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61.
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.  相似文献   
62.
Bootstrap tests: how many bootstraps?   总被引:3,自引:0,他引:3  
In practice, bootstrap tests must use a finite number of bootstrap samples. This means that the outcome of the test will depend on the sequence of random numbers used to generate the bootstrap samples, and it necessarily results in some loss of power. We examine the extent of this power loss and propose a simple pretest procedure for choosing the number of bootstrap samples so as to minimize experimental randomness. Simulation experiments suggest that this procedure will work very well in practice.  相似文献   
63.
The properties of three lack-of-fit tests that are related to non-parametric cosine regression analysis are examined in the context of testing for a constant mean function. Analytic power comparisons of these tests vs a most powerful test are made using intermediate asymptotic relative efficiency. In particular, a data-driven test is produced which is asymptotically as efficient as the most powerful test over a class of alternatives. A small scale simulation experiment is conducted to ascertain the extent that the large sample comparisons are applicable to finite samples.  相似文献   
64.
In the contemporary multicentric world, sovereign states have to manage carefully the construction of their image, defining their role and aspirations. With the re-definition of the state centric politics, stories become relevant: communication is a form of power, and networked forms of communication are becoming progressively a way to conquer the transnational public spheres. Through strategic narratives of foreign politics, states try to set up the ‘tales’ of international affairs and foreign strategies, to suggest a world vision, a causal interpretation, determining frames that affect transnational actors’ position in the international environment. Sovereign states develop these kind of frame using tools and theories referred to the commercial branding tradition to promote and support their own policies and identity. We decided to investigate how that process is made through information diffusion on digital platforms.

In this work, it has been analyzed the content presented through Twitter posts by the Foreign Ministries accounts of four different States dissimilar for geopolitical positioning and security concerns (USA; Israel; France; Sweden), for a period of three months (9/1/2015-11/30/2015); leading to the identification of different models and characteristic patterns of self-representation.

The thematic content analysis, based on the identification of macrocategories and micro-issues, has led to the identification of different models and characteristic patterns of self-representation, determined by domestic vicissitudes, and has shown some regularities, caused by the branding vocation of autobiographical online contents.  相似文献   

65.
近年来周王权力问题颇受学界关注,大量成果问世。本文旨在回顾东周时期周王权力的情况,简评这一问题的研究现状,并提出对此问题的一些思考。  相似文献   
66.
The following personal reflections are in honour of Michael and all that he contributed to our lives. And, we honour Brigitte a key member of the group who died in 2006. Mem, Sue and Veronica, December 2008.  相似文献   
67.
Public and political opposition have made finding locations for new nuclear power plants, waste management, and nuclear research and development facilities a challenge for the U.S. government and the nuclear industry. U.S. government-owned properties that already have nuclear-related activities and commercial nuclear power generating stations are logical locations. Several studies and utility applications to the Nuclear Regulatory Commission suggest that concentrating locations at major plants (CLAMP) has become an implicit siting policy. We surveyed 2,101 people who lived within 50 miles of 11 existing major nuclear sites and 600 who lived elsewhere in the United States. Thirty-four percent favored CLAMP for new nuclear power plants, 52% for waste management facilities, and 50% for new nuclear laboratories. College educated, relatively affluent male whites were the strongest CLAMP supporters. They disproportionately trusted those responsible for the facilities and were not worried about existing nuclear facilities or other local environmental issues. Notably, they were concerned about continuing coal use. Not surprisingly, CLAMP proponents tended to be familiar with their existing local nuclear site. In short, likely CLAMP sites have a large and politically powerful core group to support a CLAMP policy. The challenge to proponents of nuclear technologies will be to sustain this support and expand the base among those who clearly are less connected and receptive to new nearby sites.  相似文献   
68.
新经济政策实行后,苏维埃政权对由此出现的"耐普曼"持反对态度,在认识上视它为资本主义经济成分,在政策和实践中则以限制和打击为主。这也决定了"耐普曼"最终消亡的命运。  相似文献   
69.
“政教合一制”是一种特有的政治制度,然而在对这一制度的判断标准上学界却有不同的意见,文章通过西藏地方和中世纪西欧“政教合一制”形成的比较,提出作者自己的判断标准。  相似文献   
70.
自治区自治条例研究   总被引:1,自引:0,他引:1  
民族自治地方自治机关拥有法律规定的立法权。自治机关的立法权主要是制定和变动自治条例和单行条例的权力,自治条例是民族自治地方立法机关和政府行使自治权力的法律标志。自治机关制定自治条例是全面实施民族区域自治制度的需要,是自治机关行使自治权的根本体现。由于多方面原因,到目前为止我国5个自治区无一出台自治区自治条例。制定和出台自治区自治条例必须严格遵循法律规范、法定原则和法定程序,新修改的《民族区域自治法》和西部大开发战略的实施是促成自治区自治条例尽快出台的契机。  相似文献   
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