公司治理与会计盈余分红相关性的实证研究

股利政策是平衡上市公司税后收益和留存收益之间关系、进行投资者管理的重要手段。以中国上市A股2009年财务和公司治理数据为研究样本实证研究公司治理与会计盈余分红的关系,研究结果表明,在控制公司具体特征因素之后,公司会计盈余分红与控股股东比例、董事会规模、监事会规模呈正相关,与流通股比例呈负相关。因此,平衡上市公司税后收益和留存收益之间关系,实施投资者管理的重要股利政策包括优化股权结构,改革股东大会表决制度;细化强制分红、提高分红信息的透明度。     

长尾时代的中小企业柔性战略

战略环境变化要求企业战略具备柔性内涵。中小企业柔性战略的提出是基于其独特的企业属性;长尾时代中小企业柔性战略实现的关键在于其应变意识和应变能力的培育,因此进一步完善企业文化建设、提高信息获取能力和资源运用能力是实现中小企业柔性战略的重要途径。     

The effect of objective job demands on registered sickness absence spells; do personal,social and job-related resources act as moderators?

Abstract

This study applied Karaseks demand-control model, using sense of coherence (SOC), social support and job control as moderators of effects of job demands on ensuing sickness absence spells in a 3-year follow-up of 856 municipal employees. Among men the results supported the active learning hypothesis. Passive jobs predicted a high number of sickness absence spells and active jobs predicted a low number of spells. for short spells (1-3 days), the demand-control interaction, however, depended on SOC. In active jobs SOC was negatively associated with sickness absence spells; in passive jobs no such association was found. For long spells (3 days), the demand-control interaction depended on occupational level; active jobs were predictive of low absence spells among blue collar men. Among women, the results supported the strain hypothesis. The demand-control interaction, however, depended on household size. In small households, high-strain jobs predicted a high number of spells, while no increase in spells was found in active versus low-strain jobs. In larger households, the number of spells correlated positively with increasing demands even when control was good. The demand-control interaction, however, depended on SOC and spouse support. With strong SOC or spouse support, absence spells in active jobs remained on a relatively low level, otherwise active jobs led to a high number of spells. This suggests that SOC and spouse support may act as protective factors against female role conflicts associated with active jobs     

国际储备理论与中国国际储备的适度规模

在理论与实证分析的基础上,对中国国际储备的规模问题作结构分析,不仅要关注中国国际储备适度规模的数量区间,更要加强对国际储备的结构安排与价值管理。当前迫切需要我们考虑的是如何管理好和利用好如此高额的国际储备。通过中国国际储备规模的实证考察,提出中国国际储备适度规模及其对策。     

Sample‐size calculations for multi‐group comparison in population pharmacokinetic experiments

This paper describes an approach for calculating sample size for population pharmacokinetic experiments that involve hypothesis testing based on multi‐group comparison detecting the difference in parameters between groups under mixed‐effects modelling. This approach extends what has been described for generalized linear models and nonlinear population pharmacokinetic models that involve only binary covariates to more complex nonlinear population pharmacokinetic models. The structural nonlinear model is linearized around the random effects to obtain the marginal model and the hypothesis testing involving model parameters is based on Wald's test. This approach provides an efficient and fast method for calculating sample size for hypothesis testing in population pharmacokinetic models. The approach can also handle different design problems such as unequal allocation of subjects to groups and unbalanced sampling times between and within groups. The results obtained following application to a one compartment intravenous bolus dose model that involved three different hypotheses under different scenarios showed good agreement between the power obtained from NONMEM simulations and nominal power. Copyright © 2009 John Wiley & Sons, Ltd.     

Teachers,Schools, and Academic Achievement

This paper disentangles the impact of schools and teachers in influencing achievement with special attention given to the potential problems of omitted or mismeasured variables and of student and school selection. Unique matched panel data from the UTD Texas Schools Project permit the identification of teacher quality based on student performance along with the impact of specific, measured components of teachers and schools. Semiparametric lower bound estimates of the variance in teacher quality based entirely on within‐school heterogeneity indicate that teachers have powerful effects on reading and mathematics achievement, though little of the variation in teacher quality is explained by observable characteristics such as education or experience. The results suggest that the effects of a costly ten student reduction in class size are smaller than the benefit of moving one standard deviation up the teacher quality distribution, highlighting the importance of teacher effectiveness in the determination of school quality.     

北京市劳动年龄人口规模变动及其影响因素分析

本项研究以劳动年龄人口变动为出发点,以出生人口规模变动的影响为落脚点,研究影响北京劳动年龄人口变动的主要因素,为今后合理开发利用和优化北京劳动力资源、完善人口迁移流动政策、完善劳动就业政策、完善生育政策以及探讨北京今后劳动力资源面临的主要问题等研究奠定基础。     

经济、管理类专业《统计学》课程建设的几个基本问题

内容提要：本人认为,目前在我国经济、管理类专业《统计学》课程建设中尚有一些基本理论问题需要讨论清楚。例如,怎样理解“统计学是一门数据科学”这一命题,以及课程改革后的《统计学》与改革前的《社会经济统计学原理》究竟有什么本质上的区别;《统计学》课程中用于对重复随机试验进行统计推断的样本和抽样调查中的样本有什么区别和联系;应用社会经济调查数据进行统计分析较之应用实验数据进行统计分析有什么特殊性的问题需要解决,等等。文章找出了这些问题的若干误区并阐述了作者的个人见解。     

A note on the queue with a random set-up time under a restricted admissibility policy with a Bernoulli vacation schedule

This paper deals with the queue size distribution of an M^x/G/1 queue with a random set-up time and with a Bernoulli vacation schedule under a restricted admissibility policy. This generalizes the model studied by Madan and Choudhury [Sankhyá 66 (2004) 175–193].     

集聚效应、集聚效率与城市规模分布变化

摘　　要:本文从城市集聚效应的视角,分析我国城市规模分布的结构性变化的机制,在此基础上构建了包含集聚效应的城市总量生产函数的计量经济学模型,然后应用OLS方法估算我国不同规模等级城市的平均集聚效应指数和平均集聚效率指数．并对比分析其对城市规模分布变化的影响。本文的实证结果表明,平均集聚效率指数的高低与城市规模分布比重的增减相一致。