THE EFFECTS OF CORRELATION AMONG OBSERVATIONS ON THE ACCURACY OF APPROXIMATING THE DISTRIBUTION OF SAMPLE MEAN BY ITS ASYMPTOTIC DISTRIBUTION1

In this paper, we investigate the effects of correlation among observations on the accuracy of approximating the distribution of sample mean by its asymptotic distribution. The accuracy is investigated by the Berry-Esseen bound (BEB), which gives an upper bound on the error of approximation of the distribution function of the sample mean from its asymptotic distribution for independent observations. For a given sample size (n₀) the BEB is obtained when the observations are independent. Let this be BEB. We then find the sample size (n_*) required to have BEB below BEB₀, when the observations are dependent. Comparison of n_* with n₀ reveals the effects of correlation among observations on the accuracy of the asymptotic distribution as an approximation. It is shown that the effects of correlation among observations are not appreciable if the correlation is moderate to small but it can be severe for extreme correlations.     

关于捕获再捕获抽样的置信区间

捕获再捕获抽样是一种应用广泛的抽样方法。运用随机模拟,研究捕获再捕获抽样的三种估计量的均值、方差、偏度、峰度、利用近似正态分布构造的置信区间的统计性质。改进了估计量的样本方差计算公式,使得利用近似正态分布构造的置信区间更优。     

沿海发达地区新型城镇化路径研究——以浙江省中心镇培育小城市为例

小城市是在中心镇的基础上,按照城市的理念、形态和标准进行培育建设,集聚度和功能性高于中心镇的城市形态。把中心镇培育成为小城市是实施新型城镇化战略的重大创新。浙江省在全国较早进行小城市培育试点,在推进农民集中式居住、强化素保障、提升公共服务能力等方面对小城市培育进行了探索创新,但也存在一些突出矛盾和问题。因此从思想观念、规划布局、城市经济、体制改革等方面入手,促进人口集中、产业集聚、功能集成和素集约,加快中心镇转型升级,实现由镇向城的真正跨越。     

Normalization in Econometrics

The issue of normalization arises whenever two different values for a vector of unknown parameters imply the identical economic model. A normalization implies not just a rule for selecting which among equivalent points to call the maximum likelihood estimate (MLE), but also governs the topography of the set of points that go into a small-sample confidence interval associated with that MLE. A poor normalization can lead to multimodal distributions, disjoint confidence intervals, and very misleading characterizations of the true statistical uncertainty. This paper introduces an identification principle as a framework upon which a normalization should be imposed, according to which the boundaries of the allowable parameter space should correspond to loci along which the model is locally unidentified. We illustrate these issues with examples taken from mixture models, structural vector autoregressions, and cointegration models.     

Use of the scale-up methods in injury prevention research: An empirical assessment to the case of choking in children

The scale-up method estimates the size of hard to count subpopulations. This method is based on the idea that the proportion of subjects in a subpopulation E known to each member of the general population T is the same as the proportion of members of E belonging to general population T.     

新型小锯片烧结炉的研制

用新材料制作的金刚石小锯片烧结炉具有传热快、温差小、寿命长、节能省电等特点,是小锯片烧结工艺研究和小批量生产的理想设备。     

中小企业组织道德氛围及其对组织绩效的影响——基于浙江等省市的调查与分析

组织道德氛围是近年西方企业伦理研究领域的热点之一,但一直以来分类为导向的研究思路已受到诸多质疑。本研究在深度访谈及对来自不同省市、不同行业的84家中小企业的785名各级员工进行问卷调查的基础上,从组织道德决策的角度构建了中小企业组织道德氛围以及组织绩效的结构模型,并分析了组织道德氛围对组织绩效的影响。结果表明,中小企业组织道德氛围包含集体道德意识、关注他人、关注自我、集体道德动机、集体道德性格5个维度;组织绩效包含一般满意感、道德满意感、总体绩效3个维度;组织道德氛围各维度对组织绩效具有直接、显著的预测作用,其中对道德满意感的预测效果最好。     

基于语料库的山镇风俗文化英译研究——以戴乃迭《芙蓉镇》英译本为例

基于《芙蓉镇》汉英平行语料库,提取与山镇风俗文化相关的圩场、吊脚楼和民歌等意象,考察山镇风俗文化英译后的变化和原因。研究发现,原文中具有浓郁地域特征和时代特色的山镇风俗文化在译文中仅有部分保留,地方风俗的画面感和现实感被弱化,而由山镇风俗变化所折射出的时代特色和思想变迁也有所淡化。究其原因,主要是译者在翻译过程中考虑到目的语读者的文化背景、译者的文化身份以及中国文化走出去的需要。     

创新制胜——中小企业的竞争战略

中小企业是各国的经济主体,在经济全球化的今天,中小企业的发展既面临机遇,也面临诸多挑战。发展壮大是广大中小企业的共同目标。单纯模仿对中小企业来说是条死胡同,而模仿创新非常适合中小企业的特点和需要,是其发展壮大的锐器。     

中国"小组"政治组织模式分析

小组,是广泛存在于中国各级党政机关中以议事协调机构和临时机构名义存在的一种特殊组织模式。基于制度层面的静态分析,影响小组产生并长期存在的因素,主要包括政府横向间机构设置的小部门结构、政府纵向间职责配置的职责同构格局等结构性因素,单任务—泛职能的功能性因素,分管型副职模式的制度性因素;其类型包括:根据存在时限可划分为常设型、阶段型、短期型,根据权属关系可划分为职责同构型、权责自属型。基于技术层面的动态分析,小组的中轴依附的组织结构特点,虚实结合的存在方式,倍量增减的运行过程,这三个要素共同构筑了小组独具特色的运转系统。