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81.
This article looks at STTEP, an outreach project currently housed at the University of Pretoria, which concentrates on the teaching of western orchestral instruments, plus background areas such as music theory, to disadvantaged children and youth from a variety of townships around Pretoria, South Africa. STTEP’s direction can well be described as ‘right’ – pupils are already surrounded by all kinds of global phenomena, and their formal music studies in western classical music are not making them forget their roots. In fact, the contrary has been found to be the case and some interesting cultural fusions are already seen – always a sign of a living culture.  相似文献   
82.
The International Conference on Harmonisation guideline ‘Statistical Principles for Clinical Trials’ was adopted by the Committee for Proprietary Medicinal Products (CPMP) in March 1998, and consequently is operational in Europe. Since then more detailed guidance on selected topics has been issued by the CPMP in the form of ‘Points to Consider’ documents. The intent of these was to give guidance particularly to non‐statistical reviewers within regulatory authorities, although of course they also provide a good source of information for pharmaceutical industry statisticians. In addition, the Food and Drug Administration has recently issued a draft guideline on data monitoring committees. In November 2002 a one‐day discussion forum was held in London by Statisticians in the Pharmaceutical Industry (PSI). The aim of the meeting was to discuss how statisticians were responding to some of the issues covered in these new guidelines, and to document consensus views where they existed. The forum was attended by industry, academic and regulatory statisticians. This paper outlines the questions raised, resulting discussions and consensus views reached. It is clear from the guidelines and discussions at the workshop that the statistical analysis strategy must be planned during the design phase of a clinical trial and carefully documented. Once the study is complete the analysis strategy should be thoughtfully executed and the findings reported. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
83.
自然经济和计划经济不可能产生宪政。市场经济是宪政产生和发展的前提和基础。市场经济产生权利观念、权利意识,促进政治法治化、民主化,要求限制政府权力,保护公民权利,产生宪法观念和宪法,培育宪政生存的社会基础———市民社会。  相似文献   
84.
从MDnte Carlo模拟的实现过程入手,首先通过对Monte Carlo方法原理的阐述来介绍该种方法。进一步结合具体的实例通过计算机进行模拟来解释Monte Carlo方法的具体实现过程。重点讨论在选择合理的数据生成过程的前提下,如何在Monte Carlo方法中减少模拟方差,从而提高估计精度,更好地应用这种方法来进行经济预测。  相似文献   
85.
Summary. In many biomedical studies, covariates are subject to measurement error. Although it is well known that the regression coefficients estimators can be substantially biased if the measurement error is not accommodated, there has been little study of the effect of covariate measurement error on the estimation of the dependence between bivariate failure times. We show that the dependence parameter estimator in the Clayton–Oakes model can be considerably biased if the measurement error in the covariate is not accommodated. In contrast with the typical bias towards the null for marginal regression coefficients, the dependence parameter can be biased in either direction. We introduce a bias reduction technique for the bivariate survival function in copula models while assuming an additive measurement error model and replicated measurement for the covariates, and we study the large and small sample properties of the dependence parameter estimator proposed.  相似文献   
86.
采用半经验的AM1方法研究了共聚物-(PPP)m-(PT)n-中性态和带电态的稳定构型,中性态下界面处的扭转角为25°时构型最稳定,带电态下界面处的扭转角为0°时构型最稳定.在AM1优化的基础上采用ZINDO方法研究共聚物界面处构象的改变对其光吸收性质的影响,计算发现共聚物-(PPP)m-(PT)n-的电子光吸收谱将依赖于界面处扭转角的变化,扭转角从0°到90°变化时,中性态下第一、二、三激发跃迁能随扭转角的增加而增加,而且随分子链长的变短和含苯环比例的增大,此种变化趋势越显著;在掺杂两个电荷的情况下,第一、二、三激发跃迁能随扭转角的增加而减小.  相似文献   
87.
In this article, we provide a brief introduction to the work of Michel Foucault. Our focus is on the major themes of Foucault's work: discourse, power/knowledge and subjectivity. We demonstrate the rich contribution that Foucauldian theory can make to public relations practice and scholarship by moving beyond a focus on excellence towards an understanding of public relations as a discourse practice with power effects.  相似文献   
88.
诗歌翻译要忠实于原作,但这并不意味着译作对原作亦步亦趋,生搬硬套。译者要在原作的制约下发挥主观能动性,进行“再创造”。“再创造”是法汉诗歌翻译中必不可少的手段,而不同的创造形式,又形成了法汉诗歌翻译中忠实性、牺牲性、叛逆性的创造风格。  相似文献   
89.
We propose four different GMM estimators that allow almost consistent estimation of the structural parameters of panel probit models with fixed effects for the case of small Tand large N. The moments used are derived for each period from a first order approximation of the mean of the dependent variable conditional on explanatory variables and on the fixed effect. The estimators differ w.r.t. the choice of instruments and whether they use trimming to reduce the bias or not. In a Monte Carlo study, we compare these estimators with pooled probit and conditional logit estimators for different data generating processes. The results show that the proposed estimators outperform these competitors in several situations.  相似文献   
90.
分析了客户/服务器模式下远程过程调用(RPC)原理及其实现方法,重点讨论了五种非正常情况下RPC的处理方法。  相似文献   
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