Microeconomics Workshop 2002

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※ 1月29日現在　近い予定から順に掲載しています。

※ 以下本年度終了分

日時：

4月16日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

In-Uck Park(ISER, Osaka University/University of Pittsburgh)

Repeated Moral Hazard with Renegotiation and Free Access to Credit Markets

Abstract:

This paper studies the impact of renegotiation on dynamic contractual rela-tionships, when the agent's "interim preference" over continuation contracts is private information because personal financial decisions affect it via a wealth effect. The main result is a severe loss of incentive provision: renegotiation-proof contracts invariably cause the agent to shirk (i.e., exert minimal effort) in every non-initial period. The paper proves this result for the case that the agent exhibits strictly monotone absolute risk aversion. It also discusses the basic differences from the results of Fudenberg and Tirole (1990) on the same issue in a one-shot model.

日時：

4月23日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

尾山大輔 Daisuke Oyama (東大大学院)

Rationalizable Foresight Dynamics: Evolution and Rationalizability

Abstract：

This paper considers a dynamic situation where rationality is common knowledge among infinitesimal agents, but beliefs may not be coordinated with each other. A rationalizable foresight path is a feasible path of behavior pattern along which every agent takes an action that maximizes his expected discounted payoff against another path which is in turn a rationalizable foresight path. An action distribution is accessible from another distribution under rationalizable foresight if there exists a rationalizable foresight path from the latter to the former. An action distribution is said to be a stable state under rationalizable foresight if no rationalizable foresight path departs from the distribution. A set of action distributions is said to be a stable set under rationalizable foresight if it is closed under accessibility and any two elements of the set are mutually accessible. Stable sets under rationalizable foresight always exist. These concepts are compared with the corresponding concepts under perfect foresight. Every stable state under rationalizable foresight is shown to be stable under perfect foresight. But the converse is not true. An example is provided to illustrate that the stability concepts under rationalizable foresight gives a sharper prediction than that under perfect foresight.

日時：

4月30日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

佐藤主光　Motohiro Sato （一橋大学大学院経済学研究科）

Political Economy of Fiscal Decentralization Resume

Abstract：

Politics has been noted to serve as major constraints in reform of any sorts. In the context of fiscal decentralization, the present paper aims to establish a conceptual framework for better understanding of relationship between fiscal reform and political constraints, the latter of which involves several stakeholders - local governments, regional representatives and residents. It would be argued that political constraints are not extrinsic but emerge as equilibrium consequence of the former, addressing government turnover that decentralization induces. Accounting for inter-dependency between them, we derive and characterize political constraints on decentralization. Then we claim that "big bang" approach, or a large-scale decentralization can make political break-through, enhancing welfare more than a moderate decentralization.

日時：

5月7日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

John Sutton (LSE)

Rich Trades, Scare Capabilities: Industrial Development Rivisited

日時：

5月14日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

大森裕浩 Yasuhiro Omori (東京大学大学院経済学研究科)

マルコフ連鎖モンテカルロ法の最近の展開　

参考文献：

大森裕浩(2001)「マルコフ連鎖モンテカルロ法の最近の展開」 日本統計学会誌, 第31巻, 第3号, 305-344.

日時：

5月21日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

浅野貴央 Takao Asano (東北大学大学院)

Portfolio Inertia under Ambiguity　

Abstract：

We consider an individual's portfolio selection problems. By introducing the concept of ambiguity, we show the existence of portfolio inertia under the assumptions that a decision maker's beliefs are captured by an inner measure, and that her preferences are represented by the Choquet integral with respect to the inner measure. Under the concept of ambiguity, it is considered that a sigma-algebra is not necessarily an appropriate set of events to which a decision maker assigns probabilities. Furthermore, we study the difference between ambiguity and uncertainty by considering investors' behavior.

日時：

5月28日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

高橋悟 Satoru Takahashi (東京大学大学院)

K-Coordination Games with Perfect Information　

Abstract：

We consider coordination games with perfect information. A common interest game is a game that has a unique Pareto-dominant outcome. A game is said to be a K-coordination game if there exists a positive number e_i for each player i such that player i can decrease player j's payoff by at most Ke_j/e_i multiplied by player i's cost. The number K represents the degree of common interest. A game is said to taper off if the game is a K-coordination game and the greatest variation of some player's payoff shrinks to zero rapidly compared to K. We show that if a game with perfect information tapers off, then every subgame perfect equilibrium outcome is efficient in this game.

日時：

6月4日（火）3:00-6:30pm

場所：

東京大学経済学研究科棟第2共同研究室（経済学部新棟12階）

at the Conference Room B (No.2) on the 12rd floor of New Econ. Building

報告：

Bill Sandholm(University of Wisconsin, Madison)

Cultural Evolution and Its Discontents (with Timur Kuran, USC)

Abstract：

A community's culture is defined by the preferences and equilibrium behaviors of its members. Contacts among communities alter their cultures through two mechanisms: behavioral adaptations motivated by coordination and preference changes shaped by socialization and the need for self-consistency. The paper analyzes a model of cultural integration in which preferences and behaviors vary continuously, and it describes a broad set of conditions under which the end result is cultural homogenization. Limiting outcomes are independent of the conformity pressures within the constituent cultures. The analysis suggests that efforts to keep existing cultures unchanged are in direct conflict with policies that facilitate social integration.

Josef Hofbauer (Universitat Wien)　

Convergence of Stochastic Fictitious Play

Abstract：

For certain classes of games (zero sum games, potential games, supermodular games) stochastic fictitious play converges to equilibrium.

日時：

6月11日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

松島　斉　Hitoshi Matsushima (東京大学 University of Tokyo)

Repeated Games with Correlated Private Monitoring and Secret Price Cuts

Abstract：

This paper investigates two-player infinitely repeated games where the discount factor is less than but close to unity. We assume that monitoring is imperfect and private, and players’ private signals are correlated through the unobservable macro shock. We show that a sequential equilibrium payoff vector approximates efficiency in a wide class of environments when the size of the set of private signals for each player is sufficiently large in comparison with the size of the set of possible macro shocks. We require almost no condition on the accuracy of players' monitoring technology. We argue that the use of review strategy works very well in the private monitoring case, although it does not work well in the public monitoring case. We apply our efficiency result to a model of price-setting duopoly a la Stigler (1964), where each firm’s price choice is unobservable to its rival firm and the sales level for each firm is regarded as its own private signal. Contrarily to Stigler' s conjecture, the full cartel collusion can be self-enforcing even if firms cannot communicate and have the option of making secret price cuts.

日時：

6月18日（火） 5:30-7:00pm ※開始時間にご注意下さい

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

In-Koo Cho (University of Illinois, Urbana-Champaign)

Learning Aspiration in Repeated Games (with Akihiko Matsui, University of Tokyo)

Abstract：

We characterize the behavior of boundedly rational agents who play an infinitely repeated symmetric 2x 2 game according to a simple rule of thumb: he continues to play the same action if and only if the action generates one period payoff that exceeds the aspiration level, that summarizes a history according to the average of the past payoff. This simple rule of thumb induces a ensible outcome. In the coordination game, for example, the two players achieve cooperation with probability 1 in the long run, and in the battle of sexes, the outcome converges to either one of the two Pareto efficient outcomes. In the prisoner's dilemma game, the players cooperate in the limit if and only if the gains from defecting against cooperation is not too large in the prisoner's dilemma game. This result sharply contrasts to Karandikar et al (JET '98), claiming that under a similar learning process, the cooperation occurs for all possible configuration of payoff vectors in the prisoner's dilemma.

日時：

6月25日（火） 4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

Jay Wilson (Michigan State University)

Tiebout Competition vs. Political Competition: The Case of a University Campus PAPER 1 PAPER 2

※ 7月2日（火）は休講です。 No lecture on July 2.

日時：

7月9日（火） 4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

神谷和也 (東京大学)・清水崇（一橋大学）

Real Indeterminacy of Stationary Equilibria in Matching Models with Media of Exchange

Abstract:

The purpose of this paper is twofold. First, we show that, in any matching model with perfectly divisible media of exchange, stationary equilibria are generically indeterminate. That is if there exists a stationary equilibrium, then, in its neighborhood, we can generically find a continum of them in which real allocations are not constant. Second, we present a new technique to prove the existence of stationary equilibria; especially, it is applicable to the case that both money and goods are perfectly divisible.

日時：

7月16日（火） 4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

高橋文郎 (中央大学 Chuo University / CIRJE)

日本のベンチャーキャピタルの現状と課題

Abstract:

アメリカのベンチャーキャピタルは、アーリーステージ（成長初期段階）企業に対するハイリスク・ハイリターン型の投資と経営へのコミットメントを行う少数精鋭のパートナーシップ組織として発達した。これに対し、日本のベンチャーキャピタルは、多くが金融機関の系列会社で、投資対象はレーターステージ（成長後期）企業が多く、経営へのコミットメントは少なかった。 　通商産業省（当時）が中心になって行ったベンチャーキャピタルの投資パフォーマンス調査によると、近年、わが国のベンチャーキャピタル・ファンドの投資リターン（IRR）はゼロないしマイナスとなっている。この低パフォーマンスは、わが国のベンチャーキャピタルの特徴に根ざした構造的問題と考えられる。今後、わが国のベンチャーキャピタルが投資パフォーマンスを高めるためには、親会社からの経営・人材面の独立や専門的な人材の育成など、投資先企業の「企業価値を高める」ための経営支援を行うための体質改善が必要とされよう。

日時：

7月22日（月 Monday） 4:50-6:30pm ※曜日と場所が通常と異なりますのでご注意下さい。

場所：

東京大学経済学研究科棟第1共同研究室（経済学部新棟12階）

at the Conference Room A (No.1) on the 12th floor of New Econ. Building

報告：

Ronald W. Jones (University of Rochester)

Trade and Wages: A deeper Investigation

日時：

7月23日（火） 4:50-6:30pm

場所：

東京大学経済学研究科棟第3教室（経済学部新棟3階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

Yiting Li (National Tsing Hua University, Taiwan / CIRJE)

Private Money, Bank Operations and Government Regulations

Abstract:

This paper studies how the functions and competition of inside and outside money are affected by financial operations and regulations in an economy with explicit trade frictions. We find that claims on banks circulate when the redemption rate is low, adn dominate fiat money in the rate of return. When the quantity of fiat money is limited, coexistence of private money and fiat money dominates in welfare term the equilibria where either one is used as the unique medium of exchange. If the quantity of fiat money is ample, banks may accept it as deposits and keep some vault cash for redeeming financial claims. Under this operation, changes in the quantity of fiat money do not affect real activity and prices. A binding reserve requirement policy eliminates neutrality of money, under which a tightening monetary policy creates a credit-rationing phenomenon. Although restrictions on note issue may harm bank's intermediation function, it may be beneficial to the public.

日時：

10月4日（金）4:00-6:00pm

※ 第1回目（10月1日）は台風のため休講になりましたので振替のワークショップを開催します。時間と場所が通常と異なりますのでご注意下さい。

場所：

東京大学経済学研究科棟第1共同研究室（経済学部新棟12階）

at the Conference Room A (No.1) on the 12th floor of New Econ. Building

報告1：

4:00pm-4:40pm

岩田正隆 (東京大学大学院, GS of Econ., University of Tokyo)

Comparison of Commodity Money and Fiat Money

Abstract:

This paper analyzes the effect of stochasticity in production over some monetary exchange economies, in terms of welfare. Especially we focus on comparison of a commodity money economy and a fiat money economy. Agents in dynamic exchange economy are faced with vulnerability of production and sometimes supplies of goods fail. With a certain market structure which has market places specified in each pair of types of goods, fiat money economy may become relatively better when the vulnerability of production is sufficiently harsh.

報告2：

4:40pm-5:20pm

竹内大介 Daisuke Takeuchi (東京大学大学院, GS of Econ., University of Tokyo)

Dynamic Product Innovation in a Vertically Differentiated Duopoly

Abstract:

I present a dynamic approach to oligopoly models with vertical product differentiation. I examine how the difference between the qualities of firms affects the incentive to invest for product innovation. In the model I show that, when the investment cost satisfies some conditions, there exists a Markov perfect equilibrium strategy such that a rm producing superior goods invests when the quality difference is not large and a firm does not invest otherwise. Moreover I can show that product differentiation always exists in steady state and the firms have larger incentive to invest when the difference is smaller.

報告3：

5:20pm-6:00pm

小井田伸雄 Nobuo Koida (東京大学大学院, GS of Econ., University of Tokyo)

Moderation Premiums in the Choquet Expected Utility with Transformed Probabilities

Abstract:

In this paper, we propose a notion of moderation premiums, a new concept of premiums for uncertainty, where the probability of events is more ambiguous than additive probability measures. We consider the Choquet expected utility (Schmeidler (1989)) with transformed probabilities (CEUTP), or mathematical equivalently, expected utility with rank-dependent probabilities (EURDP, Quiggin (1982) and Yaari (1987)). In these situations, we focus on the probability shift effects induced by shifts of probability from extreme outcomes to a moderate outcome, which does not occur in the standard expected utility, while the standard risk aversion analysis focuses on the magnitude effects induced by increases in magnitudes of possible outcomes. We define two types of moderation premiums for the former effects and show that they can be approximated by the Arrow-Pratt measure (Arrow (1965), Pratt (1964)) applied to transformation function (or A-Pt measure). We also investigate the relations between these local properties and global ones, which parallels the standard risk aversion analysis. Further, we consider a simple "portfolio choice" problem and show the difference　from the standard analysis.

日時：

10月8日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告1：

4:50pm-5:20pm

高野久紀 Hisaki Kono(東京大学大学院, GS of Econ., University of Tokyo)

Heterogeneous Contests and Less Informative Signals joint with Nobuyuki Yagi (GS of Econ., University of Tokyo)

Abstract:

We consider the optimal contest structure in which neither types of agents nor their exerted effort levels are observable to the principal who administers the prize(s) and control the accuracy of noisy signal. We argue that, when agents are heterogeneous, the optimal incentive schemes for eliciting high efforts from the contestants are to base the prize(s) on an output signal that is made deliberately noisy. This is because the prospect of luck, which is guaranteed with a positive probability if the output signal is sufficiently noisy, induces the low-ability type agent not to give up but to work hard so as to increase the probability of such luck. This, in turn, makes the competing high-ability agent to work hard as well. This is a mechanism which serves to provide work incentives for both high- and low-ability agents.

報告2：

5:20pm-5:50pm

山森哲雄(東京大学大学院, GS of Econ., University of Tokyo)

An Indirect Evolutionary Approach to Equilibrium Selection

Abstract:

This paper studies equilibrium selection in symmetric 2x2 coordination games based on a stochastic evolutionary model in which preferences and behavior of agents co-evolve. We treat the preferences of agents as endogenous in the way the evolution of preferences is driven by the differences in their reproductive success. This way is based on the indirect evolutionary approach. We identify the preferences that essentially determine the consequence of equilibrium selection.

報告3：

5:50pm-6:20pm

木原 匡(東京大学大学院, GS of Econ., University of Tokyo)

The Role of Queuing Cost in Bertrand Competition

Abstract:

One of the most famous prophecies in oligopoly is so-called Bertrand paradox: that is to say the unique outcome of price competition in a duopolistic market with constant marginal costs and homogeneous products has the two firms price at marginal cost. The logic that underlies this striking result is so simple: the lower-priced firm would take the whole demand, so that the firms reduce prices until they are equal to marginal cost. Even a duopoly would suffice to restore perfect competition.

The situation is quite different in the presence of congestion. We adopt waiting in queues to model congestion. Consumers stand in queues waiting for their turns when the demand exceeds firms’ capacities. Computer servers have been a main subject in queuing theory. However these features, providing goods with service time and rationing by waiting queues, appear in the markets for a wide variety of products.

Our main results are as follows; Pricing equal to marginal cost is not a Nash equilibrium since the firm can take customers if its price is a little higher than the rival. Assuming consumers’ homogenity in reservation value, the unique equilibrium is such that both firms charge the reservation value if the size of market is sufficiently large. Otherwise we don’t have any pure strategy equilibrium.

※ 10月15日（火）は休講 No Lecture

日時：

10月22日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

宮原泰之(神戸大学)

Repeated Games with Observation Costs joint with Eiichi Miyagawa (Columbia University) and Tadashi Sekiguchi (Kobe University)

日時：

10月29日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

青柳真樹(大阪大学)

Efficient Collusion in Repeated Auctions with Communication

Abstract:

This paper studies collusion in repeated auctions when bidders communicate prior to each stage auction. The paper presents a folk theorem for independent and correlated private signals and general interdependent values. Specifically, it identifies conditions under which an equilibrium collusion scheme is fully efficient in the sense that the bidders' payoff is close to what they get when the object is allocated to the highest valuation bidder at the reserve price in every period.

日時：

11月5日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

小幡績(一橋大学)

Pyramid Groups, Financial Distress and Investor Protection

Abstract:

Business groups are a prevalent form of corporate organization in developing countries around the world. A family often controls all firms in such groups via a pyramid structure. I present a model in which the ultimate owner of a group of firms may prop up a firm experiencing financial distress. I show that the propping up function of a group is enhanced under a pyramid ownership structure. However, the effect of the pyramid structure is weaker in countries with effective investor protection. In the absence of good investor protection, pyramids can prop up financially distressed firms at expense of minority shareholders. My predictions are supported by the data on East Asian firms from 1995 to 1999. While financially distressed firms with group affiliation have higher valuation than non-affiliated firms when cash flow rights are aligned with control rights, they have the lower valuation than non-affiliated firms when there is a separation of ownership from control.

日時：

11月12日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

谷本雅之(東京大学)

戦前期日本の産業発展と生産組織―「問屋制」と「小経営」―

日時：

11月19日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

尾崎裕之(東北大学)

Economics of Self-Feeding Fear joint with Kiyohiko G. Nishimura (University of Tokyo)

Abract：

A model of self-feeding fear is presented. Suppose that an economic agent is (1-ε)×100% certain that uncertainty she faces is characterized by a particular probability measure, but that she has a fear that, with ε× 100% chance, her conviction is completely wrong and she is left perfectly ignorant about the true measure in the present as well as in the future. We call this situation ε-contamination of confidence. In this situation, if the economic agent follows Bayesian procedure or its variant, which is considered as rational in the theory of economics, her confidence erodes after having new observation.

日時：

11月26日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

三輪芳朗(東京大学)

Who Appoints Them, What Do They Do? Evidence on Outside Directors from Japan joint with J. Mark Ramseyer (Harvard University) (CIRJE Discussion Paper 2002-CF-159)

日時：

12月3日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

小林　創 Hajime Kobayashi(大阪府立大学)

Emergence of Leadership in Teams joint with Hideo Suehiro (Kobe University)

日時：

12月10日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

Johannes Moenius(Northwestern University/CIRJE)

Trade, Law and Product Complexity, joint with Daniel Berkowitz, Katharina Pistor

Abstract:

How does the quality of national institutions that enforce the rule of law influence international trade? Anderson and Marcouiller (2001) argue that bad institutions located in the importer's country deter international trade because they enable economic predators to steal and extort at the importer's border. We complement this research and show how good institutions located in the exporter's country enhance international trade and, in particular, trade in complex products whose characteristics are difficult to fully specify in a contract. We build a model in which exporter and importer institutions impact international transaction costs as well as domestic production costs in complex and simple product markets. We find strong evidence for the model's predictions: most notably, the overall impact of exporter institutions is strongest in complex product markets, the overall impact of importer institutions is strongest in simple product markets and the impact of institutions on transaction costs is most important in complex product markets.

日時：

12月17日（火）4:50-6:30pm

場所：

東京大学経済学研究科棟第３教室（経済学部新棟３階）

at the Lecture Hall C (No.3) on the 3rd floor of New Econ. Building

報告：

佐々木弾Dan Sasaki (東京大学)

Credit Discrimination

"Stop Blaming the Victim: Credit Discrimination without Moral Hazard"

Abstract:

Can a specific class of borrowers be treated discriminatorily even if (1) the class is identical with the remainder of the population in terms of their ability and their use of borrowed money, and also (2) lenders are rational and competitive? Unlike most of the existing statistical discrimination literature, the endogenous discrimination in this paper does not involve hidden actions which are distinct between the discriminated-against and the discriminated-for. Thereby it is successfully shown that a discriminatory self-fulfilling prophecy can be endoge-nously sustained even when the class of borrowers do nothing "blameworthy" to contribute to such a prophecy.

日時：

1月14日（火）4:20-7:00pm ※修士論文報告会※

場所：

東京大学経済学研究科棟第8教室（経済学部旧棟地階）

at the Lecture Hall Ｈ (=No.8) on the basement floor of Old Econ. Building

4:20 嶋　宏之（藤原･松井･佐々木）因果関係の理解と制度形成の関連

5:00 佐藤　愛 Megumu Sato（伊藤元･藤原･八田）How can governments act in conformity to international regulations and also protect the truly damaged domestic firms

5:40 山田昌弘（藤原･玄田･伊藤元）若年有業者の転職行動

6:20 小坂賢太 Kenta Kosaka（伊藤元・玄田･岩田）Trade liberalization and labor market distortion in developing countries **REVISED**

日時：

1月15日（水）3:40-7:00pm ※修士論文報告会※

場所：

東京大学経済学研究科棟第4教室（経済学部新棟）

at the Lecture Hall D (=No.4) on the 3rd floor of New Econ. Building

3:40 島　俊彦（松井･佐々木･神取）Search for Auctions

4:20 関口洋平 Yohei Sekiguchi（松井･佐々木･松島）Ex Ante Price Offers and Walrasian Outcome

5:00 笠島洋一（田淵･金本･松井）ｵﾌｨｽと住宅の住み分けに関する考察

5:40 吉野　薫（田淵･松島･金本）２要素のtax-competitionﾓﾃﾞﾙを用いた比較動学分析

6:20 菅野　新（柳川･伊藤元･柳田）国際貿易におけるuniform tariff規制の効果とその理論分析

日時：

1月21日（火）4:20-7:00pm ※修士論文報告会※

場所：

東京大学経済学研究科棟第8教室（経済学部旧棟地階）

at the Lecture Hall Ｈ (=No.8) on the basement floor of Old Econ. Building

4:20 尾川 僚（神取･松島･松井）Repeated Moral Hazard with History Dependence

5:00 流田辰也（神取･松島･松井）Announced Reserve Prices and Secret Reserve Prices

5:40 神谷安都子（柳川･三輪･松島）特許法改定の実証分析−日本の医薬品産業を中心として−

6:20 扇内健太郎（柳川･松島･三輪）企業のﾊﾟﾌｫｰﾏﾝｽと株式保有構造の因果関係に対する考察−日本の製造業を中心とした実証分析−

日時：

1月23日（木）11:45-13:15 ※臨時セミナー※

場所：

東京大学経済学研究科棟第４教室（経済学部新棟３階）

at the Lecture Hall D(=No.4) on the 3rd floor of New Econ. Building

報告：

Randal Watson(Northwestern University)

Product Variety and Competition in the Retail Market for Eyeglasses

Abstract:

I analyze an original dataset on the display inventories of several hundred eyewear retailers to study how firms' product-range choices depend on separation from rivals in geographically-differentiated markets. A two-stage estimation approach is used, employing Seim's (2002) structural entry model for firms' first-stage location choices, followed by reduced-form store-level variety regressions. Following Mazzeo (2000) estimates from the first stage are used in the second stage to correct for the endogeneity of rivals' locations.

Results from the first-stage entry model suggest that sellers' post-entry profits decline in the number of nearby competitors, although the first such rivals exert a significantly less negative effect. The second-stage results show that sellers' product ranges also are non-linear functions of the number of nearby rivals. When a seller is relatively isolated in the product space its equilibrium product variety is increasing in nearby competition. But for more than a few nearby rivals variety starts to decline with extra competitors, consistent with the eventual dominance of business-stealing among proximate sellers.

日時：

1月28日（火）4:20-7:00pm ※修士論文報告会※

場所：

東京大学経済学研究科棟第8教室（経済学部旧棟地階）

at the Lecture Hall Ｈ (=No.8) on the basement floor of Old Econ. Building

4:20 岡野芳隆（神取･松井･松島）Evolution and Local Interaction with One Forward Looking Player

5:00 宮崎浩一（松島･柳川･松井）Separation of Powers under incomplete information

5:40 橋本成央（三輪･柳川･松島）製造物責任法施行による影響の実証分析

6:20 中尾隆宏（柳川、三輪、松島）規制が回避可能な場合の最適なエンフォースメント

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