MODELING LIQUIDITY EFFECTS IN DISCRETE TIME

We study optimal portfolio choices for an agent with the aim of maximizing utility from terminal wealth within a market with liquidity costs. Under some mild conditions, we show the existence of optimal portfolios and that the marginal utility of the optimal terminal wealth serves as a change of measure to turn the marginal price process of the optimal strategy into a martingale. Finally, we illustrate our results numerically in a Cox–Ross–Rubinstein binomial model with liquidity costs and find the reservation ask prices for simple European put options.     

发展传播学视野中的媒介理论变迁

发展传播理论是20世纪下半叶以来围绕传播与社会发展问题兴起的理论范式。由于全球大众传播领域的迅猛发展以及全球政治经济结构的变化,发展传播理论经历了自身理论范式的转换,并面对全球化的新发展视野。重新审视20世纪50年代以来发展传播学视野中大众媒介的角色与功能,在构建和谐社会、全面建设小康社会的国内环境以及全球化的语境中具有重要意义。     

国外关于边境效应引力模型研究现状

自20世纪60年代以来,引力模型被广泛地应用于研究国际贸易中的双边贸易流量。在引力模型不断发展和完善的基础上,众多学者开始从不同角度研究基于引力模型的边境效应问题。本文试图将国外繁多的研究进行总结和概述,以推动国内对于边境效应引力模型的理论和实证研究。     

中国总量性非自愿失业模型生成机制研究——基于凯恩斯就业理论的视角

中国失业问题主要不是结构问题，而是总量问题。运用凯恩斯就业理论中的周期性总量性失业模型。对长期总量性非自愿失业的生成机制的研究发现，应从控制人口增长、降低劳动参与率、缩短劳动时间及实行灵活的就业制度等方面扩张潜在就业规模，从而有效治理失业问题。促进社会的和谐发展。     

依附理论视野下的留守儿童边缘化危机与健康成长研究

依附理论是分析非西方欠发达国家及其边缘化危机的一种范式。运用依附理论框架对留守儿童边缘化危机进行分析发现：社会转型是留守儿童边缘化危机浮现的宏观背景，体制分割是留守儿童边缘化危机加剧的中观设置，社会化偏差是留守儿童边缘化危机突显的微观环境。通过转换发展模式，破解二元对立社会结构；创新社会设置，消解二元分割教育体制；优化社会化环境，矫正留守儿童社会化偏差等措施，才能化解留守儿童边缘化危机。     

Changes in Factor Betas and Risk Premiums Over Varying Market Conditions

We show risk exposures and premiums associated with the Chen, Roll, and Ross (1986) risk factors change over time and depend on stock market and business cycle condition. Findings also indicate that factor risk premiums change sign between January and non-January, especially during bull markets. These findings serve as a caveat for portfolio managers who allocate assets to match desired exposures to key macroeconomic risk factors.     

The processes of defining corporate responsibility: a study of Swedish garment retailers' responsibility

Despite extensive research on corporate responsibility, little research exists on how the inter‐organizational processes of defining corporate responsibility develop. In this paper, we present a framework based on actor‐network theory (ANT) for analysing these processes. The developed framework is illustrated in a study of the redefinition of Swedish garment retailers' responsibilities for workers' rights at suppliers' factories between 1996 and 2004. We show that definition processes can be characterized as battles for the right to interpretation, and that traditionally non‐dominant actors can, at least temporarily, win these battles and dictate the development of the processes for defining corporate responsibility. We also show that definition processes can take an exclusionary form prohibiting certain actors from participating. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.     

The judicious use and management of humor in the workplace

Everybody loves humor. In the workplace, it can provide such benefits as stress relief, team unification, employee motivation, idea generation, and frustration diffusion through venting. Despite these positives, it should be stressed that humor in this context has downsides, as well. For example, humor can distract us from the job at hand, hurt our credibility, or cause offense in increasingly diverse work settings. In the midst of this complicated situation stand managers, who occupy a position of responsibility for both the good and bad effects of humor in the workplace. It is the intention of this article to use existing humor theory and a simple model to generate a more analytical understanding of humorous interaction. Suggestions are then offered as to how to use humor and manage the use of humor in such a way as to maximize its benefits, while minimizing its dangers.     

Price competition during and after promotions

We provide a framework for setting regular prices and using promotional discounts in a duopoly where long‐term promotional effects are present and the firms' pricing and promotional strategies are common knowledge (e.g., as in online markets). We show that at equilibrium, the two firms may not promote and instead adopt an Everyday Low Price (EDLP) strategy. Consumers' tendency to stockpile promoted products, the level of brand loyalty and product differentiation, and the possibility of a postpromotional sales increase critically influence regular prices, price discount rates, and profits. Under some conditions consumer stockpiling intensifies promotional competition and reduces firms' profits while the possibility of attracting new consumers reduces the need to heavily promote and ensures better profits. Managerial implications are discussed. Copyright © 2007 ASAC. Published by John Wiley & Sons, Ltd.