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61.
A sample size justification should be given for all clinical investigations. However, sometimes the objective of a trial is to estimate an effect with a view to planning a later definitive study. This paper describes the calculations for designing studies where one wishes to adopt an estimation approach through using confidence intervals around the overall response. Calculations are given for data anticipated to take a Normal form. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
62.
采用蛋白组学方法,利用4例中国肺癌患者的切除肺癌组织测定了磷癌(SQCLC)的蛋白表达 从双向电泳(2-DEgel)切下53个点,49个蛋白与数据库搜索结果吻合。在鉴定的24个蛋白中,17个蛋白有报道是与肺癌相关的蛋白其7个蛋白与人类其它癌症相关。所建立的蛋白组学方法能够用于建立一种基于组织的化验方法,发现肺癌患者组织中表达的蛋白标记物以用于癌症的分子学诊断。 相似文献
63.
Estimated associations between an outcome variable and misclassified covariates tend to be biased when the methods of estimation that ignore the classification error are applied. Available methods to account for misclassification often require the use of a validation sample (i.e. a gold standard). In practice, however, such a gold standard may be unavailable or impractical. We propose a Bayesian approach to adjust for misclassification in a binary covariate in the random effect logistic model when a gold standard is not available. This Markov Chain Monte Carlo (MCMC) approach uses two imperfect measures of a dichotomous exposure under the assumptions of conditional independence and non-differential misclassification. A simulated numerical example and a real clinical example are given to illustrate the proposed approach. Our results suggest that the estimated log odds of inpatient care and the corresponding standard deviation are much larger in our proposed method compared with the models ignoring misclassification. Ignoring misclassification produces downwardly biased estimates and underestimate uncertainty. 相似文献
64.
Professor Stephen Senn Dr Dipti Amin Professor Rosemary A. Bailey Professor Sheila M. Bird FFPH Dr Barbara Bogacka Mr Peter Colman Dr rew Garrett Professor rew Grieve Professor Sir Peter Lachmann FRS FMedSci 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2007,170(3):517-579
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Has the image of Che Guevara lost its power to evoke radical politics in the face of pervasive commodification? The commercialization of this 1960s political icon has called into question the power of the market to shape collective memories. Meanwhile, antisystemic movements of the left continue to erect his image at protest events. In light of this contest over how Che Guevara is remembered, we investigate, using data from a survey of Spanish citizens, who is most likely to recall him. We find qualified support for the theory of generational imprinting—Che is more often recalled by those generations who saw him rise to prominence during their formative years, although prominent as a collective symbol rather than as a living person. Our results also corroborate the claim that historical figures or events are more salient for, and therefore more likely to be remembered by, some subgenerational units than others. Thus, although the younger generations are in general more likely than their elders to recall Che, he is most frequently remembered by the highly educated leftists who espouse postmaterialist and posttraditionalist values and identify more with their local regions than with the nation of Spain. These patterns suggest that, in contrast to the dire predictions of mass culture theorists, the memory of Che Guevara has become increasingly tied to markers of social, ethnic‐regional, and political identity. 相似文献
68.
Peter Ashby 《Social Policy & Administration》1985,19(3):191-198
In July 1985 the National Council for Voluntary Organisations launched a campaign for "action for the forgotten million"— the four out of every five long-term unemployed people who receive no practical support from the public services, apart from their benefits. The author of the National Council discussion document outlines some of the major issues which will need to be faced. In particular, he argues that public debate tends to concentrate too narrowly on specific initiatives and individual programmes. Instead, there is a need to consider the rights of all long-term unemployed people, and the needs of the group as a whole. 相似文献
69.
For a wide variety of applications, experiments are based on units ordered over time or space. Models for these experiments generally may include one or more of: correlations, systematic trends, carryover effects and interference effects. Since the standard optimal block designs may not be efficient in these situations, orthogonal arrays of type I and type II, which were introduced in 1961 by C.R. Rao [Combinatorial arrangements analogous to orthogonal arrays, Sankhya A 23 (1961) 283–286], have been recently used to construct optimal and efficient designs for many of these experiments. Results in this area are unified and the salient features are outlined. 相似文献
70.
职业地位取得的社会性别差异 总被引:6,自引:0,他引:6
本文从描述被调查夫妇之间职业流动的性别差异出发,分别勾画出他们的地位实现模型。首先验证了不论性别,教育地位都是决定职业地位实现的首要变量;但也正是在教育地位的实现和向上流动(再求学)中,伴随婚姻生育等生命事件的发生,无形的结构性制度因素(意识形态层面的性别制度、性别规范和性别文化)正如后现代主义试图解构的那样依然支配着性别角色的社会化和继续社会化,使扮演双重角色的妻子或无意识地或有意识地遭遇了丈夫不为之所累的两难困境,并最终阻碍了女性的教育地位、既而是职业地位的实现。本文最后提出了三点建议和几个尚待解决的问题。 相似文献