早稲田木曜セミナー　（早稲田大学現代政治経済研究所船木部会研究会)

• 「数理経済学、社会的選択論、ゲーム理論、実験経済学」を テーマとしたセミナーです．
• 毎月2,3回，原則的に木曜の16時30分から18時に 早稲田大学早稲田キャンパス1号館4階401教室で開催されます．
• 興味を持たれた方は日程等をご確認の上，直接会場にお越し下さい．事前連絡等は不要です．
• スケジュール（予定）は下記をご参照下さい．
• 早稲田キャンパス1号館の位置はこちらをご覧ください。
• お問い合わせや報告の希望等は　waseda.economics.seminer@gmail.com　までご連絡下さい．

近日開催セミナー詳細

· 2012年5月17日(木）　16時30分から18時00分

· 場所：早稲田大学早稲田キャンパス1号館4階1-401教室

· 報告者　星野匡郎（東京工業大学大学院情報理工学系研究科助手）

· 題目：Estimation of Semiparametric Binary Choice Models with Missing Response Data

· 概要：This study investigates identification of parameters in the semiparametric binary choice models when there are nonignorable nonresponses. We propose an estimation procedure for the identified set of parameters based on the special regressor approach, Lewbel (2000). We show that the estimator for the identified set is consistent in the Hausdorff metric. To demonstrate the availability of the proposed methodology, we present an empirical case study consisting of an economic valuation of a landscape with a dichotomous choice contingent valuation.

日程	報告者（所属）	報告タイトル
4月26日（木）	Noemí Navarro （Université de Sherbrooke）	How to Add Apples and Pears: Non-Symmetric Nash Bargaining and the Generalized Joint Surplus
5月17日(木)	星野匡郎（東京工業大学）	Estimation of Semiparametric Binary Choice Models with Missing Response Data

終了したセミナー

· 2012年4月16日(木）　16時30分から18時00分

· 場所：早稲田大学早稲田キャンパス1号館4階1-401教室

· 報告者Noemí Navarro（Université de Sherbrooke）

· 題目： "How to Add Apples and Pears: Non-Symmetric Nash Bargaining and the Generalized Joint Surplus" (joint with Samuel Danthine)

· 概要：We generalize the equivalence of the non-symmetric Nash bargaining solution and the linear division of the joint surplus when bargainers use different utility scales. This equivalence in the general case requires the surplus each agent receives to be expressed in compatible, or comparable, units. This result is valid in the case of bargaining over multiple-issues. Our conclusions have important implications for comparative static exercises and calibrated work. For example, when comparing the joint surplus of economies with different preferences, it is crucial to lay out the surplus in terms of one utility unit or the other. On the other hand, while it is necessary to transform the units when expressing the non-symmetric Nash bargaining solution as a share of the joint surplus, it is not necessary to perform a unit transformation when maximizing directly the generalized Nash product. Finally, we discuss the requirements on the curvatures of the agents’ utility functions, or, in other words, on the bargainers’ attitudes towards risk.

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終了したセミナー

日程	報告者（所属）	報告タイトル
10月3日（月）	Ron Harstad　氏 （Univ. of Missour）	Political Economy Field Experiments Become Possible
10月13日（木）	Dimitry Rtischev　氏 （学習院大学）	Evolution of preferences, mindsight, and cooperation
10月20日（木）	石川竜一郎　氏 （筑波大学）	ヴィクセル型取引ネットワークにおけるエッジワース競争の分析
11月24日（木）	宮城島 要　氏 (早稲田大学)	Education inequality among different social groups
12月15日(木)	田中　知美氏 (アリゾナ州立大学)	Does Marriage Work as a Savings Commitment Device? : Experimental　Evidence from Vietnam
1月19日(木)	土橋　俊寛　氏 (大東文化大学)	Sequential Internet auctions with different ending rules
3月1日（木）	和田良子氏（敬愛大学）	A Factor Analysis of Transaction Costs in Time Preference Experiments
3月1日（木）	鍵原理人氏 （福岡大学経済学部）	囚人のジレンマにおける協力の選択に対する非協力探知型情報構造の効果についての実験的研究

• 日時：5月26日（木）16時30分から18時00分
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者：原　千秋　氏（京都大学経済研究所）
• 題目：Heterogeneous impatience and dynamic inconsistency
• 概要：It has been well known in the literature that the representative consumer of individual consumers having heterogeneous impatience has decreasing impatience, and, hence, is dynamically inconsistent. However, it has not been investigated whether any sort of higher degree of heterogeneity leads to any sort of higher degree of dynamic inconsistency. In this paper, we use the cumulant-generating function of the wealth-weighted distribution of subjective discount rates and the definition by Prelec (2004) of the measure of dynamic inconsistency, and show that the more convex the cumulant-generating function is, the more dynamically inconsistent the representative consumer is.

• 日時：6月2日（木）16時30分から18時00分
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者：武岡　則男　氏（横浜国立大学）
• 題目：Stochastic Endogenous Time Preference
• 概要：Preference for flexibility arises inherently in sequential decision making. However, a majority of the literature accommodating this behaviorhas limitations to capture changing preference for flexibility across time. This study incorporates the histories of past consumption into an infinite horizon extension of Dekel, Lipman, and Rustichini (2001), and models a decision maker who may change preference for flexibility according to her histories of past consumption. In particular, we focus on a decision maker having preference for flexibility because she is uncertain about future time preference or discount factors, and such uncertainty evolves according to histories of past consumption. Within our framework, we can compare attitude toward flexibility across different histories, in terms of a trade-off between earlier but smaller rewards and later but larger rewards. This comparison characterizes a property of the representation in which the decision maker's belief about future discount factors at some history is greater than her belief at another history in the increasing convex and concave stochastic orders. That is, the former belief is interpreted as being more patient than the latter in a stochastic sense.

• 日時：6月16日（木）16時30分から18時00分
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者：篠　潤之介　氏（京都大学経済研究所）
• 題目：A Positive Theory of Fixed-Rate Funds-Supplying Operations in an Accommodative Financial Environment
• 概要：This paper studies bidding behaviors in ?xed-rate funds-supplying auctions using a simple game-theoretic model. While the existing literature argues that such auction schemes are vulnerable to the overbidding problem, the bid-to-cover ratio for the Bank of Japan’s current ?xed-rate operations has remained stable. We modify the stylized repo game by incorporating the current framework of ?xed-rate funds-supplying auctions operated by the Bank of Japan and the accommodative ?nancial environment recently experienced in Japan. It is shown that any stable bid-to-cover ratios other than either undersubscription or overbidding can be supported by an equilibrium in the modi?ed game.

• 日時：7月14日（木）16時30分から18時00分
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者：星野　匡郎　氏（東京工業大学）
• 題目：Quantile regression in spatial autoregressive semivarying-coefficient models
• 概要：This study develops a quantile regression estimator for the spatial autoregressive semivarying-coefficient model. Semivarying-coefficient models assume that some of the regression coefficients vary with some known variables, while other coefficients are fixed to be constant. The proposed model is general in that it encompasses both the standard spatial autoregressive model and the geographically weighted regression model. For model stimation, we use a two-step GMM approach. We establish the asymptotic properties for the estimator including consistency and asymptotic normality. Under certain conditions, it is shown that the constant coefficient estimator is root-n-consistent, and that the functional coefficient estimator has the oracle property. The finite sample properties of the estimator are assessed using a set of Monte Carlo experiments. Finally, the proposed estimator is applied to the well-known Boston housing data of Harrison and Rubinfeld (1978). The estimated coefficients including the spatial autocorrelation parameter show a certain degree of heterogeneity at different quantiles and different locations.
  
  
• 日時：7月28日（木）16時30分から18時00分
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者：大垣　昌夫　氏（慶應義塾大学）
• 題目：Cultures, Worldviews, and Intergenerational Altruism
• 概要：This paper presents empirical evidence concerning e
  ects of cultural differences on parents' attitudes toward children from unique U.S. and Japanese survey data. These data sets have been collected by Osaka University, and contain questions concerning worldviews and religions,　hypothetical questions about parental behavior, and questions about socioeconomic variables. The data show that U.S. parents tend to be tougher than Japanese parents toward young children. Our evidence suggests that contents of worldview beliefs held by parents affect parents' attitudes toward children. Our empirical evidence also indicates that people who are con
  dent about issues related to worldviews tend to show tough attitudes toward their children. Because U.S. parents are much more con
  dent than Japanese parents in worldview issues on the average, this cultural di
  erence helps explain a substantial portion of the difference in parental attitudes between U.S. and Japanese parents.

· 日時：2011年10月3日(月）　16時30分から18時00分

· 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室

· 報告者：Ron Harstad, (Univ. of Missouri)

· 題目： Political Economy Field Experiments Become Possible.

· 概要：An important part of a field experiment measuring the effectiveness of a　proposed policy (social, environmental, public god provision, etc.) would be　to gather information about its allocative efficiency. Efficiency measures　are a standard part of lab experiments in economics. The talk will　explain how efficiency is measured in the lab, why that method　cannot be used in the field, and propose a new definition and new　method that would allow observing allocative efficiency in the field.　Initial demonstrations of the methodology will be discussed.

· 日時：2011年10月13日(木）　16時30分から18時00分

· 場所：早稲田大学早稲田キャンパス1号館4階1-401教室

· 報告者：Dimitry Rtischev　氏 (学習院大学)

· 題目： Evolution of preferences, mindsight, and cooperation

· 概要：Even in anonymous one-shot interactions humans often do not behave　as if each is maximizing his own payoff while assuming others do the same. This propensity to sidestep the logic of Nash equilibrium and the common knowledge of rationality can lead to more cooperation and economically better outcomes in social dilemma situations. But can such a propensity evolve among self-interested agents? Taking hints from evolutionary psychology and interpersonal neurobiology, we focus on mindsight, the capability to perceive how another person is disposed to behave. We model the evolution of preferences and mindsight in a population of self-interested agents living in an environment that requires team production for survival and reproduction. We show that if agents are randomly matched to play a two-agent team production game, preferences and mindsight may evolve, allowing agents to partially overcome the social dilemma within each dyad and produce significantly more than in Nash equilibrium, but not as much as under full cooperation.

· 日時：2011年10月20日(木）　16時30分から18時00分

· 場所：早稲田大学早稲田キャンパス1号館4階1-401教室

· 報告者：石川竜一郎　氏 (筑波大学)

· 題目： ヴィクセル型取引ネットワークにおけるエッジワース競争の分析

· 概要：本稿では、経済取引を行う相手がヴィクセル的三角形のネットワーク構造で制約された取引の分析例を示す。この分析は、取引ネットワークに参加する経済主体の人数で分類して進められる。取引主体の人数で分類した分析を通じて、その増加が競争的取引にどのように影響を及ぼすかを明示的に扱う。特に本稿では、経済取引のコア配分の集合の包含関係を通じて競争的取引への影響を検証する。

· 日時：2011年12月15日(木）　16時30分から18時00分

· 場所：早稲田大学早稲田キャンパス1号館4階1-401教室

· 報告者：田中　知美　氏 　(Arizona State University)

· 題目： Does Marriage Work as a Savings Commitment Device? :Experimental Evidence from Vietnam

· 概要：We conducted a time discounting experiment with married couples, and examined how time　preferences, particularly time inconsistency, affect　intrahousehold financial decision making. Our experimental results suggest people are more patient when they make decisions jointly with their spouses. The analysis of survey data shows time-inconsistent individuals turn over smaller percentages of their earnings to their spouses. Time-inconsistent husbands are more likely to keepcash within households compared with time-consistent husbands. Time-inconsistent individuals are given smaller amounts of allowances, but they tend to conceal money to compensate. In addition, time-inconsistent subjects choose not to ask their spouses to keep their experimentalearnings and save it for them in the experiment. This study shows marriage does not function (or may counteract) as a savings commitment device, especially for time-inconsistent individuals. This implies households need external savings commitment devices such as ROSCAs to protect money from spouses who have hyperbolic preferences.

· 日時：2012年1月19日(木）　16時30分から18時00分

· 場所：早稲田大学早稲田キャンパス1号館4階1-401教室

· 報告者：土橋　俊寛　氏 　(大東文化大学)

· 題目： Sequential Internet auctions with different ending rules

· 概要：Two ending rules, a soft close and a hard close, exist in Internet　auctions. The hard close auction involves a fixed deadline, while the　deadline in the soft close auction may be extended if at least one bid　is submitted in the final few minutes. Thus, the soft close allows　buyers to submit ofter observing the opponent’s bids even in the last　minutes. Ending rules change both the seller’s and the buyers’　strategies. In a sequential auction with the soft close, buyers have a　stronger incentive to wait for low reserve prices in the future, and a　seller chooses lower reserve prices.

· 2012年3月1日(木）　�@16時00分から17時00分 �A17時00分から18時00分

· 場所：早稲田大学早稲田キャンパス1号館4階1-401教室

· 報告者�@：和田良子氏（敬愛大学）

· 題目： A Factor Analysis of Transaction Costs in Time Preference Experiments

· 概要：実験により計測された時間選好率が高すぎることは良く知られているが，我々の研究は，時間選好率の計測結果に含まれるバイアスを取り除いて，純粋な時間選好に近いものを計測する試みである．バイアスの要因は時間選好率を測る実験の手法に共通かつ不可避なものである．確実な今すぐの報酬の受けとりと等価な将来報酬を回答させるとき，実験者への報酬の預託コストと後日報酬を受け取るコストがあると考えられる．この2つについて，1回のみの報酬受け取りによる先行研究では区別できなかったが，我々は報酬受取りを2回にしたことで，各要素の分離が可能になり，その結果，より低い時間選好率を得た．

· 報告者�A：鍵原理人氏（福岡大学経済学部）

· 題目：囚人のジレンマにおける協力の選択に対する非協力探知型情報構造の効果についての実験的研究

· 概要：囚人のジレンマの利得構造の下で，プレイヤーの先手/後手の手番はランダムに決められ，先手が非協力行動を選択する場合にのみその行動が後手によって観察されるとする．このゲームと通常の囚人のジレンマとの相違は情報構造の違いに帰着する．情報構造がこのように修正された囚人のジレンマを非協力探知型情報構造を持つ囚人のジレンマと呼ぶ．非協力探知型情報構造を持つ囚人のジレンマには，利得構造がある一定の条件を満たすとき，双方のプレイヤーが協力的戦略を選択して協力行動がプレイされるナッシュ均衡が存在する．本研究の目的は，このゲームの協力的戦略の選択比率が，通常の囚人のジレンマの協力的戦略（協力行動）の選択比率に比べて，高いか否かを実験によって検証することにある．実験の結果，理論が示唆する範囲の利得構造において，協力的戦略の選択比率は非協力探知型情報構造を持つ囚人のジレンマで高まることが示される．

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2010年度後期スケジュール

日程	報告者（所属）	報告タイトル
10月15日（金）	Robert Veszteg　氏 （早稲田大学）	Some experimental results on decentralized matching markets
10月25日（月）	William Thomson　氏 （University of Rochester）	On the manipulability of allocation rules through endowment augmentation
11月5日（金）	竹澤 正哲　氏 （上智大学）	Do people use the second-order information for forming reputation?: Memory-based indirect reciprocity
11月19日（金）	田中 知美　氏 （アリゾナ州立大学）	Committing the Uncommitted: Rosca as a Saving Commitment Device for Sophisticated Hyperbolic Discounters
12月10日（金）	Marc Willinger　氏 （University of Montpellier）	Income Redistribution and Public Good Provision: an Experiment
12月17日（金）	高宮　浩司　氏 （新潟大学）	Complexity consideration on the existence of strategy-proof social choice functions
1月14日（金）	Rene van den Brink　氏 （Free University）	Axiomatizations of a Positional Power Score and Measure for Hierarchies
1月27日（木）	Charles Noussair　氏 （Tilburg University）	Prudence, Temperance, and Demographics
2月24日（木）	Mardyla Greg　氏 （近畿大学）	Borrowing Behavior and Attitudes towards Risk and Time Experimental Approach

終了したセミナー

• 日時：10月15日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館3階310教室
• 報告者：Robert Veszteg　氏（早稲田大学）
• 題目：Some experimental results on decentralized matching markets
• 概要：TBA

• 日時：10月25日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：William Thomson　氏（University of Rochester）
• 題目：On the manipulability of allocation rules through endowment augmentation
• 概要：We formulate and study the requirement on an allocation rule that no agent should be able to benefit by artificially augmenting his endowment. This can be either through borrowing resources from the outside world, or by simply exaggerating it. We show that the Walrasian rule is not “augmentation-proof” even on standard domains. More seriously, no efficient selection from the endowments-lower-bound correspondence, or from the no-envy-in-trades correspondence, or from the egalitarian-equivalent-in-trades correspondence is augmentation-proof. These impossibilities hold even on the domain of economics with homothetic preferences, and even if the agent is constrained to borrow no more than an arbtrarily small proportion of the resources he truly owns.

• 日時：11月5日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：竹澤 正哲　氏（上智大学）
• 題目：Do people use the second-order information for forming reputation?: Memory-based indirect reciprocity
• 概要：Evolutionary game theoretical models revealed that the success of indirect reciprocity critically depends on how individuals evaluate recipients. Several strategies for forming reputation have been proposed. One major dimension categorizing the strategies is whether to use the second-order information (i.e., reputation / behavior of past recipients of current recipients) and theoretical analyses found that the information should be used for discriminating justified from unjustified defection. However, results of the experiments that investigated whether people actually use the second order information are rather mixed (Wedekind & Milinski, 2000; Milinski et al., 2001; Bolton et al., 2005; Mashima & Takahashi, 2008). In this study, we investigated the same question under a novel experimental setting where people need to store the information of the others’ past actions in their memory. Differently from the previous studies where experimenters explicitly presented both the first and second order information to participants, participants in the current study need to recall the information from their memory when they need to evaluate others’ reputation. Two hypothetical scenario experiments and one laboratory experiment revealed that, although people seem to be able remember both the behavior of the current recipient (first-order information) and the behavior of the recipient of the current recipient (second-order information), both participants judgments of reputation and actions in the repeated random-matching giving game (Bolton et al., 2005) are mostly based only on the first order information.

• 日時：11月19日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：田中 知美　氏（アリゾナ州立大学）
• 題目：Committing the Uncommitted: Rosca as a Saving Commitment Device for Sophisticated Hyperbolic Discounters
• 概要：This paper investigates whether the participation in rotating savings and credit associations (roscas), an informal financial institution-like arrangement found in many developing countries, is correlated with time discounting, risk aversion, and the level of trust and reciprocity measured in experiments. Our experimental results show people who participate in fixed roscas are less present-biased, have lower discount rates and are often aware of the self-control than those who participate in bidding roscas. The members of fixed roscas are also more trustworthy, and less prone to default. Our results suggest designing financial institutions requires some knowledge about the preferences and motives of potential participants, and preference measurement can provide insights into institutional design.

• 日時：12月10日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館3階310教室
• 報告者：Marc Willinger　氏（University of Montpellier）
• 題目：Income Redistribution and Public Good Provision: an Experiment
• 概要：We provide a new experimental investigation of the neutrality theorem of Warr (1983), who states “when a single public good is provided at positive levels by private individuals, its provision is unaffected by a redistribution of income”. Instead of comparing different income distributions across groups as Chan et al. (1996), in our experiment the total group endowment is redistributed after a 10 periods sequence. We compare an unequalizing redistribution (EI) and an equalizing redistribution (IE) to two benchmark treatments for which the 10 periods sequence is repeated, either with an equal distribution (EE) or an unequal distribution (II). The constituent game has a unique interior dominant strategy equilibrium. Our data support the neutrality theorem (after controlling for the restart effect): redistribution has no effect on the total amount of public good in any of the tested treatments. However, the analysis of individual behavior shows that “poor” subjects over-contribute with respect to their Nash-contribution, while “rich” subjects tend to play their Nash-contribution or under-contribute slightly. Furthermore, after a redistribution, subjects react asymmetrically: subjects who get poorer reduce their contribution by a larger amount than the amount of contribution added by subjects who become richer. And it is shown that the latter do not react enough to the redistribution.

• 日時：12月17日（金）15時から16時30分
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：高宮　浩司　氏（新潟大学）
• 題目：Complexity consideration on the existence of strategy-proof social choice functions
• 概要：Social choice theorists have long recognized that in models of private goods economies, strategy-proofness is sometimes incompatible with individual rationality plus Pareto efficiency, and that it is usually more or less "difficult" to prove this incompatibility. In this paper we examine this difficulty" from the viewpoint of computational complexity. We set up a simple model of private goods exchange where agents bring in and trade indivisible objects under onsumption constraints. We consider the computational problem of deciding whether for a given specification of the economy, there exists a social choice function which is rategy-proof, individually rational and Pareto efficient. We prove that (i) this is an NP-hard problem, and point out, however, that (ii) the problem becomes computationally trivial if we drop one of these three properties of the social choice function.

• 日時：1月14日（金）17時10分から18時10分
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Rene van den Brink　氏（Free University）
• 題目：Axiomatizations of a Positional Power Score and Measure for Hierarchies
• 概要：The extant literature on positional power in hierarchies is mainly restricted to the analysis of power in terms of the authority structure. This is based upon the bare positions of actors and ignores the existence of decision-making mechanisms. The few studies, which also take into account decision-making mechanisms, are 'membership-based'. In an earlier paper we demonstrated that such an approach is, in general, inappropriate. As a solution we suggested an 'action-based' approach and developed a power score and measure ascribing positional power to actors in hierarchies. In this paper we axiomatize this power score and measure and illustrate their applicability.

• 日時：1月27日（木）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者：Charles Noussair　氏（Tilburg University）
• 題目：Prudence, Temperance, and Demographics
• 概要：We study the prevalence of the higher order risk attitudes of prudence and temperance, in a large representative sample of the Dutch population, as well as in a sample of undergraduate students. Participants make pairwise choices between lotteries of the form proposed by Eeckhoudt and Schlesinger (2006). The choices in these lotteries isolate prudent from imprudent, and temperate from intemperate, behavior. We relate individuals’ risk aversion, prudence, and temperance levels to demographics and financial decisions. We observe that the majority of individuals’ decisions are consistent with risk aversion, prudence, and temperance, in both the student and the demographically representative samples. An individual’s level of prudence is predictive of his wealth, saving and borrowing behavior outside of the experiment, while his risk aversion and temperance are not. Estimates of parametric specifications of risk and prudence parameters are compared to key thresholds of theoretical models.

• 日時：2月24日（木）17時00分から18時00分
• 場所：早稲田大学早稲田キャンパス8号館5階会議議室
• 報告者：Mardyla Greg　氏（近畿大学）
• 題目：Borrowing Behavior and Attitudes towards Risk and Time Experimental Approach
• 概要：We investigate experimentally potential links between individual propensity to borrow and attitudes towards risk and time, the latter representedrespectively by risk aversion coefficient and individual discount factor. To obtain both above-mentioned measures we employ a joint elicitation procedure using a multiple price list design. We further employ a novel experimental construct akin to a consumption/financial planning setting to examine individual propensity to borrow. Straightforward cross-analysis of our participants’intrinsic attitudes towards risk and time against their exhibited borrowing behavior allows us to conclude that it is the individual discount factor and not the risk aversion coefficient that could potentially explain and predict individual borrowing. Whilst we find no correlation between diversity in risk attitudes and inclination to borrow, higher individual discount factors correlate significantly with number of loans undertaken. Moreover, this is only the case whenever depreciation rates on the available consumption bundle match individual discount rates discount factors have no predictive power if the discount rate on the value of consumption is exogenously set. From the methodological perspective, this project offers support to the technique of artificially shrinking a time-frame in a decision task in economic experiments. The consistency between individual discount factors elicited in one stage of the experiment and the decisions made in a later stage in a consumption/borrowing game based on the earlier elicited coefficients strongly indicates viability of experiments with reduced time-frames.

---

2010年度春学期スケジュール

日程	報告者（所属）	報告タイトル
4月19日（月）	戸田　学　氏 （早稲田大学）	Characterization of Stable Solutions in Matching Markets
5月17日（月）	井上朋紀　氏 （Bielefeld University）	Representation of TU games by coalition production economies
5月31日（月）	坂東桂介　氏 （東京工業大学）	Many-to-one matching markets with externalities of firms
6月14日（月）	安田洋祐　氏 （政策研究大学院大学）	学校選択制のマッチング分析：最新理論と日本の制度設計
6月21日（月）	Farhad Husseinov　氏 （Bilkent University）	Monotonic extension and its applications in the choice theory
7月26日（月）	小島武仁　氏 （Stanford University）	Improving Efficiency in Matching Markets with Regional Caps: The Case of the Japan Residency Matching Program (joint with Yuichiro Kamada)

終了したセミナー

• 日時：4月19日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：戸田　学 氏(早稲田大学）
• 題目：Characterization of Stable Solutions in Matching Markets
• 概要：TBA

• 日時：5月17日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：井上朋紀　氏（Bielefeld University）
• 題目：Representation of TU games by coalition production economies
• 概要：We prove that every transferable utility (TU) game can be generated by a coalition production economy. Given a TU game, the set of Walrasian payoff vectors of the induced coalition production economy coincides with the core of the balanced cover of the given game. Therefore, a Walrasian equilibrium for the induced coalition production economy always exists. The induced coalition production economy has one output and the same number of inputs as agents. Every input is personalized and it can be interpreted as agent's labor. In a Walrasian equilibrium, every agent is permitted to work at several firms. In a Walrasian equilibrium without double-jobbing, in contrast, every agent has to work at exactly one firm. This restricted concept of a Walrasian equilibrium enables us to discuss which coalitions are formed in an equilibrium. If the cohesive cover or the completion of a given TU game is balanced, then the no-double-jobbing restriction does not matter, i.e., there exists no difference between Walrasian payoff vectors and Walrasian payoff vectors without double-jobbing.

• 日時：5月31日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：坂東桂介　氏（東京工業大学）
• 題目：Many-to-one matching markets with externalities of firms
• 概要：We analyze a many-to-one matching market where each firm's gross profit depends not only on the workers it may hire, but also on the workers hired by the other firms. We assume that a firm and workers deviate from an outcome, keeping fixed the other agents' assignments, and define the stability concept based on the criterion. With flexible salaries, if each firm's gross profit satisfies the gross substitutes condition and the separable condition, then there exists a weakly stable outcome. With fixed salaries, the substitutability condition and order preservation for rival equivalence are a sufficient condition for the existence of a weakly stable outcome. Especially, in flexible salaries, it is difficult to ensure the existence of a weakly stable outcome without a stringent condition that a firm's marginal returns for hiring workers do not depend on how the others match.

• 日時：6月14日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：安田洋祐　氏（政策研究大学院大学）
• 題目：学校選択制のマッチング分析：最新理論と日本の制度設計
• 概要：TBA

• 日時：6月21日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Farhad Husseinov　氏（Bilkent University）
• 題目：Monotonic extension and its applications in the choice theory
• 概要：The existence of an extension of a continuous and (strictly) monotonic function defined on a closed subset of a Euclidean space that preserves these properties to the entire space is proved. These results are applied to study the choice behavior in the context of two-stage choice situation where in the first stage a menu, and in the second stage an alternative from the chosen menu is chosen.

• 日時：7月26日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：小島武仁　氏（Stanford University）
• 題目：Improving Efficiency in Matching Markets with Regional Caps: The Case of the Japan Residency Matching Program (joint with Yuichiro Kamada)
• 概要：In an attempt to increase the placement of medical residents to rural hospitals, Japanese government recently introduced ``regional caps" which, for each prefecture of the country, restrict the total number of students matched within the prefecture. This paper shows that the current mechanism with regional caps may result in avoidable inefficiency and instability and proposes a new mechanism that improves efficiency and generates stable matchings while meeting the regional caps. We find that different stable matchings can have different sets of hospitals with vacant positions, implying that the rural hospital theorem fails in our context. Thus there may be room for government to select a particular stable matching based on its welfare and distributional goals. More broadly, the paper points a direction of matching/market design theory to accommodate problems arising in practical matching problem.

---

2009年度後期スケジュール

日程	報告者（所属）	報告タイトル
10月16日（金）	Robert Veszteg　氏 （Universidad Carlos III de Madrid）	Learning and playing best response in the hide-and-seek game
11月2日（月）	グレーヴァ香子　氏 （慶応義塾大学）	Voluntarily Separable Repeated Prisoner's Dilemma with Reference Letters
11月9日（月）	Gustavo Bergantinos　氏 （University of Vigo）	※若手研究者向けセミナー The family of cost monotonic and cost additive rules in minimum costspanning tree problems
11月12日（木）	Gustavo Bergantinos　氏 （University of Vigo）	The division problem with voluntary participation
11月26日（木）	浅古泰史　氏 （日本銀行）	Partially Binding Platforms and the Advantages of Being an Extreme Candidate
11月27日（金）	加藤晋　氏 （東京大学）	Conditions for Cyclic Social Preference
12月10日（木）	海老名剛　氏 （東京工業大学）	Option Package Bundling
12月11日（金）	藤中裕二　氏 （首都大学東京）	公平分担問題におけるメカニズムデザイン
12月15日（火）	Zaifu Yang　氏 （横浜国立大学）	Constrainedly fair job assignments under minimum wages
12月17日（木）	下津克己　氏 （一橋大学）	Sequential Estimation of Dynamic Programming Models
12月21日（月）	小島武仁　氏 （Stanford University）	Implementing Random Assignments: A Generalization of the Birkhoff-von Neumann Theorem
1月30日（土）	篠潤之介　氏 （Rutgers University）	Farsighted Stable Sets in Hotelling's Location Games
2月1日（月）	Charles Noussair　氏 （Tilburg University）	※若手研究者向けセミナー Experiment Asset Markets: Bubbles and Crashes
2月5日（金）	Charles Noussair　氏 （Stanford University）	How Others Influence One’s Behavior: Investigation with fMRI Imaging
2月22日（月）	Menahem E. Yaari氏 （The Hebrew University of Jerusalem）	Justice and the Market
3月23日（火）	Bettina Klaus 氏 (ローザンヌ大学）	※若手研究者向けセミナー Recent developments in matching markets: matching with contracts (including couples markets, preference domains, and stability concepts)
3月24日（水）	Bettina Klaus 氏 (ローザンヌ大学）	※若手研究者向けセミナー Recent developments in matching markets: farsightedness and stochastic stability (applied to marriage, roommate, and maybe housing markets)
3月30日（火）	Bettina Klaus 氏 (ローザンヌ大学）	Allocation via Deferred-Acceptance under Responsive Priorities
3月30日（火）	西條辰義 氏 (大阪大学）	A Solution to Prisoner's Dilemma: 100% Cooperation in the Experiment with Approval Stage

終了したセミナー（2009年度後期）

• 日時：10月16日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Robert Veszteg 氏（Universidad Carlos III de Madrid）
• 題目：Learning and playing best response in the hide-and-seek game
• 概要：We study short and long-run behavior in hide-and-seek games in which treatments vary with symmetric and asymmetric labeling and with framing. We find that long-run behavior is not affectd by the treatment variables. In particular, we do not find that subjects fall prey to the usual focal point bias. We also study to what extent level-k reasoning, Nash equilibrium, quantal response equilibrium (QRE), fictitious play, reinforcement learning, and experience-weighted attraction (EWA) learning organize the data. All analyzed versions of these models predict the same outcome for this game. For short-run behavior, our data can not be well organized by level-k reasoning. It can be considered as the results of random play. For long-run behavior and behavior over time, the learning models outperform the static equilibrium solutions for hiders and seekers both jointly and separately. Our results suggest that experimental subjects start the game using the available actions randomly and they adjust their strategies to the opponent’s observed behavior.

• 日時：11月2日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：グレーヴァ香子 氏（慶應義塾大学）
• 題目：Voluntarily Separable Repeated Prisoner's Dilemma with Reference Letters
• 概要：We consider voluntarily separable repeated Prisoner's Dilemma in which a pair of players meet randomly and repeatedly play Prisoner's Dilemma only by mutual agreement. While the literature dealt with the case of no information flow across partnerships, we consider the case that players can issue a "reference letter" to verify at least that the partnership entered the cooperation phase. We show that such reference letters can be voluntarily provided by the partners even at some cost, and that the sheer existence of a letter shortens the trust-building periods and thus improves social efficiency.

• 日時：11月9日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス8号館5階会議室
• 報告者：Gustavo Bergantinos 氏（University of Vigo）
• 題目：The family of cost monotonic and cost additive rules in minimum costspanning tree problems
• 概要：TBA

• 日時：11月12日（木）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者：Gustavo Bergantinos 氏（University of Vigo）
• 題目：The division problem with voluntary participation
• 概要：TBA

• 日時：11月26日（木）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者： 浅古泰史氏（日本銀行金融研究所）
• 題目：Partially Binding Platforms and the Advantages of Being an Extreme Candidate
• 概要：GLOPEII web pageをご参照下さい．

• 日時：11月27日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室※3号館2階第三会議室（変更になりました）
• 報告者：加藤晋 氏（東京大学）
• 題目：Conditions for Cyclic Social Preference
• 概要：Our aims is to describe how we can capture the structure of Collective choice rule without the field expansion lemma. We consider two requirements on social preference cycle: acyclicity and　Suzumura consistency. We first examine procedural conditions for an acyclic collective choice rule. Recently, Schwartz [A Procedural Condition Necessary and Sufficient for Cyclic Social preference, J. Econ. Theory 137 (2007), 688-695] has provided a generalization of the voting paradox by using the impotent partition condition. We provide another procedural condition, and show another generalization of the voting paradox. Moreover, we connect two generalizations, and analyze the conditions for an acyclic collective choice rule. Next, we investigate the decisive structure behind Suzumura consistent collective choice rules. To capture the implication of Suzumura consistency on the decisive structure, we focus on the family of semi-decisive sets. A semi-decisive set is a group that has veto power. It is shown that if a Suzumura consistent collective choice rule satisfies weak Pareto, then the family of semi-decisive sets forms a prefilter.

• 日時：12月10日（木）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者： 海老名剛　氏（東京工業大学）
• 題目：Option Package Bundling
• 概要：Option package bundling problems arise if there is an optional good, which is valuable only if a certain (non-optional) base good is consumed together. A firm that produces both types of goods then faces the decision of whether to sell them only in a package (pure bundling), or to sell base goods both with or without optional goods, leaving the choice of consuming them together to buyers (mixed bundling). We study a model of a monopolist's option package bundling problem, in which the monopolist produces base and optional ones, with no marginal costs, and buyers' valuations are independently and uniformly distributed. We derive the optimal bundling prices, and verify that mixed bundling outperforms pure bundling if and only if the range of optional good valuation exceeds a certain size. We argue that the result is robust except in the case where the marginal cost is higher than the lowest valuation for an optional good. This suggests an interesting testable implication: the smaller the diversity of the valuation of an optional good, the more likely that the monopolist adopts pure bundling.

• 日時：12月11日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者： 藤中裕二　氏（首都大学東京）
• 題目：公平分担問題におけるメカニズムデザイン
• 概要：TBA

• 日時：12月15日（火）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者： Zaifu Yang　氏（横浜国立大学）
• 題目：Constrainedly fair job assignments under minimum wages
• 概要：A number of jobs are to be assigned to a greater number of workers. While having to abide by the law of minimum wages, firms must determine who should be assigned which job and at what salary. In such situations fair (envy-free) allocations usually fail to exist. To cope with this situation, this paper proposes a new concept of fairness, called constrained fairness. Among the set of constrainedly fair allocations, the so-called constrainedly fair and minimal allocations are of particular interest. The reason for this is that the salaries are not only compatible with the minimum wages; they are also optimal from the standpoint of cost-minimizing firms and the assignment of jobs is efficient from the viewpoint of workers. A convergent dynamic procedure that identifies constrainedly fair and minimal allocations is proposed. Furthermore, strategic properties of the mechanism are derived,and two notions of efficiency are evaluated.

• 日時：12月17日（木）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館4階401教室
• 報告者： 下津克己　氏（一橋大学）
• 題目：Sequential Estimation of Dynamic Programming Models
• 概要：This paper develops a new computationally attractive procedure for estimating dynamic discrete choice models that is applicable to a wide range of dynamic programming models. The proposed procedure can accommodate unobserved state variables that (i) are neither additively separable nor follow generalized extreme value distribution, (ii) are serially correlated, and (iii) affect the choice set. Our estimation algorithm sequentially updates the parameter estimate and the value function estimate. It builds upon the idea of the iterative estimation algorithm proposed by Aguirregabiria and Mira (2002, 2007) but conducts iteration using the value function mapping rather than the policy iteration mapping. Its implementation is straightforward in terms of computer programming; unlike the Hotz-Miller type estimators, there is no need to reformulate a fixed point mapping in the value function space as that in the space of probability distributions. It is also applicable to estimate models with unobserved heterogeneity. We analyze the convergence property of our sequential algorithm and derive the conditions for its convergence. We develop an approximated procedure which reduces computational cost substantially without deteriorating the convergence rate. We further extend our sequential procedure for estimating dynamic programming models with an equilibrium constraint, which include dynamic game models and dynamic macroeconomic models.

• 日時：12月21日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者： 小島武仁　氏（Stanford University）
• 題目：Implementing Random Assignments: A Generalization of the Birkhoff-von Neumann Theorem
• 概要：The literature on random mechanisms often describes outcomes incompletely as ``random assignments'' - expressing the probabilities that individual items are assigned to different agents - and the joint constraints that a feasible assignment must satisfy. We provide a necessary and sufficient condition (the ``bihierarchy'' condition) for the set of constraints to have the property that if the random assignment satisfies the constraints in expectation, then it is a randomization over pure assignments that each satisfy the constraints. The sets of constraints generalize those allowed by the celebrated Birkhoff-von Neumann theorem. We also provide a random algorithm to implement any such random assignment. Several applications are described, including (i) single-unit random assignment, such as school choice; (ii) multi-unit random assignment, such as course allocation and fair division; and (iii) two-sided matching problems, such as the scheduling of inter-league sports matchups. The same method also finds applications beyond economics, generalizing previous results on the minimize makespan problem in the computer science literature.

• 日時：1月30日（土）11時から12時
• 場所：早稲田大学早稲田キャンパス1号館3階310
• 報告者：篠潤之介 氏（Rutgers University）
• 題目：Farsighted Stable Sets in Hotelling's Location Games
• 概要：TBA

• 日時：2月1日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Charles Noussair 氏（Tilburg University）
• 題目：Experiment Asset Markets: Bubbles and Crashes※若手研究者向けセミナー
• 概要：TBA

• 日時：2月5日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Charles Noussair 氏（Tilburg University）
• 題目：How Others Influence One’s Behavior: Investigation with fMRI Imaging
• 概要：TBA

• 日時：2月22日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス26号館402
• 報告者：Menahem E. Yaari氏（The Hebrew University of Jerusalem）
• 題目：Justice and the Market
• 概要：TBA

• 日時：3月23日（火）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Bettina Klaus 氏(ローザンヌ大学）
• 題目：Recent developments in matching markets: matching with contracts (including couples markets, preference domains, and stability concepts)※若手研究者向けセミナー
• 概要：TBA

• 日時：3月24日（水）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Bettina Klaus 氏(ローザンヌ大学）
• 題目：Recent developments in matching markets: farsightedness and stochastic stability (applied to marriage, roommate, and maybe housing markets)※若手研究者向けセミナー
• 概要：TBA

• 日時：3月30日（火）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Bettina Klaus 氏(ローザンヌ大学）
• 題目：Allocation via Deferred-Acceptance under Responsive Priorities
• 概要：TBA

• 日時：3月30日（火）10時30分から12時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：西條辰義　氏（大阪大学）
• 題目：A Solution to Prisoner's Dilemma: 100% Cooperation in the Experiment with Approval Stage（報告は英語で行われる予定）
• 概要：Players can approve or reject the other choice of the strategy after playing a Prisoner’s Dilemma game. If both approve the other choice, the outcome is what they choose, and if either one rejects the other, it is the outcome when both defect called the Mate Selection Mechanism. The subgame perfect equilibria of this two stage game have the outcomes where both are cooperative and both are defective. However, the all pairs of weakly evolutionarily stable strategies coincide with the subgame perfect equilibria where both are cooperative and we observed 100% cooperation in the experimental session of prisoner’s dilemma game with approval stage, and 7.9% cooperation in the session of the game without the approval stage.

2009年度前期スケジュール

日程	報告者（所属）	報告タイトル
4月20日（月）	中山幹夫　氏 （慶應義塾大学）	On Coalitional Strategic Games
5月15日（金）	西村直子　氏 （信州大学経済学部）	おコメ市場とAverage Price Two-sided Auction
5月18日（月）	中原裕之　氏 （理化学研究所）	価値に基づく意思決定、その時間選好と文脈効果：神経メカニズムとその数理
6月1日（月）	Stef Tijs 氏 (Tilburg University)	Lexicographic optimization in cooperative game theory
6月8日（月）	Stef Tijs 氏 (Tilburg University)	Cooperative games and auctions
6月17日（水）	John Wooders 氏 (University of Arizona)	Auctions with Heterogeneous Entry Costs
6月22日（月）	John Wooders 氏 (University of Arizona)	Does Experience Teach? Professionals and Minimax Play in the Lab
6月23日（火）	笠島　洋一 氏 (University of Rochester)	Reflecting inequality of claims in gains and losses
7月13日（月）	坂井　豊貴　氏 （横浜国立大学）	Choosing someone with monetary transfers: a comprehensive analysis
7月21日（火）	二本杉　剛 氏 （大阪大学）	Is the Truth-Telling Equilibrium Salient?: An Experiment on Direct Nash Implementation
7月24日（金）	岩崎　敦　氏 （九州大学）	Characterizing False-name-proof Allocation Rules in Combinatorial Auctions
	大田直樹 氏 （九州大学）	Coalition Structure Generation Utilizing Compact Characteristic Function Representations
7月27日（月）	J.J. Herings 氏 （Maastricht University）	Non-cooperative Support for the Asymmetric Nash Bargaining Solution
8月31日（月）	Peter Gardenfors 氏 (Lund University)	A representation theorem for voting with logical consequences
	Jean-Francois Laslier 氏 (Ecole Polytechnique)	Approval Voting in Theory, in the Field, and in the Lab
9月2日（水）	Walter Bossert 氏 （Univerisity Montreal）	Economics of Rational Choice
9月4日（金）	Bhaskar Dutta 氏 （Univerisity of Warwick）	Honest Implementation
9月15日（火）	Michele Lombardi 氏 （University of Surrey）	Liberal Egalitarianism and the Harm Principle

終了したセミナー（2009年度前期）

• 日時：4月20日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：中山幹夫　氏（慶應義塾大学）
• 題目：On Coalitional Strategic Games
• 概要：In a strategic cooperative game, we consider four cores alpha, beta, gamma, and the one we call delta which is essentially the same to conjectural cooperative equilibria due to Currarini and Marini. We show that if every player has a dominant strategy, the beta core includes the gamma core, and therefore that the four cores refine themselves in the greek alphabetical order. Two examples will be examined to see how the refinement is realized. While no strict refinement is attained at all in the pure exchange game, a radical reduction of the alpha core is obtained in the commons game, a simple version of the Cournot game, bringing about a single strategy profile as the delta core.

• 日時：5月15日（金）16時30分から18時
• 場所：早稲田大学早稲田校舎1号館4階４０１教室
• 報告者：西村直子　氏（信州大学経済学部）
• 題目：おコメ市場とAverage Price Two-sided Auction
• 概要：TBA

• 日時：5月18日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：中原裕之　氏（理化学研究所）
• 題目：価値に基づく意思決定、その時間選好と文脈効果：神経メカニズムとその数理
• 概要：TBA

• 日時：6月1日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Stef Tijs 氏（ティルブルグ大学教授）
• 題目：Lexicographic Optimization in Cooperative Game Theory
• 概要：TBA

• 日時：6月8日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Stef Tijs 氏（ティルブルグ大学教授）
• 題目：Cooperative games and auctions
• 概要：TBA

• 日時：6月17日（水）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：John Wooders 氏（University of Arizona）
• 題目：Auction with Heterogeneous Entry Costs
• 概要：詳細につきましては報告者webpageにあります論文pdfファイルをご覧下さい．

• 日時：6月22日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：John Wooders 氏（University of Arizona）
• 題目：Does Experience Teach? Professionals and Minimax Play in the Lab
• 概要：詳細につきましては報告者webpageにあります論文pdfファイルをご覧下さい．

• 日時：6月23日（臨時）（火）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：笠島　洋一 氏（University of Rochester）
• 題目：Reflecting inequality of claims in gains and losses
• 概要：We consider the problem of dividing a resource among a group of agents who have conflicting claims on it. A typical situation is when a firm goes bankrupt and its liquidation value has to be divided among its creditors. We follow the axiomatic approach. Our main axioms are inequality preservation in gains and inequality preservation in losses [Hougaard, J. L., and Osterdal, L.P., 2005. Inequality preserving rationing. Econ Letters 87, 355-360]. These axioms require rules to reflect the inequality of claims in gains and losses. We characterize the family of rules that are continuous, order preserving in gains and losses, and inequality preserving in gains and losses: (i) for two agents, these axioms hardly restrict rules (in particular, all central rules considered in the literature satisfy them); (ii) for three agents, they are significantly more restrictive but they are satisfied by family containing a continuum of rules; and (iii) for more than three agents, they single out the proportional rule; this result confirms the central role and furthers our understanding of this rule in claims problems.

• 日時：7月13日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：坂井 豊貴 氏（横浜国立大学）
• 題目：Choosing someone with monetary transfers: a comprehensive analysis
• 概要：In situations where only one member of a group is assigned an indivisible object, money is often used as a medium to achieve fairness: When the object is an obligation to work for the group, the assigned member is paid monetary compensations for his disutility from the other members; When the object is a good or right, the assigned member pays a certain fraction of his gain to the other members. These situations are formulated as the problem of fairly allocating a single object with monetary transfers. Our purpose is to offer a comprehensive analysis to solve the problem.
  An allocation means an outcome of this problem, consisting of an assigned member and a monetary transfer vector among all members. First, we show that any fair allocation is ranked higher than any non-fair allocation for a wide class of welfare criteria including utilitarian, Nash, or leximin criteria. Second, we design a simple mechanism that simultaneously implements fair allocations in Nash equilibrium and a unique perfectly fair allocation in undominated Nash equilibrium. Third, we test the practical performance of the mechanism by a laboratory experiment. We observe that the mechanism achieves desirable allocations with high probabilities and the mode of played strategy profiles is a unique undominated Nash equilibrium, as is theoretically predicted.

• 日時：7月21日（火）（臨時）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：二本杉　剛 氏（大阪大学大学院）
• 題目：Is the Truth-Telling Equilibrium Salient?: An Experiment on Direct Nash Implementation
• 概要：本論文では，メカニズムが複数均衡を持つ際に起こりうる個人間の協調の失敗を，フォーカル・ポイント(Schelling (1960)) によって 避けることができるかどうかを実験によって検証する．本論文では 完備情報下の直接表明メカニズムによる社会的意思決定を考察して いるため，フォーカル・ポイントとなりうる均衡として，正直均衡 が考えられる．よって，同一の社会選択関数を遂行するメカニズム として，複数均衡の一つに正直均衡を持つメカニズムと持たないメ カニズムを設計し，どちらがより高い均衡達成率を実現するのかを 実験によって比較した．その結果，正直均衡を持つメカニズムの方 が有意に高い均衡達成率を示すことがわかった．』

• 日時：7月24日（金）（臨時）16時から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：(1) 岩崎　敦　氏（九州大学）(2) 大田直樹 氏（九州大学大学院）
• 題目：(1) Characterizing False-name-proof Allocation Rules in Combinatorial Auctions
  (2) Coalition Structure Generation Utilizing Compact Characteristic Function Representations
• 概要： (1) A combinatorial auction mechanism consists of an allocation rule that defines the allocation of goods for each agent, and a payment rule that defines the payment of each winner. There have been several studies on characterizing strategy-proof allocation rules. In particular, a condition called weak-monotonicity has been identified as a full characterization of strategy-proof allocation rules. More specifically, for an allocation rule, there exists an appropriate payment rule so that the mechanism becomes strategy-proof if and only if it satisfies weak-monotonicity. In this paper, we identify a condition called sub-additivity which characterizes false-name-proof allocation rules. False-name-proofness generalizes strategy-proofness, by assuming a bidder can submit multiple bids under fictitious identifiers. As far as the authors are aware, this is the first attempt to characterize false-name-proof allocation rules. We can utilize this characterization for developing a new false-name-proof mechanism, since we can concentrate on designing an allocation rule. As long as the allocation rule satisfies weak-monotonicity and sub-additivity, there always exists an appropriate payment rule. Furthermore, by utilizing the sub-additivity condition, we can easily verify whether a mechanism is false-name-proof. To our surprise, we found that two mechanisms, which were believed to be false-name-proof, do not satisfy sub-additivity; they are not false-name-proof. As demonstrated in these examples, our characterization is quite useful for mechanism verification.
  
  (2) Forming effective coalitions is a major research challenge in AI and multi-agent systems. Coalition structure generation (CSG), which involves partitioning a set of agents into coalitions so that social surplus is maximized, is a central research topic due to its computational complexity. Traditionally, the input of the CSG problem is a black-box function called a characteristic function, which takes a coalition as an input and returns the value of the coalition. However, characteristic functions that appear in practice often can be represented by a set of rules, rather than a single black-box function. It is likely that we can solve the CSG problem more efficiently by utilizing such rule-based representations and applying constraint optimization techniques to them directly. In this paper, we present new formalizations of the CSG problem by utilizing recently developed compact representation schemes for characteristic functions. We first characterize the complexity of CSG under these representation schemes. In this context, the complexity is driven more by the number of rules rather than by the number of agents. Furthermore, as an initial step towards developing efficient constraint optimization algorithms for solving the CSG problem, we develop mixed integer programming formulations and show that an off-the-shelf optimization package can solve these problems reasonably well, i.e., it can solve instances with a few hundred of agents, while the state-of-the-art algorithm (which does not make use of compact representation) can solve instances up to 27 agents.

• 日時：7月27日（月）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：J.J. Herings 氏（Maastricht University）
• 題目：Non-cooperative Support for the Asymmetric Nash Bargaining Solution
• 概要：詳細につきましては報告者webpageにあります論文pdfファイルをご覧下さい．

• 日時：8月31日（月）(1)13時から14時 (2)14時から15時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：(1) Peter Gardenfors 氏 (Lund University) (2) Jean-Francois Laslier 氏　(Ecole Polytechnique)
• 題目：(1) A representation theorem for voting with logical consequences
  (2) Approval Voting in Theory, in the Field, and in the Lab
• 概要：TBA

• 日時：9月2日（水）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館310教室
• 報告者：Walter Bossert　氏（Univerisity Montreal）
• 題目：Economics of Rational Choice
• 概要：TBA

• 日時：9月4日（金）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館310教室
• 報告者：Bhaskar Dutta 氏（Univerisity of Warwick）
• 題目：Honest Implementation (joint paper with Arunava Sen)
• 概要：TBA

• 日時：9月15日（火）16時30分から18時
• 場所：早稲田大学早稲田キャンパス1号館2階現代政治経済研究所会議室
• 報告者：Michele Lombardi 氏（University of Surrey）
• 題目：Liberal Egalitarianism and the Harm Principle
• 概要：TBA

関連情報

以下は本研究会に関連する連続講義・セミナーのお知らせです．

Games and Auctions: Theory and Experiments

• 講師・報告者：John Wooders (University of Arizona) 　　　
• 概要：John Wooders教授は実験経済学、ゲーム理論、オークション理論、数理経済学の著名な研究者であり、一流国際雑誌に多くの論文を掲載している。今回の一連 のセミナーではオークションをメインテーマとして、理論（主としてゲーム理論）と実験に関して大学院生向け集中講義を行う。
• 連続講義スケジュール（以下はすべて早稲田大学早稲田キャンパスにて行われます．）

No.	日時	トピック	会場	備考
Lecture 1	29 May Fri. 14:45-16:15	Mixed-strategy experiments: The O’Neill game and “Blind Stealing”	4-202
Lecture 2	1 June Mon 13:00-14:30	Perfect Bayesian Equilibrium of Blind Stealing. Discussion of experimental results.	4-202	Readings:O Neill, B. (1987): “Nonmetric Test of the Minimax Theory of Two-Person Zero-Sum Games,” Proceedings of the National Academy of Sciences 84, 2106-2109. Walker, M., and J. Wooders (2001): “Minimax Play at Wimbledon,” American Economic Review 91, 1521-1538.
Lecture 3	5 June Fri. 14:45-16:15	Auction experiments: First and second price sealed bid auctions, common value auctions	4-202
Lecture 4	8 June Mon 13:00-14:30	First Price Auctions	4-202	Readings: Krishna Chapters 1 and 2*
Lecture 5	12 June Fri. 14:45-16:15	The Revenue Equivalence Principle	4-202	Readings: Krishna Chapter 3*
Lecture 6	15 June Mon 13:00-14:30	Extensions-risk aversion, budget constraints	4-202	Readings: Krishna Chapter 4*
Lecture 7	19 June Fri. 14:45-16:15	Mechanism Design	4-202	Readings: Krishna Chapter 5*
Lecture 8	22 June Mon 13:00-14:30	Buy It Now Auctions	4-202	Readings: Reynolds, S., & J. Wooders (2009): “Auctions with a Buy Price,”EconomicTheory 38, 9-39. Shahriar, Q., and J. Wooders (2007): “An Experimental Study of Auctions with a Buy Price Under Private and Common Values,”University of Arizona Working Paper #07-19.
Lecture 9	26 June Fri. 14:45-16:15	Auctions with interdependent values	4-202	Readings: Krishna Chapter 6*

• * Krishna,V. “Auction Theory” Academic Press, 2002

Game Theory Lecture Series

• 講師：Rodica Branzei (Alexandru Ioan Cuza University) 　　　
• 概要：Rodica Branzei准教授はStef Tijs教授ら多くのゲーム理論研究者との共著論文がある。今回の連続講義ではRodica Branzei准教授の最近の著書および最新の研究成果に関して、大学院生向けに講義を行う。
• スケジュール（以下はすべて早稲田大学早稲田キャンパスにて行われます．）

No.	日時	トピック	会場	備考
Lecture 1	2 June Tue. 16:30-18:00	Multi-choice Games I	4-206
Lecture 2	3 June Wed. 16:30-18:00	Multi-choice Games II	4-202
Lecture 3	5 June Fri. 9:00-10:30	Multi-choice Games III	4-202
Lecture 4	9 June Tue 16:30-18:00	Interval Games I	4-206
Lecture 5	10 June Wed. 16:30-18:00	Interval Games II	4-202

以下は本研究会に関連するWorkshopの情報です．

• The Sixth Asian General Equilibrium Theory Workshop(GETA2009)
• Waseda Game Theory Workshop
• FRMES2009
• LGS6