than the closing prices of other available auctions. These misqueues in strategic behavior hamper the efficiency of the system, and in so doing limit the revenue potential for sellers. This paper proposes a novel options-based extension to eBay's proxy-bidding system that resolves this strategic issue for buyers in commoditized markets. An empirical analysis of eBay provides a basis for computer simulations that investigate the market effects of the options-based scheme, and demonstrates that the options-based scheme provides greater efficiency than eBay, while also increasing seller revenue.; Engineering and Applied Sciences

iBundle: An Efficient Ascending Price Bundle Auction

Parkes, David C.
Fonte: Association for Computing Machinery Publicador: Association for Computing Machinery
Tipo: Monograph or Book
EN_US
Relevância na Pesquisa
46.51%
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

License Prices for Financially Constrained Firms

Burguet, Roberto; McAfee, R. Preston
Fonte: Conselho Superior de Investigações Científicas Publicador: Conselho Superior de Investigações Científicas
Tipo: Documento de trabajo Formato: 243845 bytes; application/pdf
ENG
Relevância na Pesquisa
56.7%
36 pages, 1 figure.-- Trabajo publicado como artículo en Journal of Regulatory Economics 36(2): 178-198 (2009).-- http://dx.doi.org/10.1007/s11149-009-9092-5; It is often alleged that high auction prices inhibit service deployment. We investigate this claim under the extreme case of financially constrained bidders. If demand is just slightly elastic, auctions maximize consumer surplus if consumer surplus is a convex function of quantity (a common assumption), or if consumer surplus is concave and the proportion of expenditure spent on deployment is greater than one over the elasticity of demand. The latter condition appears to be true for most of the large telecom auctions in the US and Europe. Thus, even if high auction prices inhibit service deployment, auctions appear to be optimal from the consumers' point of view.; Burguet acknowledges partial financial support from CREA and the Spanish Ministry of Education and Science, project SEJ2005-01427.; Peer reviewed

License prices for financially constrained firms

Burguet, Roberto; McAfee, R. Preston
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Trabalho em Andamento Formato: application/pdf
Publicado em //2008 ENG
Relevância na Pesquisa
36.53%
It is often alleged that high auction prices inhibit service deployment. We investigate this claim under the extreme case of financially constrained bidders. If demand is just slightly elastic, auctions maximize consumer surplus if consumer surplus is a convex function of quantity (a common assumption), or if consumer surplus is concave and the proportion of expenditure spent on deployment is greater than one over the elasticity of demand. The latter condition appears to be true for most of the large telecom auctions in the US and Europe. Thus, even if high auction prices inhibit service deployment, auctions appear to be optimal from the consumers' point of view.

License prices for financially constrained firms

Burguet, Roberto; McAfee, R. Preston
Fonte: Springer Publicador: Springer
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em /10/2009
Relevância na Pesquisa
36.53%
It is often alleged that high auction prices inhibit service deployment. We investigate this claim under the extreme case of financially constrained bidders. If demand is just slightly elastic, auctions maximize consumer surplus if consumer surplus is a convex function of quantity (a common assumption), or if consumer surplus is concave and the proportion of expenditure spent on deployment is greater than one over the elasticity of demand. The latter condition appears to be true for most of the large telecom auctions in the US and Europe. Thus, even if high auction prices inhibit service deployment, auctions appear to be optimal from the consumers’ point of view.