Advertising, Its Determinants, and Market Structure

This study derives a formal model of firm advertising behavior and applies it to the industry level to figure out the relationship between advertising and market structure. The firm advertising model shows that both consumer preference andfirm-specific advertising competence jointly determineprofit-maximizing advertising intensity. At the industry level, advertising intensity is represented multiplicatively by consumer preference and a measure of market structure, which reflects the joint distribution of the levels of advertising competence and market shares among firms. The new market structure measure suggests that those single-dimensional measures of market structure such as seller concentration and the Herfindahl index are inadequate in explaining interindustry differences in advertising intensity, and that the long-debated advertising-concentration relationship differs depending primarily on the appropriability of advertising. An empirical analysis of 426 five-digit Korean manufacturing industries shows that an inverted U-shaped relationship between the Herfindahl index and industry advertising intensity is observed for consumer goods industries but a lazy J-shaped relationship for producer goods industries.     

The equilibrium set of two-player games with complementarities is a sublattice

Summary. I prove that the equilibrium set in a two-player game with complementarities, and totally ordered strategy spaces, is a sublattice of the joint strategy space. Received: May 31, 2001; revised version: October 4, 2002     

积分第一中值定理的证明与推广

本文根据积分上限函数的性质利用微分中值定理证明了积分第一中值定理,用改进的介值定理证明了ξ∈(a,b),并推广了积分第一中值定理。     

美国联邦宪法基本人权保障的发展路径

从中世纪英格兰开始,再延续至北美殖民时代,对普通法体系建立和权力法案的形成沿革进行详细的阐述,以美国独立宣言、宪法前言及人权典章所构筑的宪法优先原则,透过美国联邦最高法院的审查,形成限制国家权力的框架,具体落实宪法规范之最高性及权力分立,借此保障基本人权。     

Liquidity risk and arbitrage pricing theory

Classical theories of financial markets assume an infinitely liquid market and that all traders act as price takers. This theory is a good approximation for highly liquid stocks, although even there it does not apply well for large traders or for modelling transaction costs. We extend the classical approach by formulating a new model that takes into account illiquidities. Our approach hypothesizes a stochastic supply curve for a securitys price as a function of trade size. This leads to a new definition of a self-financing trading strategy, additional restrictions on hedging strategies, and some interesting mathematical issues.Received: 1 November 2003, Mathematics Subject Classification: 60G44, 60H05, 90A09JEL Classification: G11, G12, G13Umut Çetin: This work was performed while Dr. Çetin was at the Center for Applied Mathematics, Cornell UniversityPhilip Protter: Supported in part by NSF grant DMS-0202958 and NSA grant MDA-904-03-1-0092 The authors wish to thank M. Warachka and Kiseop Lee for helpful comments, as well as the anonymous referee and Associate Editor for numerous helpful suggestions, which have made this a much improved paper.     

一类泛函脉冲微分方程周期正解的存在性

利用Krasnoselskii不动点定理,讨论一类带参数的泛函脉冲微分方程多个周期正解存在的充分条件,在f(x)和I_k(x) 均为非超线性和非次线性的条件下,得到该类微分方程多个周期正解存在的一些新结果。     

基于耦合模型的中国科技成果转化的社会运行系统的理论研究

本文认为,在科技成果转化过程中,政府、大学、科研院所、中介与企业构成了转化作用的基本主体,这些独立主体是一种耦合作用的单元,可以用耦元进行描述,即这些耦元之间的关系决定了科技成果转化的效率。事实上,这些耦元之间的相互作用存在着复杂性,只有在合适的条件下才可以成功地进行科技成果转化。因此,本文使用生物耦合概念以及原理分析影响科技成果转化的各种核心因素之间的关系,探索影响因素之间的恒定关系,试图找到影响科技成果转化的各种因素相互作用的一般规律,建立合理的科技成果转化管理体系。     

An alternative proof of the nonemptiness of the private core

Summary. We focus on the private core [19] of an economy with a finite number of agents with differential information, a continuum of states and an infinite number of commodities. We state a nonemptiness result for the private core and provide a proof based on a fixed-point argument. Received: October 4, 1999; revised version: June 7, 2000     

关于中国现代经济理论的基本问题

中国现代经济理论是辛亥革命以来关于振兴中华、富民强国的一系列经济观点、思路、理论及学说的总和,是在中国国情与社会发展的基础上学习并借鉴西方经济理论与发展经验,以追求并实现现代化为核心内容的具有中国风格和中国特色的经济理论体系。深刻理解与把握中国现代经济理论的涵义、性质、任务、分期、构成以及研究的基本问题,对于进一步完善中国现代经济理论的学科建设和深刻理解中国特色社会主义的理论与实践至关重要。     

Factor substitution and factor intensities in models with more factors than goods

This paper considers the commodity prices–factor prices relation in models with more factors than consumption goods. Under some simple factor substitutability assumptions, many results in the   n  ×  n   cases have counterparts in the   l  ×  n   cases. The proportional price changes of the "middle factors" will be trapped between those of the "extreme factors". A weak and a strong Stolper–Samuelson theorem can also be proven. If the numbers of goods and perfectly complementary factors are equal and the production functions have the nested constant elasticity of substitution form, two of the complementary factors would have the most extreme relative price changes, regardless of the factor intensities.