The equilibrium manifold keeps the memory of individual demand functions

Summary. It is shown that the property that the equilibrium manifold keeps the memory of the individual demand functions holds true if every individual demand function satisfies the following three properties: 1) It is a function of commodity prices and of consumers income; 2) Consumption belongs to the nonnegative orthant of the commodity space; 3) Walras law. Neither differentiability nor continuity are necessary. In addition, the demand functions do not have to be utility maximizing subject to budget constraints.Received: 2 September 2003, Revised: 26 January 2004, JEL Classification Numbers: D50, D51.A preliminary version of this paper was released in October 1999 under the title Deriving individual demand functions from the equilibrium manifold. I wish to thank an anonymous referee for thoughtful comments.     

Ambiguity,uncertainty aversion and equilibrium welfare

Summary. In order to analyse the effect of ambiguity and uncertainty aversion on equilibrium welfare, a two period, pure exchange one good economy is considered. Agents are Choquet-expected-utility maximizers with same convex capacity and strictly concave utility index. It is proven that equilibrium is indeterminate whenever several probabilities in the core of the capacity minimize the expected value of aggregate endowment and not all agents have same expected endowments under those probabilities. It is further shown that small changes in aggregate endowment may have drastic welfare implications. A more general model is considered in the case of no aggregate uncertainty: agents have a set of priors and are uncertainty averse as modelled by Gilboa-Schmeidler [1989]. In the case of complete markets, it is shown that assets have a spread of equilibrium prices similar to the spread of no-arbitrage prices compatible with absence of arbitrage in markets with imperfections.Received: 2 June 2000, Revised: 27 March 2003, JEL Classification Numbers: D46, D59,D60, G12.I have benefited from conversations with L. Epstein, F. Magnien and J. M. Tallon.     

Mistaken self-perception and equilibrium

Summary. Motivated by real-world information economics problems and by experimental findings on overconfidence, this paper introduces a general epistemic construction to model strategic interaction with incomplete information, where the players self-perception may be mistaken. This allows us to rigorously describe equilibrium play, by formulating appropriate equilibrium concepts. We show that there always exist objective equilibria, where the players correctly anticipate each others strategies without attempting to make sense of them, and that these outcomes coincide with the equilibria of an associated Bayesian game with subjective priors. In population games, these equilibria can also be always introspectively rationalized by the players, despite their possibly mistaken self-perception.Received: Received: May, 12, 2003; revised version: 3 December 2004, Revised: 3 December 2004, JEL Classification Numbers: J31, D82, D83.I thank Massimiliano Amarante, Eddie Dekel, Massimo Marinacci, Jean Francois Mertens, Giuseppe Moscarini, Paolo Siconolfi, Marciano Siniscalchi, Joel Sobel, and an anonymous referee.     

Identification of consumers’ preferences when their choices are unobservable

Summary. We provide conditions under which the heterogenous, deterministic preferences of consumers in a pure exchange economy can be identified from the equilibrium manifold of the economy. We extend those conditions to consider exchange economies, with two commodities, where consumers preferences are random. For the latter, we provide conditions under which consumers heterogenous random preferences can be identified from the joint distribution of equilibrium prices and endowments. The results can be applied to infer consumers preferences when their demands are unobservable.Received: 8 May 2003, Revised: 14 September 2004, JEL Classification Numbers: D12, D51.I am very grateful to an anonymous referee, Donald Brown, and Daniel McFadden for their detailed comments and insightful suggestions. Section 2 of this paper is joint work with Donald J. Brown; it is included here for publication with his permission. Those results were presented at the 1990 Workshop on Mathematical Economics at the University of Bonn, the 1992 SITE Workshop on Empirical Implications of General Equilibrium Models at Stanford University, and, more recently, at the June 2000 Conference in Honor of Rolf Mantel, in Buenos Aires, Argentina. The comments of the participants at those conferences and workshops are much appreciated. The research presented in this paper was supported by NSF Grants SES-8900291, SBR-9410182, and SES-0241858. This paper is dedicated to Marcel K. Richter, who has inspired much of my research.     

Continuity of the equilibrium price density and its uses in peak-load pricing

Summary. With as the commodity space, the equilibrium price density is shown to be a continuous function of the commodity characteristics. The result is based on symmetry ideas from the Hardy-Littlewood-Pólya theory of rearrangements. It includes, but is not limited to, the case of symmetric (rearrangement-invariant) production costs and additively separable consumer utility. Examples arise in continuous-time utility pricing, e.g., electricity pricing. In this context, a continuously varying price has two uses. First, it precludes demand jumps that would arise from discontinuous switches from one price rate to another. Second, in the problems of operating and valuing hydroelectric and pumped-storage plants (studied elsewhere), price continuity guarantees that their capacities (viz., the reservoir and the converter), the energy stocks, and in the case of hydro also the river flows, have well-defined marginal values.Received: 9 May 2001, Revised: 8 July 2004, JEL Classification Numbers: C62, D51, D58, L94. Correspondence to: Anthony HorsleyPart of this work (CentER DP 9014) was completed at the Center for Economic Research, Tilburg University, whose financial support is gratefully acknowledged. The extension to storage was supported by ESRC grant R000232822. We also thank the referee and the editor for their comments.     

一般均衡理论的价值基础

现代西方主流经济学中的一般均衡理论缺乏应有的价值基础。近年来试图建立马克思主义的一般均衡理论的努力也一直未能成功。然而,根据马克思的劳动价值论可以证明,在假定社会总产品的价格总量等于价值总量、平均利润总量等于剩余价值总量的条件下,必然有且仅有一个恰好等于相应价值向量的一般均衡价格向量。这意味着,一般均衡理论完全可以建立在劳动价值论的基础之上。本文首先根据马克思关于两大部类社会总产品构成的理论,建立包括技术关系在内的价值体系和相应的价格体系,其次说明在价格体系中存在有无穷多的一般均衡价格向量,最后从无穷多的一般均衡价格向量中确定一个"标准"的价格向量,并证明这个标准价格向量必然等于相应的价值向量。     

人民币汇率的均衡与失调

人民币汇率波动趋势表现出了"U"型特征,推动其升值的主要因素是经常项目盈余导致的净对外资产余额的不断增加、FDI资本的大量流入和贸易品部门劳动生产率的较快提高。人民币均衡汇率在1985年～1989年表现为高估,在1990年～2009年表现为低估。人民币均衡汇率低估具有逐渐收敛的特征,从而人民币均衡汇率继续升值的空间已经很小了。人民币汇率机制的完善不仅要考虑到影响汇率的主要因素,也要考虑潜在因素。     

政府和企业对产业共性技术两种研发投资类型的比例研究

基于产业共性技术研发在新形势下经济转型升级中的战略意义以及共性技术研发投资的“死亡谷”效应,构建了政府和企业两个投资主体、预研投资和研发投资两种投资类型的柯布道格拉斯生产函数（CD生产函数）投资博弈模型。通过最优反应函数求解,得到不同政府预算占比情况下共性技术研发投资的纳什均衡,探索了政府和企业对两种投资的最优比例,并通过案例分析验证了模型的有效性。结果发现,政府在产业共性技术投资供给中更倾向于预研投资,企业在产业共性技术投资供给中更倾向于研发投资;政府应根据产业发展不同阶段,适时调整功能定位,针对产业共性技术研发投资,动态调整支持方式和支持力度。     

Advancing economic analysis beyond the equilibrium framework

Twentieth century economics was dominated by the development and refinement of the concept of economic equilibrium. While it is worthwhile to understand the properties of economic equilibrium, equilibrium concepts have dominated economic thought to the point that they have obscured some of the more important issues economists have always strived to understand. At least since Adam Smith’s time, economists have tried to understand the causes of prosperity, and how economic welfare can be enhanced, but these issues are best understood outside the equilibrium framework. The foundations provided by the Austrian school point toward ways that economic analysis can expand beyond the equilibrium framework.

Pollution abatement with disruptive R&D investment

This paper examines a model of investment in abatement where polluting firms produce output while investing in R&D. This investment, however, increases production costs, thus disrupting first-period output. We identify three equilibrium profiles where firms choose to either: (1) invest in R&D alone (thus rationalizing a common modeling assumption in the literature); (2) produce output alone; or (3) engage in both activities. We evaluate how the emergence of each result is affected by the market structure in which firms compete and by the severity of spillover effects. We then measure welfare levels in each equilibrium profile. Overall, we show that firms endogenously choose to focus on R&D only when the market is concentrated and spillover effects are small. In other type of industries, our findings indicate that firms may focus on output production or engage in both activities under relatively large conditions.     

均衡与演化——对经济学发展方向的思考

经济学研究中的均衡主义与演化主义历来存在争论.本文在对经济均衡主义和演化主义的形成、内容及特征详细分析的基础上,对经济学体系的发展状况进行了初步的检讨.本文认为,对均衡主义与演化主义在一个更为一般的框架内进行整合和创造性发展,具有重大的理论价值.     

Does the invisible hand hold or lead? Market adjustment in an entrepreneurial economy

Adam Smith's “invisible hand” is one of the best-known phrases in economics, but its meaning is somewhat ambiguous. The invisible hand might be viewed as holding the economy close to equilibrium, yet Smith actually says that individuals are led by an invisible hand. Entrepreneurial forces lead an economy along a path that generates economic progress, and that path is determined by the disruptive forces of entrepreneurship. Rather than viewing an economy as tending toward an equilibrium, it is more accurate to view an economy as characterized by continuing progress, led by the invisible hand of entrepreneurial activity. JEL Code B53, D21, E32, O31     

The local best response criterion: An epistemic approach to equilibrium refinement

The standard refinement criteria for extensive form games, including subgame perfect, perfect, perfect Bayesian, sequential, and proper, reject important classes of reasonable Nash equilibria and accept many unreasonable Nash equilibria. This paper develops a new refinement criterion, based on epistemic game theory, that captures the concept of a Nash equilibrium that is plausible when players are rational. I call this the local best response (LBR) criterion. This criterion is conceptually simpler than the standard refinement criteria because it does not depend on out-of-equilibrium, counterfactual, or passage to the limit arguments. The LBR is also informationally richer because it clarifies the epistemic conditions that render a Nash equilibrium reasonable. The LBR criterion appears to render the traditional refinement criteria superfluous.     

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.     

产业平衡态与产业有序发展的内在思考

深入阐述了以热力学原理解释产业发展过程的基本思路,引入熵的理念,结合经典燃烧理论,将产业温度用于模拟产业系统走向劣质化的基本表达,企图弥补哈肯和普利高津对系统如何从有序走向无序部分缺失的遗憾。在此基础上,围绕产业非线性与非平衡性,给出了产业运行正负熵流机制及其定量化公式表达,采用产业温度曲线刻画产业系统动态衍生过程,较为完整地勾勒出从“自然关系”到“逻辑关系”再到“函数关系”的内在科学理论体系。     

An evolutionary model of speculative attacks

We build an evolutionary model of currency crises incorporating learning through imitation and experimentation by heterogeneous agents. Foreign currency speculators in the model interact and learn over time through experimentation. Drawing on results from game theory, we show that the resulting dynamic converges to a unique long run equilibrium, in which the currency is “attacked” if the economic fundamentals are sufficiently adverse. Evolutionary selection is thus shown as a way to resolve the issue of indeterminacy of equilibria associated with models of currency crises.JEL Classification: C63, F31, D83, C72I am grateful to Jasmina Arifovic, Peter Garber, Pravin Krishna, Blake LeBaron, Nidhiya Menon, Srinivas Thiruvadanthai and Tiemen Woutersen for useful remarks and suggestions. All errors remain my own.     

人民币均衡汇率与汇率失调:1991-2004

本文运用行为均衡汇率模型对人民币均衡实质汇率和汇率失调程度进行了实证研究,样本区间为1 991年1季度—2 0 0 4年3季度。本文的主要发现是:( 1 )从1 994年4季度起人民币均衡实质汇率处于不断升值的状态,其背后的主要驱动力量是我国制造业劳动生产率的快速上升和经常项目盈余导致的净对外资产余额的不断增加;( 2 ) 2 0世纪90年代以来,人民币实际实质汇率在大部分时期偏离均衡实质汇率轨迹,表现为人民币汇率的失调。其中,1 992年2季度—1 994年4季度为人民币汇率低估时期,1 995年1季度—1 999年2季度为人民币汇率高估时期,而1 999年3季度往后的时期人民币汇率重新转为低估,并且低估程度有进一步扩大的趋势。本文对人民币汇率失调的原因分析表明1 997年以来硬钉住美元的汇率政策是造成人民币汇率失调的一个主要宏观政策因素。因此,本研究的政策含义是,从应对人民币汇率失调的角度,更为灵活的汇率政策将更有利于中国经济的稳定健康发展     

An evolutionary theory of the convergence towards low inflation rates

This paper presents an evolutionary interpretation of Barro-Gordons monetary policy game. The model describes a multi-country setup where governments and private agents are boundedly rational players. The behavioral rule of players decisions leads to the imitation of the strategy giving the highest payoff. In this evolutionary monetary policy game, we show how a low inflation state is reached from an international context dominated by inflationary policies. The analysis explains the convergence towards low inflation rates observed during the past twenty years. Moreover, the low inflation state appears to be the long-run equilibrium of the game under some conditions featuring the observed macroeconomic context.JEL Classification: E5, C72, C73 Correspondence to: A. dArtigues     

Equilibrium selection in common-value second-price auctions

This note considers equilibrium selection in common-value second-price auctions with two bidders. We show that for each ex post equilibrium in continuous and undominated strategies, a sequence of “almost common-value” auctions can be constructed such that each of them possesses a unique undominated and continuous equilibrium and the corresponding sequence of equilibria converges to that ex post equilibrium. As an implication, no equilibrium selection of this model based on perturbations seems to be more convincing than others.