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## Why do bidders drop out from a sequential auction

Engelbrecht-Wiggans,Richard; Menezes,Flavio M.
Fonte: Fundação Getúlio Vargas Publicador: Fundação Getúlio Vargas
Tipo: Artigo de Revista Científica Formato: text/html
Relevância na Pesquisa
27.35%
In actual sequential auctions, bidders typically incur a cost in continuing from one sale to the next, and they decide whether or not to continue. To investigate the question "why do bidders drop out', this paper defines a sequential auction model with continuation costs and an endogenously determined number of bidders at each sale, and characterizes the equilibria in this model. Simple examples illustrate the effect of several possible changes to this model.

## Strong Activity Rules for Iterative Combinatorial Auctions

Harsha, Pavithra; Barnhart, Cynthia; Parkes, David C.; Zhang, Haoqi
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...

## On Revenue-Optimal Dynamic Auctions for Bidders with Interdependent Values

Constantin, Florin; Parkes, David C.
Tipo: Monograph or Book
EN_US
Relevância na Pesquisa
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In a dynamic market, being able to update one’s value based on information available to other bidders currently in the market can be critical to having profitable transactions. This is nicely captured by the model of interdependent values (IDV): a bidder’s value can explicitly depend on the private information of other bidders. In this paper we present preliminary results about the revenue properties of dynamic auctions for IDV bidders. We adopt a computational approach to design single-item revenue-optimal dynamic auctions with known arrivals and departures but (private) signals that arrive online. In leveraging a characterization of truthful auctions, we present a mixed-integer programming formulation of the design problem. Although a discretization is imposed on bidder signals the solution is a mechanism applicable to continuous signals. The formulation size grows exponentially in the dependence of bidders’ values on other bidders’ signals. We highlight general properties of revenue-optimal dynamic auctions in a simple parametrized example and study the sensitivity of prices and revenue to model parameters.; Engineering and Applied Sciences

## Bidders’ Entry and Auctioneer’s Rejection : Applying a Double Selection Model to Road Procurement Auctions

Estache, Antonio; Iimi, Atsushi
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
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Limited competition has been a serious concern in infrastructure procurement. Importantly, however, there are normally a number of potential bidders initially showing interest in proposed projects. This paper focuses on tackling the question why these initially interested bidders fade out. An empirical problem is that no bids of fading-out firms are observable. They could decide not to enter the process at the beginning of the tendering or may be technically disqualified at any point in the selection process. This paper applies the double selection model to procurement data from road development projects in developing countries and examines why competition ends up restricted. It shows that bidders are self-selective and auctioneers also tend to limit participation depending on the size of contracts. Therefore, limited competition would likely lead to high infrastructure procurement costs.

## Bidder Asymmetry in Infrastructure Procurement: Are There Any Fringe Bidders?

Estache, Antonio; Iimi, Atsushi
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
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Asymmetric auctions are among the most rapidly growing areas in the auction literature. The potential benefits from intensified auction competition could be enormous in the public procurement context. Entrant bidders are considered a key to enhance competition and break potential collusive arrangements among incumbent bidders. Asymmetric auction theory predicts that weak (fringe) bidders would bid more aggressively when they are faced with a strong (incumbent) opponent. Using data from official development projects, this paper shows that entrants actually submitted aggressive bids in the presence of incumbent(s) in the road sector and to a certain extent in the water sector. For electricity projects, the general competition effect is found to be particularly significant, but the entrant effect remains unclear. The results suggest that auctioneers should foster competition in public procurement, including fringe bidders, to contain public infrastructure investment costs.

## Bidder Asymmetry in Infrastructure Procurement : Are There Any Fringe Bidders?

Estache, Antonio; Iimi, Atsushi
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Relevância na Pesquisa
37.54%
Asymmetric auctions are among the most rapidly growing areas in the auction literature. The potential benefits from improved auction efficiency are expected to be enormous in public procurement auctions related to official development projects. Entrant bidders are considered a key to enhance competition in an auction and break potential collusive arrangements among incumbent bidders. Asymmetric auction theory predicts that weak (fringe) bidders would bid more aggressively when they are faced with a strong (incumbent) opponent. Using official development assistance procurement data, this paper finds that in the major infrastructure sectors, entrants submitted systematically aggressive bids in the presence of an incumbent bidder. The findings also show that a high concentration of incumbents in an auction would harm auction efficiency, raising procurement costs. The results suggest that auctioneers should encourage fringe bidders to actively participate in the bidding process while maintaining the quality of the projects. This is conducive to enhancing competitive circumstances in public procurements and improving allocative efficiency.

## Strategic Bidding in Multi-unit Auctions with Capacity Constrained Bidders: The New York capacity market

SCHWENEN, Sebastian
Fonte: Instituto Universitário Europeu Publicador: Instituto Universitário Europeu
Tipo: Trabalho em Andamento Formato: application/pdf; digital
EN
Relevância na Pesquisa
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This paper employs a simple model to describe bidding behavior in multi-unit uniform price procurement auctions when firms are capacity constrained. Using data from the New York City capacity auctions, I find that capacity constrained firms use simple bidding strategies to co-ordinate on an equilibrium that extracts high rents for all bidders. I show theoretically and empirically that the largest bidder submits the auction clearing bid. All other bidders submit infra-marginal bids that are low enough to not be profitably undercut. Infra-marginal bidders react to capacity endowments and decrease their bids as the largest firm’s capacities and its profits of undercutting increase. Capacity markets, when designed as studied here, are a costly tool to increase security of supply in electricity markets, as capacity prices do not reflect actual capacity scarcity.

## Successful uninformed bidding

Hernando-Veciana, Ángel
Tipo: Trabalho em Andamento Formato: application/pdf
Relevância na Pesquisa
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This paper provides some striking results that arise in the unique symmetric equilibrium of common value multiunit auction in which some bidders are better informed than others. We show that bidders with worse information can do surprisingly well: They can win with higher probability than better informed bidders, and sometimes, even with higher expected utility. We also find a positive relationship between the success of worse informed bidders and the number of units for sale. Finally we argue that the correct intuitive explanation of these results relies on the balance of the winner’s curse and the loser’s curse effects.

## On the Sub-Optimality of Entry Fees in Auctions with Entry

Hernando-Veciana, Ángel
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article
Relevância na Pesquisa
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We study a variation of Myerson’s (1981) model in which we allow for uncertainty about the number of bidders. In our set-up, an appropriate reserve price in a standard auction maximizes the auctioneer’s expected revenue. However, entry fees can be optimal only under some special conditions. Basically, theremust be some homogeneity in bidders’ beliefs about the number of bidders and the auctioneer must know, to some extent, these beliefs.; The original publication is available at www.springerlink.com

## Successful uninformed bidding

Hernando-Veciana, Ángel
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article
Relevância na Pesquisa
27.54%
This paper provides some striking results that arise in the unique symmetric equilibrium of common value multi-unit auctions in which some bidders have more information than others. We show that in a generalized second price auction with single-unit demand, bidders with less information do surprisingly well: they can have a greater probability of winning than bidders with more information do, and may even have a higher expected utility. We also find a positive relationship between the success of less-informed bidders and a ratio of units for sale to bidders.

## Successful uninformed bidding

Hernando-Veciana, Ángel
Tipo: Trabalho em Andamento Formato: application/pdf
Relevância na Pesquisa
27.46%
This paper studies multiunit common value auctions with informed and less informed bidders. In these auctions, we show that bidders with less information can bid very aggressively and do surprisingly well. We also show that the degree of aggressiveness and success of bidders with less information is positively related to the number of units for sale. We explain these phenomena in terms of the balance of the winner's curse and the loser's curse and their di erential e ect on bidders with di erent quality of information.

## (SUB-)Optimal entry fees

Hernando-Veciana,Ángel
Tipo: Trabalho em Andamento Formato: application/pdf
Relevância na Pesquisa
27.18%
We extend Myerson's (1981) model by allowing for uncertainty about the number of bidders. In such extension the Revenue Equivalence Theorem still holds and the optimal allocation rule remains the same. Hence, the optimal auction can be implemented with an appropriate reserve price. Nonetheless, we show that entry fees are sub-optimal. The reasons are heterogeneity in bidders' beliefs about the number of bidders, and auctioneer's uncertainty about the optimum entry fee, if any. Our result implies a reversal of the revenue ranking by Milgrom and Weber (1982) which is consistent with many real life situations: auction houses, internet auctions,...

## Georgia : Country Procurement Assessment Report

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Country Procurement Assessment (CPAR); Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
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In light of its strategy for an accelerated transition to a market economy, Georgia has made tremendous efforts to provide a legal base for the required changes, and has adopted a multitude of laws at a rapid pace, starting in 1993. With the notable exception of enforcement provisions, the scope of existing Georgian legal instruments, would be adequate to control the procurement process in Georgia, if they were widely followed. The main issue is not the lack of legislation, but rather the effective application of the legislation that is already in place. Nevertheless, the Government's determination, and technical assistance provided under a Bank Institutional Development Fund, public procurement is now guided by a single overarching law. But, despite an acceleration in establishing a sound legal framework, the procurement reform agenda has not yet been completed, and procurement reform is going very slowly. Within this context, this Country Procurement Assessment Report (CPAR) recommends that: the list of procurement...

## Philippines : Country Procurement Assessment Report

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Country Procurement Assessment (CPAR); Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
27.35%
Every year, the Philippine government spends hundreds of billions of pesos to buy the goods and services it needs to carry out projects and deliver services to its citizens. This money comes from the budget that it funds out of its own revenues and from loans and grants extended by foreign sources such as multilateral development banks and bilateral donors. Deciding how to spend this money is a very important responsibility on the part of government leaders and officials, not only because of the large amounts but also the public trust involved. Citizens and taxpayers have a right to expect that their government will spend these funds wisely and honestly, for the greatest public good. Procurement is a key step in the process of getting the best value for the people's peso. The process involves announcing or advertising what the government needs, inviting qualified parties or individuals to offer their bids, evaluating those bids, awarding contracts to the chosen bidders, monitoring their delivery and performance, paying them and recording the results of the whole process for others to see. It also involves making sure that the bidding is fair and transparent to all...

## número pequeño y limitado de proponentes para los procesos de contratación pública establecido para el batallon apoyo y servicios para el combate no. 21; SMALL NUMBER OF BIDDERS AND LIMITED FOR PROCUREMENT PROCESS ESTABLISHED FOR SERVICE AND SUPPORT BATTALION TO FIGHT No. 21

Orozco Suarez, Farid Albeiro; Salazar Gonzalez, Jair Antonio
Tipo: bachelorThesis; Trabajo de grado Formato: pdf; pdf
SPA
Relevância na Pesquisa
37.35%

## Forward-looking bidders in sequential auctions

Zeithammer, Robert, 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 97 leaves; 4273697 bytes; 4273505 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
27.18%
At Internet auction sites like eBay, similar goods are often sold in a sequence of auctions. Buyers can therefore benefit from forward-looking bidding strategies that take into account the available information about future auctions. This dissertation develops a model of such bidding, provides both experimental and econometric evidence of the model's relevance to behavior, and explores the impact of forward-looking bidding on the seller's optimal selling strategy as well as on the overall market equilibrium. Extending prior sequential-auction theories, the proposed model assumes that bidders know their private valuations of objects auctioned in the near future. Rational bidders "bargain-hunt" in that they bid less than they would otherwise, and early bids decrease with the private values of later objects. The model's predictions are tested in two laboratory experiments, both involving a sequence of two auctions. Both experiments show that first-auction bids decrease with the private values of the future object, but the second experiment suggests that the average decrease is smaller than predicted by the theory. An econometric analysis of eBay data finds that buyers seem to look ahead, and on average adjust their bids down as a function of their private preferences for the objects sold in the near future. They also bid less when the same item they are bidding on is available within the next few auctions. To explore the supply-side of a sequential auction marketplace...

## Online Auctions for Bidders with Interdependent Values

Constantin, Florin; Ito, Takayuki; Parkes, David C.
Fonte: Association for Computing Machinery Publicador: Association for Computing Machinery
Tipo: Monograph or Book
EN_US
Relevância na Pesquisa
27.46%
Interdependent values (IDV) is a valuation model allowing bidders in an auction to express their value for the item(s) to sell as a function of the other bidders' information. We investigate the incentive compatibility (IC) of single-item auctions for IDV bidders in dynamic environments. We provide a necessary and sufficient characterization for IC in this setting. We show that if bidders can misreport departure times and private signals, no reasonable auction can be IC. We present a reasonable IC auction for the case where bidders cannot misreport departures.; Engineering and Applied Sciences

## Selling to Risk-Loving Bidders

Tipo: Artigo de Revista Científica
Relevância na Pesquisa
27.46%
We propose a new all-pay auction format in which risk-loving bidders pay a constant fee each time they bid for an object whose monetary value is common knowledge among the bidders, and bidding fees are the only source of benefit for the seller. We show that for the proposed model there exists a Symmetric Subgame Perfect Equilibrium (SSPE) which is unique. The characterized SSPE is stationary when re-entry in the auction is allowed and it is Markov perfect when re-entry is forbidden. Furthermore, we fully characterize the expected revenue of the seller. We show that the expected revenue of the seller is independent of the number of bidders, decreasing in the sale price, increasing in the value of the object and decreasing in the bidding fee. Moreover, we show that the seller's revenue is equal to the values of the object when players are risk neutral and strictly greater than the value of the object when bidders are risk-loving. Finally, we demonstrate the importance of allowing re-entry by showing that without re-entry, the auction would last a long time and for almost all of its duration have only two remaining players.

## Optimal Auctions with Correlated Bidders are Easy

Dobzinski, Shahar; Fu, Hu; Kleinberg, Robert
Tipo: Artigo de Revista Científica
We consider the problem of designing a revenue-maximizing auction for a single item, when the values of the bidders are drawn from a correlated distribution. We observe that there exists an algorithm that finds the optimal randomized mechanism that runs in time polynomial in the size of the support. We leverage this result to show that in the oracle model introduced by Ronen and Saberi [FOCS'02], there exists a polynomial time truthful in expectation mechanism that provides a $(\frac 3 2+\epsilon)$-approximation to the revenue achievable by an optimal truthful-in-expectation mechanism, and a polynomial time deterministic truthful mechanism that guarantees $\frac 5 3$ approximation to the revenue achievable by an optimal deterministic truthful mechanism. We show that the $\frac 5 3$-approximation mechanism provides the same approximation ratio also with respect to the optimal truthful-in-expectation mechanism. This shows that the performance gap between truthful-in-expectation and deterministic mechanisms is relatively small. En route, we solve an open question of Mehta and Vazirani [EC'04]. Finally, we extend some of our results to the multi-item case, and show how to compute the optimal truthful-in-expectation mechanisms for bidders with more complex valuations.