Competition with Congestible Networks

We analyse competition between two network providers when the quality of each network depends negatively on the number of customers connected to that network. With respect to price competition we provide a sufficient condition for the existence of a unique pure strategy Nash equilibrium. Comparative statics show that as the congestion effect gets stronger quantities will decrease and prices increase, under both Bertrand and Cournot competition. In an example with endogenous capacities it turns out that equilibrium capacities are at first increasing and then decreasing in the strength of congestion. Furthermore, capacities are higher under Cournot competition. Welfare comparisons between Bertrand and Cournot competition are unambiguous for fixed capacities, but may turn around for endogenous capacities.     

On strategic complementarity conditions in Bertrand oligopoly

Summary. For Bertrand duopoly with linear costs, we establish via a single (counter-)example that: (i) A new monotone transformation of the firms' profit functions may lead to the supermodularity of transformed profits when the standard log and identity transformations both fail to do so, and (ii) Topkis's notion of critical sufficient condition for monotonicity of a Bertrand firm's best-reply correspondence cannot be extended to rely only on positive unit costs. Received: January 16, 2001; revised version: March 20, 2002 RID="*" ID="*" This work was completed while the first author was visiting the Institute for Industrial Economics at the University of Copenhagen during Spring 2000. Their financial support and stimulating research environment are gratefully acknowledged. The views expressed here are those of the authors and should not be attributed to the European Commission. Correspondence to: R. Amir     

基于共生关系的创意产业集群形成机制——上海18个创意产业集群实证

以上海18个创意产业集群为分析对象,利用共生模型对创意产业集群之间的形成机制进行实证研究。研究结果表明,互利共生关系是创意产业集群形成的逻辑起点,互利共生关系越贴近于对称互利共生关系,则创意产业集群效应越好,从而越有利于创意产业集群的形成和稳定发展,且共生关系质量越好。     

产业集聚效应的系统动力学模型研究

以系统动力学理论为基础，结合产业集聚效应的正反馈特征，对人才流、技术流、资金流和市场流的因果关系进行了探讨。通过产业集聚效应衡量方法的比较，构建系统动力学模型，分析制约产业集聚效应发挥的主要因素，提出加强政府投资力度、发挥市场机制作用和提高企业整体能力的建议。     

Environmental Policy in Open Economies and Monopolistic Competition

This paper analyses the implications of international trade for non-cooperative environmental policy in the case of local production externalities. A particular focus is on the potential effects of regulations on the variety of goods and the resulting international spillover caused by trade. A tougher domestic standard negatively affects the utility of the households abroad, since such a policy reduces their variety of imports (due to fewer domestic product inventions) or their consumption of each imported brand (due to higher import prices). Ignoring the negative spillover, non-cooperative governments implement inefficiently strict standards in equilibrium. In contrast to this clear-cut inefficiency result, the impact of international trade on the state of the environment is ambiguous.     

外商投资对中国就业影响的实证分析

外商投资存在直接就业效应和间接就业效应，可以用外商投资流量和存量分别加以度量，运用中国1984～2005年的数据进行计量分析的结论表明：1993年以前外商投资的直接就业效应非常显著，负的间接就业效应也很显著；1993年以后年外商投资的直接就业效应减小。负的间接就业效应也减弱。     

Mixed Equilibrium in a Downsian Model with a Favored Candidate

This paper examines competition in the standard one-dimensional Downsian model of two-candidate elections, but where one candidate (A) enjoys an advantage over the other candidate (D). Voters' preferences are Euclidean, but any voter will vote for candidate A over candidate D unless D is closer to her ideal point by some fixed distance δ. The location of the median voter's ideal point is uncertain, and its distribution is commonly known by both candidates. The candidates simultaneously choose locations to maximize the probability of victory. Pure strategy equilibria often fail to exist in this model, except under special conditions about δ and the distribution of the median ideal point. We solve for the essentially unique symmetric mixed equilibrium with no-gaps, show that candidate A adopts more moderate policies than candidate D, and obtain some comparative statics results about the probability of victory and the expected distance between the two candidates' policies. We find that both players' equilibrium strategies converge to the expected median voter as A's advantage shrinks to 0. Journal of Economic Literature Classification Numbers: C72, D72.     

旅行社价格战的博弈分析

旅行社是旅游产品设计、组织和销售的渠道商以及消费者之间的桥梁.旅行社对旅游业具有重要影响，旅行社之间的价格竞争日益严重，盈利率低。随着我国加入世贸组织，越来越多的外国旅行社进入我国、针对我国旅行社如何走出困境，本文从博弈角度分析旅行社的价格竞争及其对策。     

Current Account, Capital Formation and Terms of Trade Shocks: a Revisit of the Harberger-Laursen-Metzler Effect

This paper extends the Blanchard model of a closed-economy to a three-good (exportable, importable and non-tradable goods) open-economy model with capital accumulation and uncertain lifetimes to study the impacts of terms of trade shocks on the current account. The simulation results show that a model with uncertain lifetimes is more appropriate to describe a small open economy like Taiwan at the steady-state equilibrium than a model with infinite lifetimes. We find that the Harberger-Laursen-Metzler effect is discernible for temporary or permanent terms of trade shocks. Furthermore, the steady state is a saddle point and the speed of convergence of capital and consumption is quite low.     

西方现代股利政策理论的演进与评价

股利政策是个谜。四十多年来,西方财务学者分别从不同的角度、运用不同的方法对股利政策进行了大量的理论和实证研究。本文对此进行了较为系统和全面的回顾与评述。早期股利理论研究主要集中在股利政策与股票价格是否有关的研究上,其观点主要有在手之鸟理论和股利无关论。20世纪八十年代后,股利之争主要集中在股利为什么会引起股票价格变化,其观点有追随者效应、信号理论、代理学说和行为学派等。虽然这些学派的观点在不同程度上还存在一些缺点,但它们改变了传统理论的思维方式和分析方法,极大地扩展了财务学的研究视野,从而使股利政策研究在“量”和“质”上均产生了很大的飞跃。