我国制造业集聚变迁与全要素生产率增长研究

本文选取我国29个省市区和17个制造行业1990～2009年的面板数据,对相对专业化与相对多样化集聚度进行了计算及变迁分析,利用Malmquist指数测算了全要素生产率的增长,并分析了产业集聚变迁对全要素生产率的影响。结果表明:我国东部地区呈现多样化与专业化集聚均衡发展的特征,而中西部地区则具有相对较高的专业化集聚水平,呈现产业结构单一化与非均衡化;东部地区全要素生产率增长较快,中西部地区相对滞后;相对专业化与多样化集聚对东部、中部与西部地区的影响存在地区差异。基于此,本文提出了加快产业结构调整、实施均衡的区域发展政策和提高经济组织制度绩效的政策建议。     

网络与集群:温州企业家群体形成的机制分析

同历史上地域性企业家集群(商帮)类似,温州呈现了一种独有的企业家集群的现象.本文首先给出了温州企业家集群的整体描述,然后例举了三种典型的温州企业家集群.通过企业家集群和社会网络研究的综述,以及对温州企业家集群形成的历程分析,提出了五个基于社会网络理论的基本假设,认为温州企业家集群出现的主要原因在于“瓯文化”,“瓯文化”是温州企业家精神和企业家“干中学”才能形成的渊源.     

Back to basics: explaining sample size in outcome trials,are statisticians doing a thorough job?

Time to event outcome trials in clinical research are typically large, expensive and high‐profile affairs. Such trials are commonplace in oncology and cardiovascular therapeutic areas but are also seen in other areas such as respiratory in indications like chronic obstructive pulmonary disease. Their progress is closely monitored and results are often eagerly awaited. Once available, the top line result is often big news, at least within the therapeutic area in which it was conducted, and the data are subsequently fully scrutinized in a series of high‐profile publications. In such circumstances, the statistician has a vital role to play in the design, conduct, analysis and reporting of the trial. In particular, in drug development it is incumbent on the statistician to ensure at the outset that the sizing of the trial is fully appreciated by their medical, and other non‐statistical, drug development team colleagues and that the risk of delivering a statistically significant but clinically unpersuasive result is minimized. The statistician also has a key role in advising the team when, early in the life of an outcomes trial, a lower than anticipated event rate appears to be emerging. This paper highlights some of the important features relating to outcome trial sample sizing and makes a number of simple recommendations aimed at ensuring a better, common understanding of the interplay between sample size and power and the final result required to provide a statistically positive and clinically persuasive outcome. Copyright © 2009 John Wiley & Sons, Ltd.     

Comparing mean ranks for repeated measures data

Rank tests are considered that compare t treatments in repeated measures designs. A statistic is given that contains as special cases several that have been proposed for this problem, including one that corresponds to the randomized block ANOVA statistic applied to the rank transformed data. Another statistic is proposed, having a null distribution holding under more general conditions, that is the rank transform of the Hotelling statistic for repeated measures. A statistic of this type is also given for data that are ordered categorical rather than fully rankedo Unlike the Friedman statistic, the statistics discussed in this article utilize a single ranking of the entire sample. Power calculations for an underlying normal distribution indicate that the rank transformed ANOVA test can be substantially more powerful than the Friedman test.     

R–estimation of normed bivariate density functions

Normed bivariate density funtions were introduced by HOEFFDING (1940/41). In the present paper estimators for normed bivariate ranks and on a FOURIER series expansion in LEGENDRE polynomials. The estimation of normed bivarate density functions under positive dependence is also described     

A Comparison of Hierarchical Methods for Clustering Functional Data

Functional data analysis (FDA)—the analysis of data that can be considered a set of observed continuous functions—is an increasingly common class of statistical analysis. One of the most widely used FDA methods is the cluster analysis of functional data; however, little work has been done to compare the performance of clustering methods on functional data. In this article, a simulation study compares the performance of four major hierarchical methods for clustering functional data. The simulated data varied in three ways: the nature of the signal functions (periodic, non periodic, or mixed), the amount of noise added to the signal functions, and the pattern of the true cluster sizes. The Rand index was used to compare the performance of each clustering method. As a secondary goal, clustering methods were also compared when the number of clusters has been misspecified. To illustrate the results, a real set of functional data was clustered where the true clustering structure is believed to be known. Comparing the clustering methods for the real data set confirmed the findings of the simulation. This study yields concrete suggestions to future researchers to determine the best method for clustering their functional data.     

The Effects of a Computer Network on Pediatric Pain and Anxiety

SUMMARY

The objective of this study was to test the impact of an enhanced version of STARBRIGHT World (SBW2)-a private computer network for hospitalized children. The impact of SBW2 was assessed with a series of 44 replicated single system designs. Utilizing an ecological momentary assessment approach, self-reports were obtained regarding children's perceptions of their pain intensity, pain aversive-ness and anxiety. The results from the single system designs were aggregated using meta-analysis. Children experienced significantly less pain intensity, pain aversiveness, and anxiety in the SBW2 condition. These findings provide evidence regarding the effectiveness of SBW2 and demonstrate the utility of employing meta-analysis with single system designs.     

Web-Enhanced Preservice Training for Prospective Resource Parents: A Randomized Trial of Effectiveness and User Satisfaction

ABSTRACT

Traditionally, prospective resource parents must attend all preservice training in person. Although live sessions are necessary for screening applicants, instructional portions of training could be enhanced by Web-based sessions. This pilot study compares the effectiveness of online and classroom versions of one session from a widely used preservice training program. Ninety-two individuals enrolled in the program in two states were randomly assigned to a treatment group that viewed an online version of the class on child abuse and neglect or to a comparison group that took the same class in person. Written questionnaires were completed before and after the class. Significant group differences on knowledge of child maltreatment and empathy toward birth parents plus high user satisfaction were hypothesized. Analysis of covariance results showed the online training was more effective than the live training at increasing knowledge. Multivariate analysis of covariance findings on empathy were not significant but trended toward greater empathy for the online group. Feedback indicated high satisfaction with the online course. The finding that online instruction is more effective than live instruction has positive implications for practice, because Web-based training offers advantages like standardizing instruction, cutting agency and trainee costs, and providing greater flexibility.     

我国产业集群促进实践中的问题研究——基于欧洲各国的集群政策经验

将我国地方政府与欧洲各国地方政府集群促进与政策实践比较之后发现,政府在集群促进中的角色设定上,在集群运行机理认识上,在政策工具运用上,在集群识别与支持对象选择上,在政府集群促进行动方式上,在政府对于集群资助方式上均存在着较大差异。分析讨论表明,这些差异主要不是因为国情不同,或体制不同造成的,而是因为地方政府对市场经济不适应造成的,进而揭示并讨论了我国一些地方政府集群促进政策实践中的问题。     

集群剩余与企业集群内部协调机制

企业集群内部协调既不同于市场上价格机制的无形之手,又不同于企业内部行政命令的有形之手。本文分析指出,集群内部协调的目标在于追求集群剩余,并根据企业行为的规律性对集群剩余进行了分析;介绍集群内部的各种协调机制,在此基础上,分析协调机制与集群剩余实现之间的关联。