Overall Successful Aging: Its Factorial Structure and Predictive Factors

As the concept of successful ageing (SA) tends to take different meanings among researchers, there is a lack of consensus on how to measure SA. In order to address this gap, the present study aims to explore the factor structure of SA involving SA indicators presented in the literature. Using Americans' Changing Lives study (ACL), a second-order confirmatory factor analysis on factors constituting an overall SA measure and a SEM regression model to examine the predictive factors of the overall SA measure were estimated. A second-order confirmatory factor model including three latent constructs of SA – Physical Domain (diseases, functional health, and physical activity), Mental Domain (depression, self-efficacy, and cognitive impairment), and Social Domain (formal social integration, informal social integration, and social support) – fits the data properly. The findings of a SEM regression model replicates the findings of previous SA research, suggesting the overall SA latent construct is a valid measure for SA.     

机会约束下的含有资本结构因子和交易成本的均值-VaR投资组合模型

本文在均值-方差模型和机会约束模型的基础上,提出了在允许卖空时的一类机会约束下含有资本结构因子和交易成本的均值-VaR证券投资组合模型,以期望收益率与置信水平为导向,在假设收益率服从正态分布的条件下,建立了其数学模型,并讨论了最优解的存在性和唯一性,以及最优解的解析表达式。     

上市公司股权变更与公司产出效率的研究

该文以1999～2003年间沪、深两市发生的699起股权转让超过5％的并购事件为有效样本事件,利用生产函数计算出公司并购前后的全要素生产率,并分析了不同并购活动对产出效率的影响。实证研究表明,整体上看,公司股权转让后产出效率得到提高,但对长期产出效率改善缺乏持续性;混合并购使股权转让公司的效率提高,而横向和纵向并购却降低了目标公司的效率。另外,研究还表明,在不同的所有权结构下,公司的产出效率并不存在显著性的差异。     

Customer Behavior Modeling in Revenue Management and Auctions: A Review and New Research Opportunities

Customer behavior modeling has been gaining increasing attention in the operations management community. In this paper we review current models of customer behavior in the revenue management and auction literatures and suggest several future research directions.     

供应链物流运作能力计划模型与分析

考察了某种产品供应链系统的一次性物流运作过程,建立了这个系统的物流能力动态规划模型。针对供应链中物流运作能力的流通量指标进行了较为深入的理论分析,探讨了使得系统成本最小化的最优物流能力及系统各阶段需配置的流通量。最优物流能力策略体现为两个关键量,即下界和上界。如果可得输入量小于下界则选择不开展物流;如果可得输入超出了下界,物流能力可以足够大但不超过上界。运用数学归纳法对优化结果进行了证明,并结合算例检验了模型的效果。     

A Supply Chain with a Service Requirement for Each Market Signal

We study a single‐period two‐stage service‐constrained supply chain with an information update. The buyer has two procurement opportunities with the second one after observing a market signal, which updates the demand forecast. He also commits to a service level after observing the market signal. We derive his optimal ordering decisions and show that the critical market signal, the optimal first‐stage order quantity, and the optimal expected profit are monotone with respect to the target service level. We also discuss the impact of the forecast quality on the optimal decisions. We show that the optimal first‐stage order quantity may not be monotone with respect to information accuracy, as is in the case without the service constraint. In addition, we extend our analysis to the situation when an order cancellation is allowed upon the observation of the market signal. We also compare the results obtained for the problems with and without an order cancelation. Finally, we discuss the supply chain coordination issue and find that a buyback contract can also coordinate the supply chain in the presence of the service constraint.     

西部信息产业的比较优势

本文是西部信息产业科技发展战略项目的研究结果之一.文章首先提出了界定西部信息产业比较优势的理论原则,在此基础上,研究了西部重点城市在IT领域的比较优势,并对其变化趋势做了动态分析.     

论非理性因素对社会进步和人的全面发展的影响

人的非理性因素诸如欲望、兴趣、激情、信念、意志等对社会进步和人的全面发展既有积极的作用又有负面效应.要充分发挥非理性因素的积极作用,抑制、弱化其消极作用,我们必须在社会实践基础上实现理性和非理性的协调统一,在理性的支配和指导下,发挥非理性因素的积极作用;必须使人的非理性因素顺应社会客观规律,推动社会的发展;必须加强人的非理性因素的教育和培养,塑造现代理想的人格,促进人的全面发展;要营造一个良好社会环境,加强社会的综合治理,使非理性因素的积极作用得到充分发挥,推动和促进社会的进步和人的全面发展.     

论诗意象的总体特征

诗的意象不同于一般的艺术形象,因为它是不确定性和确定性的统一;诗的意象不同于其他的文学形象(如小说形象、戏剧形象等),因为它在不确定性和确定性的统一中,以不确定性为主.     

论影响人力资源决策的若干因素

在经济全球化的今天,人力资源管理的作用日益突显,而人力资源决策则是人力资源管理的基础。纵观影响人力资源决策的因素,应主要包括决策者本身、社会环境、信息系统、决策方法方式等诸多方面曰