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1.
传统的国际关系理论,无论是现实主义、自由主义、建构主义还是科学行为主义理论,都是把主权国家抽象成一个统一的国际关系行为体。这一行为主体有一致的利益,也自然要有一致的对外政策目标和手段。在20世纪,尤其是在两次世界大战和冷战期间,这一概念抽象是非常准确的。但冷战结束以后,尤其是进入21世纪以后,这一概念抽象逐渐与国际关系的现实相违背。一方面,国家综合实力并不能直接转化为具体领域的竞争优势;另一方面,很多国家,包括超级大国在内,其对外政策的主要阻力可能不是所谓的竞争对手,而是其国内不同的利益集团。这导致传统的国际关系理论,从假设到概念和推理层面,都已经无法解释和预测今天的世界,而权力小博弈理论可以为认识多元复杂互动博弈时代的国际关系提供一个新的解释框架。 相似文献
2.
In this article, we propose a novel approach for testing the equality of two log-normal populations using a computational approach test (CAT) that does not require explicit knowledge of the sampling distribution of the test statistic. Simulation studies demonstrate that the proposed approach can perform hypothesis testing with satisfying actual size even at small sample sizes. Overall, it is superior to other existing methods. Also, a CAT is proposed for testing about reliability of two log-normal populations when the means are the same. Simulations show that the actual size of this new approach is close to nominal level and better than the score test. At the end, the proposed methods are illustrated using two examples. 相似文献
3.
When a candidate predictive marker is available, but evidence on its predictive ability is not sufficiently reliable, all‐comers trials with marker stratification are frequently conducted. We propose a framework for planning and evaluating prospective testing strategies in confirmatory, phase III marker‐stratified clinical trials based on a natural assumption on heterogeneity of treatment effects across marker‐defined subpopulations, where weak rather than strong control is permitted for multiple population tests. For phase III marker‐stratified trials, it is expected that treatment efficacy is established in a particular patient population, possibly in a marker‐defined subpopulation, and that the marker accuracy is assessed when the marker is used to restrict the indication or labelling of the treatment to a marker‐based subpopulation, ie, assessment of the clinical validity of the marker. In this paper, we develop statistical testing strategies based on criteria that are explicitly designated to the marker assessment, including those examining treatment effects in marker‐negative patients. As existing and developed statistical testing strategies can assert treatment efficacy for either the overall patient population or the marker‐positive subpopulation, we also develop criteria for evaluating the operating characteristics of the statistical testing strategies based on the probabilities of asserting treatment efficacy across marker subpopulations. Numerical evaluations to compare the statistical testing strategies based on the developed criteria are provided. 相似文献
4.
In studies with recurrent event endpoints, misspecified assumptions of event rates or dispersion can lead to underpowered trials or overexposure of patients. Specification of overdispersion is often a particular problem as it is usually not reported in clinical trial publications. Changing event rates over the years have been described for some diseases, adding to the uncertainty in planning. To mitigate the risks of inadequate sample sizes, internal pilot study designs have been proposed with a preference for blinded sample size reestimation procedures, as they generally do not affect the type I error rate and maintain trial integrity. Blinded sample size reestimation procedures are available for trials with recurrent events as endpoints. However, the variance in the reestimated sample size can be considerable in particular with early sample size reviews. Motivated by a randomized controlled trial in paediatric multiple sclerosis, a rare neurological condition in children, we apply the concept of blinded continuous monitoring of information, which is known to reduce the variance in the resulting sample size. Assuming negative binomial distributions for the counts of recurrent relapses, we derive information criteria and propose blinded continuous monitoring procedures. The operating characteristics of these are assessed in Monte Carlo trial simulations demonstrating favourable properties with regard to type I error rate, power, and stopping time, ie, sample size. 相似文献
5.
Bioequivalence (BE) studies are designed to show that two formulations of one drug are equivalent and they play an important role in drug development. When in a design stage, it is possible that there is a high degree of uncertainty on variability of the formulations and the actual performance of the test versus reference formulation. Therefore, an interim look may be desirable to stop the study if there is no chance of claiming BE at the end (futility), or claim BE if evidence is sufficient (efficacy), or adjust the sample size. Sequential design approaches specially for BE studies have been proposed previously in publications. We applied modification to the existing methods focusing on simplified multiplicity adjustment and futility stopping. We name our method modified sequential design for BE studies (MSDBE). Simulation results demonstrate comparable performance between MSDBE and the original published methods while MSDBE offers more transparency and better applicability. The R package MSDBE is available at https://sites.google.com/site/modsdbe/ . Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
6.
中小企业在国民经济中占有重要的地位.随着经济全球化和社会分工的发展,中小企业的国际化经营已成必然趋势.本文分析了我国中小企业国际化经营存在的问题,提出了相应的对策建议. 相似文献
7.
以城市为主导统筹城乡、区域和谐发展 总被引:4,自引:0,他引:4
程必定 《青岛科技大学学报(社会科学版)》2005,21(1):9-12
长期以来,我国的区域经济实际上是农村主导型的发展模式。现在,这种发展模式已经走到了尽头,必然要向城市主导型区域经济发展模式的转变。这就要求区域经济发展应以城市为重点,推进城市化战略,统筹城乡发展,在此基础上构筑城市经济圈,统筹区域发展。城市经济圈的形成应打破行政界限,顺其自然地构建城市经济圈,因市制宜地探索城市经济圈的发展道路,逐步提升城市经济发展水平,以城市为主导统筹区域经济协调发展。 相似文献
8.
针对市场中介组织的发展现状及存在的问题 ,着重从组织形式和服务内容两个方面 ,研究了发展为中小企业提供人力资源开发服务市场中介组织的目标模式 ,并提出了发展该类中介组织的对策措施 相似文献
9.
股份合作制有其制度优势,特别适合小企业,资本与劳动的矛盾不是股份合作制的制度障碍,并对股权设置中的共有产权、资本与劳动关系、经营者积极性、治理结构、转让与筹资等问题提出我们的改进思路与方法。 相似文献
10.
喻学才 《东南大学学报(哲学社会科学版)》2002,4(2):51-54
作为墨家学派创始人的墨子是广为人知的,但作为和鲁 班齐名的古代著名工匠和军事建筑家的墨子,则鲜为人知。墨子在小城防守方面的贡献,既 有理论又有实践,在中国军事史和中国建筑史上都应占有重要的地位。 相似文献