The Stability of Hedonic Coalition Structures

We consider the partitioning of a society into coalitions in purely hedonic settings, i.e., where each player's payoff is completely determined by the identity of other members of her coalition. We first discuss how hedonic and nonhedonic settings differ and some sufficient conditions for the existence of core stable coalition partitions in hedonic settings. We then focus on a weaker stability condition: individual stability, where no player can benefit from moving to another coalition while not hurting the members of that new coalition. We show that if coalitions can be ordered according to some characteristic over which players have single-peaked preferences, or where players have symmetric and additively separable preferences, then there exists an individually stable coalition partition. Examples show that without these conditions, individually stable coalition partitions may not exist. We also discuss some other stability concepts, and the incompatibility of stability with other normative properties. Journal of Economic Literature Classification Numbers: C71, A14, D20.     

Legislative Bargaining and Coalition Formation

The finite horizon version of D. P. Baron and J. Ferejohn's [1989, Amer. Polit. Sci. Rev.83, 1181-1206] legislative bargaining model is investigated. With three or more periods, a continuum of divisions is supportable as subgame perfect equilib- ria. There exist equilibria where coalitions larger than a minimal winning coalition receive strictly positive shares. With sufficiently patient players and a sufficiently long horizon, any interior distribution is supportable as an equilibrium. In contrast, a generic uniqueness result applies when introducing heterogenous time preferences. The unique backwards induction equilibrium in the perturbed game is nonstationary, and neither the original (symmetric) nor the perturbed game provides guidance for equilibrium selection in the infinite game. Journal of Economic Literature Classification Numbers: C73, C78, D72, D78, H49.     

Minimum-Effort Coordination Games: Stochastic Potential and Logit Equilibrium

This paper revisits the minimum-effort coordination game with a continuum of Pareto-ranked Nash equilibria. Noise is introduced via a logit probabilistic choice function. The resulting logit equilibrium distribution of decisions is unique and maximizes a stochastic potential function. In the limit as the noise vanishes, the distribution converges to an outcome that is analogous to the risk-dominant outcome for 2 × 2 games. In accordance with experimental evidence, logit equilibrium efforts decrease with increases in effort costs and the number of players, even though these parameters do not affect the Nash equilibria. Journal of Economic Literature Classification Numbers: C72, C92.     

国有资产并购价格的形成机制与合谋风险防范

文章研究了公司并购价格尤其是国有企业并购价格的形成机制.首先讨论了在非合作博弈前提下,强制一次成交与多回合讨价还价的解空间;然后引入交易主持人的效用函数,分析合谋操纵下的价格扭曲及对资产出卖方的利益侵害;最后从多方面提出风险防范的改进措施.相关结论应用于国有企业的并购重组具有很强的现实意义,不但能提高交易的撮合成功率,有利于盘活国有不良资产,而且能有效防范串谋带来的不利影响,防止国有资产的非正常流失.     

Coalition Emergency Response System, City Security and City Sustainable Development

The relations among the establishment of Coalition Emergency Response System （CERS）, city security and city sustainable development are analyzed in the article. According to the relation analysis, it is concluded that cities should build up their CERS to deal with the thread of damage in China. The recommendations about the establishment of the system are also provided.     

Stability and Segregation in Group Formation

This paper presents a model of group formation based on the assumption that individuals prefer to associate with people similar to them. It is shown that, in general, if the number of groups that can be formed is bounded, then a stable partition of the society into groups may not exist. (A partition is defined as stable if none of the individuals would prefer be in a different group than the one he is in.) However, if individuals' characteristics are one-dimensional, then a stable partition always exists. We give sufficient conditions for stable partitions to be segregating (in the sense that, for example, low-characteristic individuals are in one group and high-characteristic ones are in another) and Pareto efficient. In addition, we propose a dynamic model of individual myopic behavior describing the evolution of group formation to an eventual stable, segregating, and Pareto efficient partition. Journal of Economic Literature Classification Numbers: C72, H41.     

Games of Climate Change with International Trade

We analyse games of greenhouse gas emission reduction in which the emissions and the emission reduction costs of one country depend on other countries' emission abatement. In an analytically tractable model, we show that international trade effects on costs and emissions can either increase or decrease incentives to reduce emissions and to cooperate on emission abatement; in some specifications, optimal emission reduction is unaffected by trade. We therefore specify the model further, calibrating it to larger models that estimate the costs of emission reduction, trade effects, and impacts of climate change. If trade effects are driven by total emission reduction costs of other countries cooperation is slightly more difficult than in the case without trade effects. If trade effects are determined by relative emission reduction efforts in other countries, cooperation becomes easier. Carbon leakage does not affect our qualitative insights, although it does change the numbers.     

Two‐Aggregate Games: Demonstration Using a Production–Appropriation Model

We expand the scope of the two‐aggregate method by applying it to a situation in which many heterogeneous players are free to contribute to both aggregates. Such situations naturally arise in various resource allocation problems. Hence, our method is useful in many applications. A production–appropriation model is employed to illustrate how the problem of establishing the Nash equilibrium can be reduced from solving n>2 best‐response functions in n unknowns to solving two consistency conditions in two unknowns. We then conduct a comparative static exercise that the conventional approach could not handle easily, if at all, to demonstrate the power of our method.     

高技术企业技术标准合作网络与质量互动模型

指出高技术企业趋向于通过合作网络来参与技术标准竞争,对技术标准合作网络进行描述,并研究其互补产品质量变化引起的互动,建立质量互动模型,得出标准合作网络内各主体之间的决策和行动是相互影响的结论。     

Socially Subjective Equilibrium in Strategic Form Games

This study provides a new framework and a new equilibrium concept, which are able to describe the situation where people have various images of the society and have various solution concepts for social outcomes, and where people accept the social outcomes. In socially subjective equilibrium, people have a coherence of their own norms in two senses. One is the consistency of the norm itself. Imagined outcomes should satisfy a certain (subjective) solution concept. The other is the consistency between the imagined outcomes and realized one. These are the main features of our equilibrium concept. This paper forms a part of my doctoral thesis, which is titled “On socially subjective equilibrium”. The first person I would like to thank is my direct supervisor Professor Ken Urai (Osaka University). I obtained a basic idea of the main concept of my doctoral thesis, that is, the solution concept scheme, from Professor Urai. I am grateful to Professor Hiroaki Nagatani (Osaka University) and Professor Ken-Ichi Shimomura (Kobe University), who monitored my works and took efforts in providing me with valuable comments on earlier versions of my thesis. I also obtained a fruitful advice from Professor Kenichi Amaya (Kobe University). Lastly, I specially thank to Kozo Shiraishi (Osaka University).     

Perfect Information and Potential Games

Games with perfect information giving rise to potential normal forms are described. For agent normal forms, a potential is defined such that a strategy profile is a maximizer for the potential if and only if it is a subgame perfect equilibrium. In the normal form of any game with perfect information, every better reply path where the players do not change their choices at irrelevant nodes leads to an equilibrium. Journal of Economic Literature Classification Number: C72.     

Coalition and Party Formation in a Legislative Voting Game

We examine a legislative voting game where decisions are to be made over both ideological and distributive dimensions. In equilibrium legislators prefer to make proposals for the two dimensions together, despite having preferences that are separable over the two dimensions. The equilibria exhibit interaction between the ideological and distributive dimensions, and the set of legislators who approve winning proposals does not always consist of ideologically adjacent legislators. There is more than one ideological decision that has a positive probability of being proposed and approved. We show that legislators can gain from forming political parties, and consider examples where predictions can be made about the composition of parties. Journal of Economic Literature Classification Numbers: D72, C71, C78.     

Average Monotonic Cooperative Games

A subclass of monotonic transferable utility (T.U.) games is studied: average monotonic games. These games are totally balanced. We prove that the core coincides with both the bargaining set à la Davis and Maschler and the bargaining set à la Mas-Colell. To obtain this result a technique based on reduced games is used. Journal of Economic Literature Classification Number: C71     

Combinatorial Games under Auction Play

ARichman gameis a combinatorial game in which, rather than alternating moves, the two players bid for the privilege of making the next move. The theory of such games is a hybrid between the classical theory of games (von Neumann, Morgenstern, …) and the combinatorial theory of games (Berlekamp, Conway, Guy, …). We expand upon our previous work by considering games with infinitely many positions as well as several variants including thePoorman variantin which the high bidder pays a third party (rather than the other player).Journal of Economic LiteratureClassification Number: C7.     

创业网络中信息交互行为的协作博弈分析

设计了基于预期和规范规则的合作竞争博弈模型,并利用仿真方法进一步分析创业网络中的信息博弈协作行为。仿真结果显示:在创业网络中,采取合作策略的创业者的成功率一直大于采取不合作策略的创业者。指出在创业网络中有效利用和管理创业者的信用度会使创业网络中的信息交互行为更为规范和有效。     

窜货的成因及其对策研究:基于博弈论的视角

在我国企业的分销渠道建设中往往会遇到窜货现象。它是现代市场营销中经常遇到的一种行为,这种行为对渠道成员和产品制造商的伤害极大。对窜货现象进行剖析后,我们可以看出,产生窜货的原因多种多样。很多学者都对窜货现象的形成原因作了分析并撰写了文章。他们对窜货的形成原因进行分析时大多是从产品、价格、分销和促销这四个方面进行分析的。本文在对窜货的形成原因进行分析时应用博弈理论对窜货现象进行了分析并在分析的基础上提出了如何预防和避免窜货现象的对策。     

环境监管中的博弈分析

通过建立环境监管问题的完全信息动态博弈模型,文章证明了在适宜的制度环境条件下,合谋可能是企业与地方政府的最优选择。针对优化制度环境,文章提出要加大来自上级政府的监督与制裁力度,改革地方政府的绩效考评制度等政策建议,以期改善地方环境状况。     

On core stability, vital coalitions, and extendability

If a TU game is extendable, then its core is a stable set. However, there are many TU games with a stable core that are not extendable. A coalition is vital if there exists some core element x such that none of the proper subcoalitions is effective for x. It is exact if it is effective for some core element. If all coalitions that are vital and exact are extendable, then the game has a stable core. It is shown that the contrary is also valid for matching games, for simple flow games, and for minimum coloring games.     

基于博弈论的企业品牌战略决策分析

博弈思维的全面导入,为企业品牌战略决策提供了重要的理论依据。由“非合作性博弈”向“合作性博弈”转换是当今国际市场主流发展趋势,市场主导企业与非主导企业结成品牌合作联盟,实施品牌合作战略,可以有效抵制外来企业的入侵,达到“双赢”的目的。