Endogenous uncertainty and the non-neutrality of money

Summary. We study some implications of the Theory of Rational Beliefs to monetary policy. We show that monetary policy in a Rational Beliefs environment can have an important effect on the characteristics of economic fluctuations. In Rational Beliefs Equilibria money is generically non-neutral unlike Rational Expectations Equilibria in which money is neutral and monetary policy is ineffective. Under Rational Beliefs Equilibria nominal prices and real output change not only in response to changes in the exogenous growth rate of money but also in response to changes in the state of beliefs. In Rational Beliefs Equilibria monetary shocks have real effects even when they are observed but are not fully anticipated. Furthermore, the non-neutrality of money results in a short run Phillips curve. When money “flutters, real output sputters” [8]. We show that Endogenous Uncertainty and the distribution of market beliefs are the major explanatory variables of such fluctuations. Under Rational Expectations monetary policy is ineffective because agents neutralize it by predicting correctly the effect of the policy. Under Rational Beliefs it is shown instead that inflation and recessions can be substantially aggravated by the distribution of market beliefs. Received: January 14, 2002; revised version: April 5, 2002 RID="*" ID="*" I would like to thank Mordecai Kurz for his constant help and support. Most of the ideas developed hereby have been inspired by innumerable and fruitful discussions with him. I have also greatly benefited from helpful comments by Stanley Black, Luigi Campiglio, Carsten Nielsen and Ho-Mou Wu. I also received valuable remarks from participants at the V meeting of “The Society for the Advancement of Economic Theory” held in Ischia, Italy, on July 2-8, 2001, where an initial draft of the present work was presented.     

Introduction to a General Equilibrium Approach to Economic Growth

Endogenous growth theory has had some success in explaining the observed data related to the process of economic growth. However, the results of the models in this literature are typically very sensitive to their micro-economic structure. It is therefore important to understand how the growth process behaves under more general specifications of such features as the number of commodities, the number and preferences of consumers, the factors of production, and the financial and information structures. In other words, valuable insights can be gained by integrating growth theory into the framework of general equilibrium theory. The summary of the papers in this volume, focuses on seven issues that are crucial to this integration and highlights the contributions of the papers to the resolution of these issues. Journal of Economic Literature Classification Numbers: C61, D50, D90, F43, O30, O41.     

质量信号的选择与潜在替代压力--对专业服务跨国公司进入中国市场初期策略的分析

专业服务跨国公司在市场进入初期,以质量信号作为歧异化战略的具体实施方式之一。文章在分离均衡条件下对其质量信号的选择策略进行了研究。选择何种质量信号,受到服务成本差异程度、来自相邻市场的替代压力和重复购买性等因素的制约。如果专业服务跨国公司提供服务的替代程度较低时,高价格会成为最优的质量信号。相反,如果相邻市场对细分市场有一定的替代压力时,花费性广告更有可能作为质量信号出现。文章据此对专业服务跨国公司的未来的质量信号策略和市场渗透方式作出了预测。     

Strategic pricing of equity issues

Summary. Consider a general equilibrium model where agents may behave strategically. Specifically, suppose some firm issues new shares. If the primary market price is controlled by the issuing institution and investors' expectations on future equity prices are constant in their share purchases, the share price on the primary market cannot exceed the secondary market share price. In certain cases this may imply strict underpricing of newly issued shares. If investors perceive an influence on future share prices overpriced issues may occur in equilibrium. This provides an example of strategic price manipulation in general equilibrium models with sequential markets. Received: March 14, 2000; revised version: May 15, 2001     

Existence and Welfare Properties of Equilibrium in an Exchange Economy with Multiple Divisible and Indivisible Commodities and Linear Production Technologies

In this paper we consider a class of economies with a finite number of divisible commodities, linear production technologies, and indivisible goods and a finite number of agents. This class contains several well-known economies with indivisible goods and money as special cases. It is shown that if the utility functions are continuous on the divisible commodities and are weakly monotonic both on one of the divisible commodities and on all the indivisible commodities, if each agent initially owns a sufficient amount of one of the divisible commodities, and if a “no production without input”-like assumption on the production sector holds, then there exists a competitive equilibrium for any economy in this class. The usual convexity assumption is not needed here. Furthermore, by imposing strong monotonicity on one of the divisible commodities we show that any competitive equilibrium is in the core of the economy and therefore the first theorem of welfare also holds. We further obtain a second welfare theorem stating that under some conditions a Pareto efficient allocation can be sustained by a competitive equilibrium allocation for some well-chosen redistribution of the total initial endowments. Journal of Economic Literature Classification Numbers: D4, D46, D5, D51, D6, D61.     

Nash equilibrium in games with incomplete preferences

Summary. This paper investigates Nash equilibrium under the possibility that preferences may be incomplete. I characterize the Nash-equilibrium-set of such a game as the union of the Nash-equilibrium-sets of certain derived games with complete preferences. These games with complete preferences can be derived from the original game by a simple linear procedure, provided that preferences admit a concave vector-representation. These theorems extend some results on finite games by Shapley and Aumann. The applicability of the theoretical results is illustrated with examples from oligopolistic theory, where firms are modelled to aim at maximizing both profits and sales (and thus have multiple objectives). Mixed strategy and trembling hand perfect equilibria are also discussed.Received: 22 September 2003, Revised: 24 June 2004, JEL Classification Numbers: D11, C72, D43.I would like to thank Jean-Pierre Benôit, Juan Dubra, Alejandrio Jofre, Debraj Ray, Kim-Sau Chung and the seminar participants at NYU and at the Universidad de Chile for their comments. I am most grateful to Efe Ok, for his comments, criticism, suggestions and questions.     

要素跨区域流动对区域经济增长和波动的影响探讨

要素跨区域流动对区域经济增长和波动的影响应是多方面的.首先是区域间贸易和要素流动规模的扩大,提高了国内区域经济发展的一体化程度,分散了区域性供给或需求波动对区域经济发展的整体冲击力并进而进一步强化了区域经济波动周期延长与强度下降的趋势.其次是要素流动规模的扩大不仅进一步拓宽了经济波动的区域间的传导渠道,而且也提高了区域间经济增长与波动的相互解释力,增强了彼此间的因果关系和减弱了彼此间的同步性.     

The potential for underinvestment in internet security: implications for regulatory policy

With the continuing growth of the use of the Internet for business purposes, the consequences of a possible cyber attack that could create a large scale outage of long time duration becomes a more and more serious economic issue. In this paper, we construct a game-theoretic model that addresses the economic motivations for investment in added Internet security and makes a case for a possible market failure in the form of underinvestment in the provision of Internet security. This result relies on the fact that the social value derived from consumption (which is at least equal to a fraction of the surplus derived from e-commerce) greatly exceeds the revenue at stake associated with the telecommunications companies’ and ISP’s security levels. If the ratio of social value to revenue at stake to Internet providers continues to grow, the likelihood of underinvestment in security becomes higher and some form of regulation may become necessary. We discuss the difficulties associated with designing and enforcing a regulatory scheme based upon mandatory security standards.      

CO2-Stabilization May Be a 'No-Regrets' Policy

Restricting CO₂ emissions requires changing today's consumption pattern away from energy and emission intensive commodities towards cleaner goods. The cost of stabilizing CO₂ emissions at the 1990 level by the year 2000, say, as compared to a business-as-usual trend, is estimated by several researchers to be on the order of 1% of GNP. We will argue that the cost may be overestimated because of a too simple model describing the working of the economic system and the evaluation of welfare. We demonstrate that by expanding a model to include the actual tax system and negative externalities, the cost to present generations from restricting emissions by a CO₂ tax may be negative. That is, some reduction may actually correspond to a 'no-regrets' policy. The reasons are inefficiencies in today's tax system and non-optimal handling of negative externalities. Our analysis suggests that a CO₂ tax and reduced emissions will lessen such inefficiencies.     

集中战略的博弈分析

企业的经营战略可分为成本领先战略、差异化战略以及集中战略。集中战略最突出的特点是企业专门服务于总体市场的一部分,对某一类型的顾客或某一地区性市场作密集性经营。本文拟运用博弈论的相关模型对集中战略进行分析。