Oct 21 2008 One of the Points Paul Milgrom Always Stress

Total Page:16

File Type:pdf, Size:1020Kb

Oct 21 2008 One of the Points Paul Milgrom Always Stress Econ 805 { Advanced Micro Theory I Dan Quint Fall 2008 Lecture 13 { Oct 21 2008 One of the points Paul Milgrom always stressed when teaching about auctions: \the game is always larger than you think." The ¯rst several weeks of this course focused on models of auctions where the bidders have already shown up, knowing what they know, and play noncooperative equilibrium strategies. But we can also step back and think about the bigger game { these bidders have to come from somewhere and decide to show up (endogenous participation/entry), there's a reason they know what they know (endogenous information), and under some circumstances, they may try to collude which each other or otherwise discourage participation. Changes to the auction itself may have a direct impact on revenue, even keeping this other factors ¯xed; but they may also a®ect the number of bidders who choose to participate, the amount of information they choose to acquire, how easy it is for them to collude with each other, and so on. In his book, Klemperer emphasizes that these problems { ensuring adequate genuine competition { often dwarf whatever di®erences there would otherwise be between di®erent types of auctions. Last Tuesday, we introduced models of auctions with endogenous entry. Last Thursday, we discussed a couple of papers on endogenous information acquisition. Today, I want to talk a bit more about endogenous information, and also a bit about collusion and other deviations from noncooperative equilibrium play. The two papers we saw on Thursday made polar opposite assumptions about whether \well- informed" bidders were known to be well-informed: ² The Persico paper assumed that information acquisition was covert. Bidders simultaneously choose how accurate a signal to observe (or how much to invest in information acquisition), learn their signal, but do not observe the choices made by their competitors. Persico ¯nds that ¯rst-price auctions are more risk-sensitive than second-price auctions { basically, better information is more valuable in a ¯rst-price auction, so a ¯rst-price auction leads to greater information acquisition. (This is in a slightly-modi¯ed Milgrom-Weber a±liated world.) Per- sico also points out that this can lead to a reversal of the linkage principle { with exogenous information and a±liation, second-price auctions revenue-dominate ¯rst-price auctions; but with endogenous information, this can be flipped. ² Hernando-Veciana, on the other hand, assumed that information acquisition was public { bid- ders observe each others' decisions about how accurate a signal to invest in. He uses a more rigidly structured model { the winner's value is the sum of a private-value component and a common-value component, and each bidder's signal is one-dimensional but contains informa- tion about both components. He ¯nds that which type of auction induces greater information 1 acquisition depends on which component of value (the PV or CV bit) the incremental infor- mation is about. If a better signal is more informative about the common-value component, then sealed-bid auctions induce more information acquisition than ascending auctions. If a better signal is more informative about the private-value component, then (roughly) the op- posite: ascending auctions induce more information acquisition. He also shows that in both cases, e±ciency (roughly) favors ascending auctions. So that's one paper that considers covert information acquisition, and one that considers observ- able (open) information acquisition. My own paper, \Common Value Auctions with Two Bidders { When To Brag About What You Know," compares the two. That is, I ask the question, if you had a choice between gaining better information covertly or openly, which would a bidder prefer? In other words, aside from the obvious bene¯t of having better information, is there an additional gain (or a loss) from appearing to have better information. The answer turns out to depend on the nature of this incremental information { whether it is independent or highly correlated with the other bidder's signal. I restrict attention to the two-bidder case, with pure common values. Rather than signal accuracy being a continuous variable, I make it discrete { speci¯cally, I look at the value of observing an additional signal in addition to the one you started with. Most of my results are generalizations of those from the drainage tract auction (common-value auctions with just one bidder having private information) to both bidders have private information. I assume the common value V is additively separable into two independent components, V = V1 + V2 I assume there are two signals, X and Y , which are correlated with V1, and two signals, Z and W , which are correlated with V2; and that (V1; X; Y ) are independent of (V2; Z; W ). The \base case" will be bidder 1 observing X (but not Y ), and bidder 2 observing both Z and W . This way, we can look at the incremental e®ect of bidder 1 learning Y (information which is independent of his opponent's, which I'll refer to as novel information) or learning Z (information which is a subset of what his opponent knows, which I'll refer to as redundant information). I focus on ¯rst-price auctions, in part because in this setting, the second-price auction has multiple equilibria. (However, my results all generalize to convex combinations between ¯rst- and second-price auctions, called \hybrid auctions," where the winner pays ²b1 + (1 ¡ ²)b2 for any ² 2 (0; 1]. For ² > 0, this auction has a unique equilibrium. If we take the limit of the equilibrium strategies as ² ! 0, this gives us an equilibrium of the second-price auction; if we assume that's the equilibrium that's played, then the results generalize to second-price auctions as well.) Let Si be the set of signals bidder i observes. First result: 2 Lemma 1. Let S1 and S2 be common knowledge (the bidders know which signals their opponents know), and let S1 ½ fX; Y g and S2 ½ fZ; W g. Let 0 ti = E(Viji s information) and Fti its probability distribution. Then ² Like in the drainage tract model, the probability distributions of b1 and b2 are identical ² Given type ti, bidder i wins with probability Fti (ti), and gets expected payo® Z ti Fti (s)ds 0 ¡1 To see why, let Gj be the distribution of bidder j's bids, and tj(b) = bj (b) the type of bidder j who bids b. Then given type ti and bid b, bidder i gets Z b ui(ti; b) = (ti + tj(s) ¡ b) dGj(s) 0 Di®erentiating with respect to b gives Z @ b ui(ti; b) = (ti + tj(b) ¡ b) gj(b) ¡ dGj(s) @b 0 Plugging in ti = ti(b) and setting this equal to 0 (equilibrium conditions) imply the ¯rst-order condition 1 g (b) = j ti(b) + tj(b) ¡ b Gj(b) Since the left-hand side does not depend on i, we get g (b) g (b) j = i Gj(b) Gi(b) which implies Gi(b) = Gj(b), so the bid distributions match. Once Gi(b) = Gj(b), we know that Pr(i winsjti) = Pr(bj(tj) < bi(ti)) = Gj(bi(ti)) = Gi(bi(ti)) = Pr(bi < bi(ti)) = Fti (ti) More importantly, since Z b ui(ti; b) = (ti + tj(s) ¡ b) dGj(s) 0 we know that Z @ b ui(ti; b) = dGj(s) = Gj(b) @ti 0 so, plugging in b = bi(ti) and applying the envelope theorem, Z ti ui(ti; bi(ti)) = Fti (s)ds 0 This lemma leads pretty directly to the two main results of the paper: 3 Theorem 1. Let S1 = fXg and S2 = fZ; W g. 1. Bidder 1 gains more from learning Y openly than secretly; and this holds for every realization (x; y) of (X; Y ) 2. Bidder 1 gains more from learning Z secretly; this holds in expectation over (X; Z), but not necessarily at every realization We'll prove the second part ¯rst. Let T = E(V jX), F its distribution, and t its realization. X R 1 X X tX Knowing only X, bidder 1's expected payo® is 0 FX (s)ds. Now suppose bidder 1 learns Z openly. Then the realization of Z is common knowledge, X is bidder 1's private information, and W is bidder 2's private information. But then Lemma 1 still R tX holds, and bidder 1's expected payo® is 0 FX (s)ds { the same as before he knew Z! It's easy to show that under very general conditions, knowing Z secretly is strictly better than not knowing it; so in expectation, bidder 1 strictly prefers to learn Z secretly. However, this is an ex-ante result; in the paper, I give a simple example where for some real- izations (x; z), bidder 1 would prefer to have learned z publicly. On to the ¯rst result. Let TXY = E(V1jX; Y ), FXY its distribution, and tXY its realization. Now, tX = EY jX=xE(V1jX = x; Y = y) = EY jX=xtXY so for a given X, tXY ¡ tX is a random variable with zero mean; which means that tXY is a mean- preserving spread around tX , or FX second-order stochastically dominates FXY . Which means that for any k, Z k Z k FX (s)ds · FXY (s)ds 0 0 Now, when 1 learns Y publicly, it's common knowledge that S = fX; Y g and S = fZ; W g, so R 1 2 tXY lemma 1 holds, with t1 = tXY ; so bidder 1's expected payo® is 0 FXY (s)ds. What if 1 learns Y secretly? When we ¯gured out 1's equilibrium strategy when he only knew X, he was maximizing his expected payo® given his estimate of E(V1) and bidder 2's equilibrium bid strategy.
Recommended publications
  • Robust Market Design: Information and Computation
    ROBUST MARKET DESIGN: INFORMATION AND COMPUTATION A DISSERTATION SUBMITTED TO THE DEPARTMENT OF COMPUTER SCIENCE AND THE COMMITTEE ON GRADUATE STUDIES OF STANFORD UNIVERSITY IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Inbal Talgam-Cohen December 2015 Abstract A fundamental problem in economics is how to allocate precious and scarce resources, such as radio spectrum or the attention of online consumers, to the benefit of society. The vibrant research area of market design, recognized by the 2012 Nobel Prize in economics, aims to develop an engineering science of allocation mechanisms based on sound theoretical foundations. Two central assumptions are at the heart of much of the classic theory on resource allocation: the common knowledge and substitutability assumptions. Relaxing these is a prerequisite for many real-life applications, but involves significant informational and computational challenges. The starting point of this dissertation is that the computational paradigm offers an ideal toolbox for overcoming these challenges in order to achieve a robust and applicable theory of market design. We use tools and techniques from combinatorial optimization, randomized algo- rithms and computational complexity to make contributions on both the informa- tional and computational fronts: 1. We design simple mechanisms for maximizing seller revenue that do not rely on common knowledge of buyers' willingness to pay. First we show that across many different markets { including notoriously challenging ones in which the goods are heterogeneous { the optimal revenue benchmark can be surpassed or approximated by adding buyers or limiting supplies, and then applying the standard Vickrey (second-price) mechanism. We also show how, by removing the common knowledge assumption, the classic theory of revenue maximiza- tion expands to encompass the realistic but complex case in which buyers are interdependent in their willingness to pay.
    [Show full text]
  • Foreclosure Auctions∗
    Foreclosure Auctions∗ Andras Niedermayery Artyom Shneyerovz Pai Xux This Draft: February 11, 2016 Abstract We develop a novel theory of real estate foreclosure auctions, which have the special feature that the lender acts as a seller for low and as a buyer for high prices. The theory yields several empirically testable predictions concerning the strategic behavior of the agents when the seller has an informational advantage. Using novel data from Palm Beach County (FL, US), we find evidence of asymmetric information, with the lender being the informed party. Moreover, the data are consistent with moral hazard in mortgage securitization: banks collect less information about the value of the mortgage collateral. Keywords: foreclosure auctions, asymmetric information, bunching, discontinuous strategies, securitization JEL Codes: C72, D44, D82, G21 ∗We thank Matt Backus, Brent Hickman, Tanjim Hossain, Matthias Lang, Philipp Schmidt-Dengler, Hidenori Takahashi, Stefan Terstiege, Thomas Tr¨oger,Ernst-Ludwig von Thadden, Lixin Ye and participants of IIOC 2014 in Chicago, the 2014 Conference on \Auctions, Competition, Regulation and Public Policy" in Lancaster, EARIE 2014 in Milan, MaCCI IO Day 2014 in Mannheim, SFB TR 15 Workshop 2015 in Bonn, the 2015 MaCCI Summer Institute in Erfstadt, the Econometric Society World Congress 2015 in Montreal, the EEA Meeting 2015 in Mannheim, seminars at the Universities of Konstanz, Mannheim, Melbourne, Toronto, the Paris School of Economics, Concordia University, and WHU (Otto Bensheim School of Management) for helpful comments. The first author acknowledges financial support from the Deutsche Forschungsgemeinschaft through SFB-TR 15. yEconomics Department, University of Mannheim, L7, 3-5, D-68131 Mannheim, Germany.
    [Show full text]
  • Auction Theory
    Auction Theory Jonathan Levin October 2004 Our next topic is auctions. Our objective will be to cover a few of the main ideas and highlights. Auction theory can be approached from different angles – from the perspective of game theory (auctions are bayesian games of incomplete information), contract or mechanism design theory (auctions are allocation mechanisms), market microstructure (auctions are models of price formation), as well as in the context of different applications (procure- ment, patent licensing, public finance, etc.). We’re going to take a relatively game-theoretic approach, but some of this richness should be evident. 1 The Independent Private Value (IPV) Model 1.1 A Model The basic auction environment consists of: Bidders i =1,...,n • Oneobjecttobesold • Bidder i observes a “signal” Si F ( ), with typical realization si • [s, s], and assume F is continuous.∼ · ∈ Bidders’ signals S1,...,Sn are independent. • Bidder i’s value vi(si)=si. • Given this basic set-up, specifying a set of auction rules will give rise to a game between the bidders. Before going on, observe two features of the model that turn out to be important. First, bidder i’s information (her signal) is independent of bidder j’s information. Second, bidder i’s value is independent of bidder j’s information – so bidder j’s information is private in the sense that it doesn’t affect anyone else’s valuation. 1 1.2 Vickrey (Second-Price) Auction In a Vickrey, or second price, auction, bidders are asked to submit sealed bids b1,...,bn. The bidder who submits the highest bid is awarded the object, and pays the amount of the second highest bid.
    [Show full text]
  • AUCTIONS an Introduction
    AUCTIONS An Introduction y Elmar Wolfstetter April Humb oldtUniversitat zu Berlin Institut f Wirtschaftstheorie I Wirtschaftswissenschaftliche Fakultat Spandauerstr Berlin Germany email wolfwiwihub erlinde Abstract This is a fairly detailed review of auction theory It b egins with basic results on private value auctions with particular emphasis on the generality and limitations of the revenue equivalence of a large class of distinct auction rules The basic framework is then gradually mo died to admit for example risk aversion a minimum price entry fees and other xed costs of bidding multiunit auctions and bidder collusion There follows an intro duction to the theory of optimal auctions and to common value auctions and the asso ciated winners curse problem It closes with a sample of applications of auction theory in economics such as the regulation of natural monop olies the theory of oligop oly and the government securities market Diese Arb eit ist im Sonderforschungsb ereich Quantikation und Simulation Okonomischer Prozesse Humb oldtUniversitat zu Berlin entstanden und wurde auf seine Veranlassung unter Verwendung der ihm von der Deutschen Forschungsgemeinschaft zur Verfugung gestellten Mittel gedruckt y Comments byFriedel Bolle UweDulleck Peter Kuhbier Michael Landsb erger Wolfgang Leininger Georg Merdian and in particular by Dieter Nautz are gratefully acknowledged Contents Intro duction Private value auctions Some basic results on Dutch and English auctions Revenue equivalence theorem The case of uniformly
    [Show full text]
  • Is the `Linkage Principle' Valid?: Evidence from the Field
    Center for Economic Institutions Working Paper Series No. 2010-4 “Is the ’Linkage Principle’ Valid?: Evidence from the Field” Sung-Jin Cho, Harry J. Paarsch and John Rust November 2010 Center for Economic Institutions Working Paper Series Institute of Economic Research Hitotsubashi University 2-1 Naka, Kunitachi, Tokyo, 186-8603 JAPAN http://cei.ier.hit-u.ac.jp/English/index.html Tel:+81-42-580-8405/Fax:+81-42-580-8333 Paper for Discussion: first draft, 19 December 2009; this draft, November 27, 2010. IS THE `LINKAGE PRINCIPLE' VALID?: EVIDENCE FROM THE FIELD BY SUNG-JIN CHO, HARRY J. PAARSCH, AND JOHN RUST Seoul National University, University of Melbourne, and University of Maryland We present field evidence involving experienced bidders that supports the link- age principle—specifically, the prediction that in affiliated-values auction environments the expected revenues generated at open-outcry, ascending-bid (English) auctions are higher than those under other auction formats that reveal less information to partic- ipants. Using field data from a large seller of automobiles which experimented with different selling formats, we find that the seller’s average revenues were significantly higher under an English auction than under a dynamic Internet auction that revealed far less information to bidders. 1. Introduction and Motivation. In an influential and classic paper, Milgrom and Weber [1982] de- rived a powerful result, and coined the term linkage principle to describe it. Simply put, in auction environ- ments having affiliated values, the linkage principle states that a seller can expect to increase revenues by providing more information to bidders, both before and during the auction.
    [Show full text]
  • Bidding Strategy and Auction Design
    16 ■ Bidding Strategy and Auction Design UCTIONS AS MECHANISMS for selling goods and services date back to ancient Greece and Rome, where slaves and wives were commonly bought and sold at well-known public auction sites. Although the auction waned as a sales mechanism for several centuries after the fall of the Roman Em- pire,A it regained popularity in eighteenth-century Britain and has been a com- mon, if not ubiquitous, method of commerce since that time. Many thousands of people now make purchases at online auctions every day, and some may buy other items by way of mechanisms that are not even recognized as auctions. Despite this long history, the first formal analysis of auctions dates only to 1961 and the path-breaking work of Nobel Prize winner William Vickrey. In the decades that followed, economists have devoted considerable energy to devel- oping a better understanding of sales by auction, from the standpoint of both buyers (bidding strategy) and sellers (auction design). We cover both topics and provide a primer on auction rules and environments in this chapter. Technically, the term “auction” refers to any transaction where the final price of the object for sale is arrived at by way of competitive bidding. Many dif- ferent types of transactions fit this description. For example, the historic Filene’s Basement department store in Boston used a clever pricing strategy to keep cus- tomers coming back for more: it reduced the prices on items remaining on the racks successively each week until either the goods were purchased or the price got so low that it donated the items to charity.
    [Show full text]
  • On Framework and Hybrid Auction Approach to the Spectrum
    On Framework and Hybrid Auction Approach to the Spectrum Licensing Procedure Devansh Dikshit Y. Narahari Electronic Commerce Laboratory, Dept. of Computer Science and Automation, Indian Institute Science, Bangalore, India. Email: {devansh},{hari}@csa.iisc.ernet.in November 13, 2018 Abstract few years, many private parties have entered in the field of telecommunications. And as expected they require a slice Inspired by the recent developments in the field of Spec- of spectrum for that purpose. This also provides a wonder- trum Auctions, we have tried to provide a comprehensive ful opportunityfor the governmentas there is useable spec- framework for the complete procedure of Spectrum trum which is left unused with the government, with only Licensing. We have identified the various issues the a fraction of it being used for military and civil purposes Governments need to decide upon while designing the by the governments. The amount of this spectrum is usu- licensing procedure and what are the various options ally scarce hence the greater demand-supply gap. Along available in each issue. We also provide an in depth study with generating revenues, privatization of spectrum will of how each of this options impact the overall procedure also lead to a faster pace of developmentby the private par- along with theoretical and practical results from the past. ties which may not be always possible to do by the govern- Lastly we argue as to how we can combine the positives ment. This has lead to the sale/licensing of the spectrums two most widely used Spectrum Auctions mechanisms by various countries across the globe, using methods like into the Hybrid Multiple Round Auction mechanism being lotteries, auctions, tenders etc.
    [Show full text]
  • Competitive Bidding in Auctions with Private and Common Values
    TI 2000-044/1 Tinbergen Institute Discussion Paper Competitive Bidding in Auctions with Private and Common Values Jacob K. Goeree Theo Offerman Tinbergen Institute The Tinbergen Institute is the institute for economic research of the Erasmus Universiteit Rotterdam, Universiteit van Amsterdam and Vrije Universiteit Amsterdam. Tinbergen Institute Amsterdam Keizersgracht 482 1017 EG Amsterdam The Netherlands Tel.: +31.(0)20.5513500 Fax: +31.(0)20.5513555 Tinbergen Institute Rotterdam Burg. Oudlaan 50 3062 PA Rotterdam The Netherlands Tel.: +31.(0)10.4088900 Fax: +31.(0)10.4089031 Most TI discussion papers can be downloaded at http://www.tinbergen.nl Competitive Bidding in Auctions with Private and Common Values Jacob K. Goeree and Theo Offerman* November 1999 ABSTRACT The objects for sale in most auctions display both private and common value characteristics. This salient feature of many real-world auctions has not yet been incorporated into a strategic analysis of equilibrium bidding behavior. This paper reports such an analysis in the context of a stylized model in which bidders receive a private value signal and an independent common value signal. We show that more uncertainty about the common value results in lower efficiency and higher profits for the winning bidder. Information provided by the auctioneer decreases uncertainty, which improves efficiency and increases the seller’s revenue. These positive effects of public information disclosure are stronger the more precise the information. Efficiency and revenues are also higher when more bidders enter the auction. Since our model nests both the private and common value case it may lead to an improved specification of empirical models of auctions.
    [Show full text]
  • Competition in Bidding Markets 2006
    Competition in Bidding Markets 2006 The OECD Competition Committee debated competition in bidding markets in October 2006. This document includes an executive summary and the documents from the meeting: an analytical note by Ms. Sally Van Siclen for the OECD and written submissions: Czech Republic, the European Commission, Germany, Hungary, Indonesia, Japan, Korea, Mexico, Netherlands, New Zealand, Romania, South Africa, Switzerland, Turkey, the United Kingdom, the United States as well as papers from BIAC and Professor Paul Klemperer. An aide-memoire of the discussion is also included. Competition authorities become interested in auctions by a number of routes. In competition advocacy, they may advise other parts of government on how to design auctions in order to improve their efficiency—the degree of competition. They may evaluate mergers and agreements between firms that operate in auction markets. And they may be concerned with collusion and abuse of a dominant position in auctions. Because their formal rules reduce “noise” and make communication among rivals easier, auctions can promote collusion, compared with ordinary “posted-price” markets. But an auction can be designed to reduce collusion or concerted practices or to promote participation. Thus, the design of an auction can be the object of lobbying pressure. Auctioneers can also behave strategically, choosing auction formats or practices that favour competition. Two fundamental prescriptions for effective auction design follow from the theoretical literature: Induce bidders
    [Show full text]
  • Countering the Winner's Curse: Optimal Auction Design in A
    COUNTERING THE WINNER’S CURSE: OPTIMAL AUCTION DESIGN IN A COMMON VALUE MODEL By Dirk Bergemann, Benjamin Brooks, and Stephen Morris November 2018 COWLES FOUNDATION DISCUSSION PAPER NO. 2147 COWLES FOUNDATION FOR RESEARCH IN ECONOMICS YALE UNIVERSITY Box 208281 New Haven, Connecticut 06520-8281 http://cowles.yale.edu/ Countering the Winner’s Curse: Optimal Auction Design in a Common Value Model∗ Dirk Bergemann Benjamin Brooks Stephen Morris November 16, 2018 Abstract We characterize revenue maximizing mechanisms in a common value environment where the value of the object is equal to the highest of bidders’ independent signals. The optimal mechanism exhibits either neutral selection, wherein the object is randomly allocated at a price that all bidders are willing to pay, or advantageous selection, wherein the object is allocated with higher probability to bidders with lower signals. If neutral selection is optimal, then the object is sold with probability one by a deterministic posted price. If advantageous selection is optimal, the object is sold with probability less than one at a random price. By contrast, standard auctions that allocate to the bidder with the highest signal (e.g., the first-price, second-price or English auctions) deliver lower revenue because of the adverse selection generated by the allocation rule: if a bidder wins the good, then he revises his expectation of its value downward. We further show that the posted price mechanism is optimal among those mech- anisms that always allocate the good. A sufficient condition for the posted price to be optimal among all mechanisms is that there is at least one potential bidder who is omitted from the auction.
    [Show full text]
  • An Empirical Perspective on Auctions
    THE CENTER FOR THE STUDY OF INDUSTRIAL ORGANIZATION AT NORTHWESTERN UNIVERSITY Working Paper #0078 An Empirical Perspective on Auctions By Ken Hendricks University of Texas and Robert H. Porter* Northwestern University First Draft: April, 2006 This Draft: June, 2006 * Forthcoming in the Handbook of Industrial Organization (Vol. III), edited by M. Armstrong and R. Porter. We are grateful to Mark Armstrong, Phil Haile, Jakub Kastl, Paul Klemperer and Harry Paarsch for helpful comments. Visit the CSIO website at: www.csio.econ.northwestern.edu. E-mail us at: [email protected]. Abstract We describe the economics literature on auction markets, with an emphasis on the connection between theory, empirical practice, and public policy, and a discussion of out- standing issues. We describe some basic concepts, to highlight some strengths and weaknesses of the literature, and so indicate where further research may be warranted. We discuss identification and estimation issues, with an emphasis on the connection between theory and empirical practice. We also discuss both structural and reduced form empirical approaches. Keywords: auctions, bidding, identification, estimation, collusion, bid rigging. Contents 1 Introduction 4 2 Model and Notation 8 3 Structural Analysis of Second-Price Auctions 12 3.1 Theory . 12 3.2 Estimation . 17 3.3 Identi…cation . 24 4 Structural Analysis of First Price Auctions 27 4.1 Theory . 28 4.2 Estimation . 30 4.3 Identi…cation . 36 5 Tests of Private Versus Common Values 38 6 Tests of the Theory 43 6.1 Pure Common Value Auctions . 44 6.1.1 The Asymmetric Case . 46 6.1.2 The Symmetric Case .
    [Show full text]
  • Optimal and Near-Optimal Mechanism Design with Interdependent Values
    Proceedings Article Optimal and Near-Optimal Mechanism Design with Interdependent Values TIM ROUGHGARDEN, Stanford University INBAL TALGAM-COHEN, Stanford University We study optimal and approximately-optimal mechanism design questions in the interdependent values model, which generalizes the standard setting of independent and private values. We focus our attention on ex post incentive compatible and individually rational mechanisms, and develop an analog of Myerson's optimal auction theory that applies to many interdependent settings of interest. We demonstrate two ap- plications for specific interdependent settings: First, a parallel result to the well-known optimality of the second-price auction with reserve for i.i.d. bidders, where the English auction replaces the second-price one. Second, we identify good prior-independent auctions | auctions with near-optimal expected revenue across a wide range of priors | for certain interdependent value settings. Categories and Subject Descriptors: [Theory of Computation]: Algorithmic game theory and mechanism design Additional Key Words and Phrases: interdependence; optimal auctions; prior-independence 1. INTRODUCTION The subject of this paper is optimal and approximately-optimal mechanism design, where bidders have interdependent values, and the mechanism has ex post incentive compatibility and individual rationality guarantees. Economic research on auctions has explored different valuation models over the past decades, which can roughly be divided into private versus interdependent values (for exam- ple, see [Krishna 2010, Chapters 2-5] versus [Krishna 2010, Chapters 6-10]). The more nacent research effort in theoretical computer science has focused largely on the restricted setting of independent private values, recently also venturing into the realm of correlated private values [Papadimitriou and Pierrakos 2011; Dobzinski et al.
    [Show full text]