A PRIMER ON MATHEMATICAL MODELLING IN ECONOMICS

Abstract The Commission on Graduate Education in Economics had raised several concerns regarding the role of mathematics in graduate training in economics ( Krueger, 1991 ; Colander, 1998, 2005 ). This paper undertakes a detailed scrutiny of the notion of a utility function to motivate and describe the common patterns across mathematical concepts and results that are used by economists. In the process one arrives at a classification of mathematical terms which is used to state mathematical results in economics. The usefulness of the classification scheme is illustrated with the help of a discussion of Arrow's impossibility theorem. Common knowledge of the patterns in mathematical concepts and results could be effective in enhancing communication between students, teachers and researchers specializing in different sub‐fields of economics.     

知识溢出、产业集群与企业选址

由于知识的外部性,知识溢出这个新的区位因子正逐渐构成企业空间竞争的新变量,成为企业选址的关键因素之一。企业是否选址产业集群,实质上是对集群内知识溢出所带来的正负效应的权衡。一方面,知识溢出具有典型的局域性特征,吸引企业选址同一区域,强化了集群现象;另一方面,作为知识溢出载体的产业集群,通过本地生产网络、合作创新、人才流动、非正式交流等机制促进了知识的流动,在为企业减少创新成本的同时,也增加了集群内企业知识损失的风险。因此,不同特征的企业有不同的选址行为:处于学习和模仿创新阶段的中小企业趋于选址集群内,但是对具有一定规模和较强研发技术能力的企业而言,为了防止信息的泄露,往往定位于集群之外。     

Afriat’s theorem for indivisible goods

We identify a natural counterpart of the standard GARP for demand data in which goods are all indivisible. We show that the new axiom (DARP, for “discrete axiom of revealed preference”) is necessary and sufficient for the rationalization of the data by a well-behaved utility function. Our results complement the main finding of Polisson and Quah (2013), who rather minimally modify the original consumer problem with indivisible goods so that the standard GARP still applies.     

外资酒店进入中国的投资区位选择

中国酒店业保持快速跨越式发展势头的重要驱动因素之一是跨国酒店集团在中国的扩张与发展。本文的目的在于分析决定跨国酒店集团区位选择的因素,并且评价跨国酒店集团投资战略中区位选择的影响因素。本文分别以入境旅游人次、旅游者花费、实际吸收外商直接投资金额衡量的市场需求和市场规模、以人均 GDP衡量的商业环境,和以政策及重大节庆活动代表的虚拟变量检验其是否是影响酒店集团投资区位选择的重要因素。这对跨国酒店集团未来投资区位选择具有重要的借鉴价值。     

监管科技的发展挑战与中国选择：基于金融科技监管视角

金融科技促进了金融行业的创新发展,也带来了金融风险与金融监管的变化。在金融科技创新、风险与监管的内在逻辑下,监管科技犹如\"创新之帆\"下的\"灯塔\",历经了三次发展演进:从加强技术层的监管应用到监管数据报送的自动化,并进一步发展至以数据为中心的算法监管。全球监管科技发展背景下,尽管我国监管科技历经萌芽期与发展期,但是仍然面临着发展动能不足、监管理念落后、监管模式传统等挑战。我国可借鉴英国、美国与新加坡的监管科技发展经验,并结合本土化国情,构建起中国监管科技生态体系,转变监督理念,创新监管科技模式。     

Skill uncertainty and social inference

Research in psychology indicates that individuals often make inferences regarding unknown individual qualities based on potentially irrelevant (but socially observable) information. This paper explores occupational choices when individuals receive imprecise signals regarding ability and use the observable characteristics of previously successful individuals to infer own ability. Individuals who fail to observe successful predecessors of their same type may underestimate their potential for success in the occupation. We discuss the role of these biases in light of the literature on affirmative action and firm incentives.     

论“律师伪证罪”

文章分析了"律师伪证罪"的构成要件及对律师刑事辩护和国家法治形象的深刻危害,在此基础上提出了取消律师伪证罪的法律意见。     

Harsanyi’s theorem without the sure-thing principle: On the consistent aggregation of Monotonic Bernoullian and Archimedean preferences

This paper studies the extension of Harsanyi’s theorem (Harsanyi, 1955) in a framework involving uncertainty. It seeks to extend the aggregation result to a wide class of Monotonic Bernoullian and Archimedean preferences (Cerreia-Vioglio et al., 2011) that subsumes many models of choice under uncertainty proposed in the literature. An impossibility result is obtained, unless we are in the specific framework where all individuals and the social observer are subjective expected utility maximizers sharing the same beliefs. This implies that non-expected utility preferences cannot be aggregated consistently.     

员工建言发生和领导者建言采纳:权力感的视角

员工建言对组织决策、创新和绩效有着重要的影响。这些积极作用的发挥取决于两个重要过程:员工建言发生和领导者建言采纳。本文从权力感视角出发,探究了权力感对员工建言发生和领导者建言采纳的影响机制。本文主要包括三部分内容:一是员工权力感促进建言想法形成(员工建言发生的第一阶段)的机制研究;二是员工权力感促进其建言表达(员工建言发生的第二阶段)的机制研究;三是领导者权力感对其建言采纳的影响机制。本研究在理论上完善和拓展了权力感视角下的建言研究,在实践上为组织管理员工建言提供了借鉴意义。     

The Pazner-Schmeidler social ordering: A defense

It is shown that the Pazner-Schmeidler social ordering appears as a very natural solution to the problem of defining social preferences over distributions of divisible goods. The paper analyses various ways of deriving this social ordering from minimally egalitarian conditions and informational parsimony requirements.Received: 10 October 2003, Accepted: 4 April 2005, JEL Classification: D63, D71This paper was written while I was a research fellow at the ZiF (Bielefeld), for the project “Procedural Approaches to Conflict Resolution”, and the last version was prepared during my sabbatical year at Nuffield College, Oxford. I thank my hosts for their hospitality. D. Dimitrov and F. Maniquet have provided valuable comments on an earlier draft. I also thank the audience of a seminar at the U. of Montreal. Finally, the comments of three anonymous referees and the Associate Editor have been very helpful.     

世博会国家展馆生态环保材料应用研究

本文通过对历届世博会国家展馆设计中生态环保材料应用的研究,总结了生态环保材料应用的若干特性,强调了国家展馆在设计与实施过程中应实现国家特性和生态环保材料应用相结合,提倡建筑师充分运用各种生态环保材料,使设计获得独特的效果,同时为人类的可持续发展作出贡献。     

Limit theory for panel data models with cross sectional dependence and sequential exogeneity

The paper derives a general Central Limit Theorem (CLT) and asymptotic distributions for sample moments related to panel data models with large n$n$. The results allow for the data to be cross sectionally dependent, while at the same time allowing the regressors to be only sequentially rather than strictly exogenous. The setup is sufficiently general to accommodate situations where cross sectional dependence stems from spatial interactions and/or from the presence of common factors. The latter leads to the need for random norming. The limit theorem for sample moments is derived by showing that the moment conditions can be recast such that a martingale difference array central limit theorem can be applied. We prove such a central limit theorem by first extending results for stable convergence in Hall and Heyde (1980) to non-nested martingale arrays relevant for our applications. We illustrate our result by establishing a generalized estimation theory for GMM estimators of a fixed effect panel model without imposing i.i.d. or strict exogeneity conditions. We also discuss a class of Maximum Likelihood (ML) estimators that can be analyzed using our CLT.