Continuous-time games of timing

We address the question of existence of equilibrium in general timing games with complete information. Under weak assumptions, any two-player timing game has a Markov subgame perfect -equilibrium, for each >0. This result is tight. For some classes of games (symmetric games, games with cumulative payoffs), stronger existence results are established.     

Mixed-strategy equilibria and strong purification for games with private and public information

This paper shows the existence of mixed-strategy equilibria for games with private and public information under general conditions. Under the additional assumptions of finiteness of action spaces and diffuseness and conditional independence of private information, a strong purification result is obtained for the mixed strategies in such games. As a corollary, the existence of pure-strategy equilibria follows. I am very grateful to Yeneng Sun, Nicholas C. Yannelis and M. Ali Khan for helpful discussions and suggestions. I also wish to thank an anonymous referee whose comments led to many improvements in the paper.     

The nucleolus of large majority games

Members of a shareholder meeting or legislative committee have greater or smaller voting power than meets the eye if the nucleolus of the induced majority game differs from the voting weight distribution. We establish a new sufficient condition for the weight and power distributions to be equal, and we characterize the limit behavior of the nucleolus in case all relative weights become small.     

Weak measurability and characterizations of risk

Summary. In the context of a continuum of random variables, arising, for example, as rates of return in financial markets with a continuum of assets, or as individual responses in games with a continuum of players, an important economic issue is to show how idiosyncratic risk can be removed through some device of aggregation or diversification when such risk is explicitly introduced into the model. In this paper, we use recent work of Al-Najjar [1] as a general backdrop to provide a review of the basic issues involved when the continuum is formulated as the Lebesgue interval. We present two examples to argue that the fundamental problem of the non-measurability of sample functions, originally identified by Doob, and further elaborated by Feldman, Gilles and Judd in the economic literature, simply cannot be bypassed by reinterpretations of standard results. We also provide an equivalence result in the spirit of Al-Najjar's efforts; but argue that this elementary result does not go beyond the standard law of large numbers for a sequence of real-valued iid random variables, and as such, is incapable of yielding anything of substantive economic interest beyond this law. Received: April 23, 1998; revised version: April 28, 1998     

A remark on the equilibrium set of pureexchange economies

Summary.  We present a unified mathematical framework within which, among others, pure exchange economies with a finite set of agents, as well as those with a continuum of traders may be studied simultaneously. We prove that the reasoning presented by Balasko (1975) on the equilibrium set for finite economies generalizes very naturally to our setting. His results may therefore be recovered as a special case of those presented in this note. Received: April 9, 1996; revised version August 19, 1996     

On the existence of pure-strategy equilibria in large games

Over the years, several formalizations and existence results for games with a continuum of players have been given. These include those of Schmeidler [D. Schmeidler, Equilibrium points of nonatomic games, J. Stat. Phys. 4 (1973) 295-300], Rashid [S. Rashid, Equilibrium points of non-atomic games: Asymptotic results, Econ. Letters 12 (1983) 7-10], Mas-Colell [A. Mas-Colell, On a theorem by Schmeidler, J. Math. Econ. 13 (1984) 201-206], Khan and Sun [M. Khan, Y. Sun, Non-cooperative games on hyperfinite Loeb spaces, J. Math. Econ. 31 (1999) 455-492] and Podczeck [K. Podczeck, On purification of measure-valued maps, Econ. Theory 38 (2009) 399-418]. The level of generality of each of these existence results is typically regarded as a criterion to evaluate how appropriate is the corresponding formalization of large games.In contrast, we argue that such evaluation is pointless. In fact, we show that, in a precise sense, all the above existence results are equivalent. Thus, all of them are equally strong and therefore cannot rank the different formalizations of large games.     

A longitudinal assessment on the economic effects of hosting major sporting events

Hosting major sporting events (MSEs) has become a globalized strategy for many countries. This paper is to incorporate event study and dynamic panel data analysis with annual secondary data to examine and clarify the long-term economic effects of host countries that had hosted the Asian Games and the Olympic Games from 1950 to 2014. The results indicate that hosting MSEs to create positive economic effects like the real economic growth rate, investment, employment and international trade may be a myth even for developing countries. The evidences can provide the sport management or authority with longitudinal and comprehensive elaboration for biding or hosting MSEs in the future.     

奥运会与通货膨胀的机理研究

奥运会是否会引发举办地的通货膨胀问题，一直是事件研究领域内争论的问题，实证研究的结果也存在差异性。本文从经济学理论的角度分析和研究了奥运会引发通货膨胀的可能性，指出奥运会引发通货膨胀的根源在于奥运会的刚性引至性需求增加导致奥运周期内资源供给的不足，并提出了在奥运周期内适度增加供给的原则，这对奥运会举办地房地产价格上涨的研究具有一定理论和现实参考意义。     

A geometric approach to the price of anarchy in nonatomic congestion games

We present a short, geometric proof for the price-of-anarchy results that have recently been established in a series of papers on selfish routing in multicommodity flow networks and on nonatomic congestion games. This novel proof also facilitates two new types of theoretical results: On the one hand, we give pseudo-approximation results that depend on the class of allowable cost functions. On the other hand, we derive stronger bounds on the inefficiency of equilibria for situations in which the equilibrium costs are within reasonable limits of the fixed costs. These tighter bounds help to explain empirical observations in vehicular traffic networks. Our analysis holds in the more general context of nonatomic congestion games, which provide the framework in which we describe this work.     

A note on the one-deviation property in extensive form games

In an extensive form game, an assessment is said to satisfy the one-deviation property if for all possible payoffs at the terminal nodes the following holds: if a player at each of his information sets cannot improve upon his expected payoff by deviating unilaterally at this information set only, he cannot do so by deviating at any arbitrary collection of information sets. Hendon et al. (1996. Games Econom. Behav. 12, 274–282) have shown that pre-consistency of assessments implies the one-deviation property. In this note, it is shown that an appropriate weakening of pre-consistency, termed updating consistency, is both a sufficient and necessary condition for the one-deviation property. The result is extended to the context of rationalizability.     

Incentives in market games with asymmetric information: the core

Summary. This paper examines the ex ante core of a pure exchange economy with asymmetric information in which state-dependent allocations are required to satisfy incentive compatibility. This restriction on players' strategies in the cooperative game can be interpreted as incomplete contracts or partial commitment. An example is provided in which the incentive compatible core with nontransferable utility is empty; the game fails to be balanced because convex combinations of incentive compatible net trades can violate incentive compatibility. However, randomization of such strategies leads to ex post allocations which satisfy incentive compatibility and are feasible on average. Hence, convexity is preserved in such a model and the resulting cooperative games are balanced. In this framework, an incentive compatible core concept is defined for NTU games derived from economies with asymmetric information. The main result is nonemptiness of the incentive compatible core. Received: December 26, 2001; revised version: June 11, 2002 RID="*" ID"*" This work was financed, in part, by contract No 26 of the programme “P?le d'attraction interuniversitaire” of the Belgian government, and, in part, by research grant SBR93-09854 from the U.S. National Science Foundation. Much of my thinking about this topic was developed during a wonderful visit to CORE for the 1991–1992 academic year (on sabbatical from the University of Pennsylvania). This paper was originally circulated in December 1991 as CARESS Working Paper #91-38, Center for Analytic Research in Economics and the Social Sciences, Department of Economics, University of Pennsylvania and in February 1992 as CORE Discussion Paper 9221, Center for Operations Research and Econometrics, Université Catholique de Louvain, Louvain-la-Neuve, Belgium. RID="*" ID="*" At the very start of my research, Jean-Fran?ois Mertens was almost a co-author. Fran?ois Forges provided detailed comments at a later stage, during my visit to THEMA, Université Cergy-Pontoise, in Spring 1997. They are entitled to the customary disclaimer.     

Contests with a stochastic number of players

We study Tullock's (1980) n-player contest when each player has an independent probability 0 < p 1 of participating. A unique symmetric equilibrium is found for any n and p and its properties are analyzed. In particular, we show that for a fixed n > 2 individual equilibrium spending as a function of p is single-peaked and satisfies a single-crossing property for any two different numbers of potential players. However, total equilibrium spending is monotonically increasing in p and n. We also demonstrate that ex-post over-dissipation is a feature of the pure-strategy equilibrium in our model. It turns out that if the contest designer can strategically decide whether to reveal the actual number of participating players or not, then the actual number of participants is always revealed.     

A differentiable homotopy to compute Nash equilibria of n-person games

Summary. The literature on the computation of Nash equilibria in n-person games is dominated by simplicial methods. This paper is the first to introduce a globally convergent algorithm that fully exploits the differentiability present in the problem. It presents an everywhere differentiable homotopy to do the computations. The homotopy path can therefore be followed by several numerical techniques. Moreover, instead of computing some Nash equilibrium, the algorithm is constructed in such a way that it computes the Nash equilibrium selected by the tracing procedure of Harsanyi and Selten. As a by-product of our proofs it follows that for a generic game the tracing procedure defines a unique feasible path. The numerical performance of the algorithm is illustrated by means of several examples. Received: December 21, 1999; revised version: December 27, 2000     

贸易结算货币的新选择:稳定的篮子货币——对“金砖五国”货币合作的探讨

文章研究金砖五国货币合作的可能形式,构建了稳定的篮子货币作为贸易结算货币,为货币合作提供政策建议。文章首先考察了汇率之间的关系,认为一种货币的加权几何平均汇率能够消除不同货币表示币值的差异,在此基础上构建了篮子货币指数;其次研究了篮子货币波动最小的货币权重的选取,通过最优化方法获得最优权重;最后模拟计算了金砖五国篮子货币的权重,并探讨了如何把篮子货币最优权重转化为具体的货币篮子,同时给出了篮子货币和各国货币之间的汇率关系。     

Dealing with the dynamics of technology roadmapping implementation: A case study

Nowadays, companies are facing many challenges. The product life cycle is getting shorter while the complexity and the demand for product customization are increasing. Technology Roadmapping (TRM) has been widely used as a strategic management tool to help organizations in effectively identifying potential products or services for the future, determining proper technology alternatives, and mapping them with resource allocation plans. With the completion of TRM implementation, any organization can be assured that its required technologies and infrastructures will be ready when needed. Implementing TRM as a part of the ongoing strategic/business planning process is challenging because it may affect the organizational work process, structure, and culture. Therefore, an organization needs to understand how the changing roles and responsibilities of key players involved in the TRM process match with the dynamics of TRM implementation in each stage. This paper illustrates the dynamics of TRM implementation and presents a case study to demonstrate how one of the leading building product manufacturers in the ASEAN region went through the process.     

中小企业联保贷款的信誉博弈分析

本文在考察中小企业的违约信用成本、群体特点、经营环境的基础上,构建了一个中小企业联保贷款的信誉博弈分析框架,讨论了银行如何通过设置信誉成本将银行与企业之间的贷款—还款博弈转化为联保贷款成员企业之间的信誉博弈来降低信用风险的机制。研究结果表明:有效的信誉成本是开展中小企业联保贷款的制度基础;信誉成本主要体现为企业违约后丧失联保企业集团内部交易资格所引致的机会成本;银行的激励条件内生地决定了联保贷款的市场风险边界;银行在开展多元联保贷款时需要在拓展市场风险阈值和潜在信用风险之间进行权衡,以确定最佳的联保贷款成员规模。     

A cooperative study of one-commodity market games

A competitive model is attached to a particular market where several agents trade a same commodity. We focus on the stability of the price systems and define a solution concept, akin to the core, proving an existence result. The author wishes to thank the Editor and an anonymous referee for useful comments and remarks.     

基于交通改善的县域旅游空间结构研究——以炎陵县为例

根据炎陵县的旅游发展现状和旅游资源分布情况,结合交通状况的改变,对炎陵县县域内外的旅游空间结构重新进行判断,提出了“一心,两轴,三组团”,将县域外的旅游空间结构抽象为“十字形”空间布局,按照三种旅游资源类型进行整合,重点打造宗教朝拜、红色爱国、森林生态旅游三类旅游,提升炎陵县的旅游名气,为炎陵县旅游的独立发展打下坚实基础。