Local dependence estimation using semiparametric archimedean copulas

The authors define a new semiparametric Archimedean copula family which has a flexible dependence structure. The generator of the family is a local interpolation of existing generators. It has locally‐defined dependence parameters. The authors present a penalized constrained least‐squares method to estimate and smooth these parameters. They illustrate the flexibility of their dependence model in a bi‐variate survival example.     

克隆技术对人类社会的影响

本文分析了克隆技术对社会发展的积极作用和消极影响 ,分析了“Clone”技术的必然发展趋势 ,预言了“Clone”技术对人类社会的深层影响及对策 ,提示人类应用该项技术时要趋利避害     

知识型企业结构、特征及报酬递增效应分析

在市场经济条件下,知识已经成为企业竞争力的源泉.知识经济、知识管理、知识型企业等思想被越来越多的人所接受.和传统企业相比,知识型企业的结构及特征有它特定的一面.文章在分析知识型企业内外部结构的基础上,对知识型企业的特征进行了分析,进而探讨了由其特征所决定的知识型企业生产函数及报酬递增效应.     

社区卫生服务中心与医院手术费用的比较研究

目的:比较社区卫生服务中心及各级医院常见手术费用;社区卫生服务中心手术是否便捷、低耗,有无保留的必要。方法:调研南京市社区卫生服务中心及各级医院常见手术的单病种费用,社区卫生服务中心与各级医院的费用做统计分析比较。结果:社区卫生服务中心单病种手术平均住院费用明显低于与各级医院。结论:从经济学的角度分析,各级医院手术费用差别很大,在规范和安全的前提下,社区卫生服务中心保留基本的手术功能是符合社区居民需求和社区卫生服务自身发展需要的。     

教师话语标记语与课堂语境

在话语交际中,说话人为了实现交际目的,不仅要传递基本信息,还要用恰当的语言手段和语言成分来传达语用信息,构建语篇语境。话语标记语是说话人明示话语意图的手段,是听话人推导话语意义的标识。课堂语境具有很强的可构建性,教师话语标记语对课堂语境的构建起着重要的作用。     

Estimating rating transition probabilites with missing data

In this article we provide a rigorous treatment of one of the central statistical issues of credit risk management. GivenK-1 rating categories, the rating of a corporate bond over a certain horizon may either stay the same or change to one of the remainingK-2 categories; in addition, it is usually the case that the rating of some bonds is withdrawn during the time interval considered in the analysis. When estimating transition probabilities, we have thus to consider aK-th category, called withdrawal, which contains (partially) missing data. We show how maximum likelihood estimation can be performed in this setup; whereas in discrete time our solution gives rigorous support to a solution often used in applications, in continuous time the maximum likelihood estimator of the transition matrix computed by means of the EM algorithm represents a significant improvement over existing methods.     

On pooling data summaries in the absence of interactions “response-by-study”

The standard hypothesis testing procedure in meta-analysis (or multi-center clinical trials) in the absence of treatment-by-center interaction relies on approximating the null distribution of the standard test statistic by a standard normal distribution. For relatively small sample sizes, the standard procedure has been shown by various authors to have poor control of the type I error probability, leading to too many liberal decisions. In this article, two test procedures are proposed, which rely on thet—distribution as the reference distribution. A simulation study indicates that the proposed procedures attain significance levels closer to the nominal level compared with the standard procedure.     

基于Windows CE移动商务的Internet连接技术

文章主要介绍了WinInet函数 ,以及通过该函数实现与Internet的连接技术     

具有生存性的WDM网络性能分析

研究了在动态业务量时,可调谐光收发器和波长变换器对生存性WDM网络性能的影响。通过在NSFNET、CERNET、MESH-TORUS网络中的仿真,又从网络阻塞率方面研究了两者对WDM网络性能的影响。研究结果表明,在业务量为动态的生存性WDM网络中,可调谐光收发器和波长变换器对网络的性能都有显著的提高,但波长变换器对网络性能的改善要大于可调谐光收发器。     

两性言语交际中的语用功能和文化属性探析

本文从话语量、话题控制和礼貌用语三个方面论述了两性言语交际过程中的用语特征,并从语用功能和文化属性二个层面对其特征进行了分析。最后指出:随着社会的发展和观念的更新,两性用语在言语交际过程中趋向于相互补充和混合,且更有助于交际。