Optimal investment with vintage capital: Equilibrium distributions

The paper concerns the study of equilibrium points, or steady states, of economic systems arising in modeling optimal investment with vintage capital, namely, systems where all key variables (capitals, investments, prices) are indexed not only by time but also by age. Capital accumulation is hence described as a partial differential equation (briefly, PDE), and equilibrium points are in fact equilibrium distributions in the variable of ages. A general method is developed to compute and study equilibrium points of a wide range of infinite dimensional, infinite horizon, optimal control problems. We apply the method to optimal investment with vintage capital, for a variety of data, deriving existence and uniqueness of equilibrium distribution, as well as analytic formulas for optimal controls and trajectories in the long run. The examples suggest that the same method can be applied to other economic problems displaying heterogeneity. This shows how effective the theoretical machinery of optimal control in infinite dimension is in computing explicitly equilibrium distributions. To this extent, the results of this work constitute a first crucial step towards a thorough understanding of the behavior of optimal paths in the long run.     

Efficient Liability Rules: Complete Characterization

Received May, 18, 2000; revised version received March, 19, 2001     

人民币实际汇率失调与中国国际竞争力

本文首先测算了1994年第一季度到2005年第二季度的人民币均衡实际汇率及人民币实际汇率的失调程度,然后考察了这一时期人民币实际汇率失调与中国国际竞争力之间的关系。通过研究发现:这一时期的人民币实际汇率失调与中国国际竞争力之间存在负相关关系,并且人民币实际汇率失调是导致中国国际竞争力变化的格兰杰原因,具体来说,人民币实际汇率高估会导致中国国际竞争力下降。     

中日韩自由贸易区的贸易流量和福利效应分析:一个局部均衡的校准方法

校准方法作为一种确定数理经济模型中的变量和参数的手段之一,在贸易政策的建模研究中得到广泛的应用.本文以局部均衡为基础,利用中日韩三国自1990～2003年共14年的贸易额及相关数据建立校准模型,并对拟议中的中日韩自由贸易区做出比较静态分析,从产业层面来模拟中日韩自由贸易区建成后所可能带来的福利效应.分析结果表明,中日韩三国建立自由贸易区会增加彼此的国民福利水平,并会对未加入贸易协定的其他东亚国家产生影响.因此,在东亚形成更为广泛的自由贸易安排从区域合作的角度来看是一种更佳的合作方式.     

区域经济学主流化的新格局:迈向新综合的空间一般均衡理论

区域经济学的研究从1990年后，日趋活跃、争论纷呈，在某种意义上讲，发生了很大的转向。即由克鲁格曼发轫的新经济地理把该领域的某些问题带向经济学主流的一般均衡分析框架下来讨论，他们更加宏伟的蓝图是要实现具有新综合特征的空间一般均衡理论，为区域经济学的研究注入了新的活力。该文简述了这些新理论的基本模型、主要特征和模型的扩展及对经济体系空间特性研究的主要贡献，以及由之而引起的各方面的争论和共识。     

Self-enforcing international environmental agreements with a stock pollutant

In this paper the stability of an International Environmental Agreement (IEA) among N identical countries that emit a pollutant are studied using a two-stage game. In the first stage each country decides noncooperatively whether or not to join an IEA, and in the second stage signatories jointly against nonsignatories determine their emissions in a dynamic setting defined in continuous time. A numerical simulation shows that a bilateral coalition is the unique self-enforcing IEA independently of the gains coming from cooperation and the kind of strategies played by the agents (open-loop or feedback strategies). We have also studied the effects of a minimum participation clause finding that for this case a self-enforcing IEA just consists of the number of countries established in the clause.JEL Classification: C73, D62, Q28 Corresponding author : Santiago J. RubioThis paper is based on chapter four of Begoña Casinos Ph. Dissertation. Financial support from the Instituto Valenciano de Investigaciones Económicas, the Ministerio de Ciencia y Tecnología under grant BEC2000-1432 and Fundación BBVAis gratefully acknowledged. We also appreciate the helpful comments of three anonymous referees, whose suggestions improved the paper. Regarding any remaining inadequacies, the usual caveat applies.     

博弈论在治理河流水污染中的应用

针对我国日益严重的河流水污染状况，本文通过对污染源企业和政府之间的关系进行博弈分析，建立监督博弈模型，并以此分析政府对污染源企业的监管力度及经济上的处罚力度。     

投资决策中个人理性与集体理性博弈分析及对策研究

针对近期多起曝光的企业对外投资、担保大案,本文应用博弈论分析方法,在强调个人理性与集体理性矛盾的基础上研究投资决策中两者的完全信息博弈及无限阶段重复博弈,并建立相应的定量分析模型,通过分析博弈参与人均衡行为,指出投资决策中寻租的存在的必然性及巨大危害,并针对性的提出了适合实际操作的对策建议.     

独立审计质量的经济学透视

本文从需求和供给两方面分析了独立审计市场中的审计质量均衡状况及其成因,研究发现:一方面,由我国公司治理不完善而引发的对独立审计的代理需求不足,以及特定融资制度下对低质量审计的融资需求强劲,使得我国独立审计的自愿性需求严重匮乏,从而审计师缺乏提高审计质量的内在经济动机;另一方面,现有法规对审计师的激励不足、约束不够,因此目前审计师提供的审计服务质量难于达到社会公众的期望-《独立审计准则》的要求.最后,笔者针对出现的问题提出相应的政策建议.     

Playing safe in coordination games:: the roles of risk dominance, payoff dominance, and history of play

This paper presents results from a series of experiments designed to test the impact on subject behavior of changes in the risk dominance and payoff dominance characteristics of two player coordination games. The main finding is that changes in risk dominance significantly affect play of the subjects, whereas changes in the level of payoff dominance do not. Observed history of play also has an important influence on subject behavior, both when subjects are randomly rematched after each game and when they remain matched with the same individual for a sequence of games.