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1.
ABSTRACT

The cost and time of pharmaceutical drug development continue to grow at rates that many say are unsustainable. These trends have enormous impact on what treatments get to patients, when they get them and how they are used. The statistical framework for supporting decisions in regulated clinical development of new medicines has followed a traditional path of frequentist methodology. Trials using hypothesis tests of “no treatment effect” are done routinely, and the p-value < 0.05 is often the determinant of what constitutes a “successful” trial. Many drugs fail in clinical development, adding to the cost of new medicines, and some evidence points blame at the deficiencies of the frequentist paradigm. An unknown number effective medicines may have been abandoned because trials were declared “unsuccessful” due to a p-value exceeding 0.05. Recently, the Bayesian paradigm has shown utility in the clinical drug development process for its probability-based inference. We argue for a Bayesian approach that employs data from other trials as a “prior” for Phase 3 trials so that synthesized evidence across trials can be utilized to compute probability statements that are valuable for understanding the magnitude of treatment effect. Such a Bayesian paradigm provides a promising framework for improving statistical inference and regulatory decision making.  相似文献   
2.
As important members of research teams, statisticians bear an ethical responsibility to analyze, interpret, and report data honestly and objectively. One way of reinforcing ethical responsibilities is through required courses covering a variety of ethics-related topics at the graduate level. We assessed ethics requirements for graduate-level statistics training programs in the United States for the 2013–2014 academic year using the websites of 88 universities, examining 103 biostatistics programs, and 136 statistics degree programs. We categorized programs’ ethics training requirements as required or not required. Thirty-one (35.1%) universities required an ethics course for at least some degree students. Sixty-two (25.5%) degree programs required an ethics course for at least some students. The majority (77.4%) of required courses were worth 0 or 1 credit. Of the 177 programs without an ethics requirement, 19 (10.7%) listed an ethics elective. Although a single ethics course is insufficient for instilling an ethical approach to science, degree programs that model expectations through coursework point to the value of ethics in science. More training programs should prepare statisticians to consider the ethical dimensions of their work through required coursework. Supplementary materials for this article are available online.  相似文献   
3.
Journal of Population Research - This paper details efforts to link administrative records from the Internal Revenue Service (IRS) to American Community Survey (ACS) and 2010 Census microdata for...  相似文献   
4.
Summary.  We detail a general method for measuring agreement between two statistics. An application is two ratios of directly standardized rates which differ only by the choice of the standard. If the statistics have a high value for the coefficient of agreement then the expected squared difference between the statistics is small relative to the variance of the average of the two statistics, and inferences vary little by changing statistics. The estimation of a coefficient of agreement between two statistics is not straightforward because there is only one pair of observed values, each statistic calculated from the data. We introduce estimators of the coefficient of agreement for two statistics and discuss their use, especially as applied to functions of standardized rates.  相似文献   
5.
城市森林效益与可持续性研究展望   总被引:15,自引:1,他引:14  
正确认识城市森林的功能和效益 ,探索不同管理措施对城市森林效益的影响 ,对实现城市森林的可持续性具有十分重要的意义。本文综述了城市森林对生态环境和生态过程产生的影响及生态和社会效益 ;分析了城市森林可持续性的内涵及特征 ;对城市森林可持续性模式及评价标准、城市森林生态学等领域的研究成果和发展方向进行了归纳分析。在分析目前我国城市生态环境面临的问题的基础上 ,进一步提出城市森林是构建城市绿色空间的主体。建设可持续城市森林是实现城市经济和环境可持续发展的重要途径。  相似文献   
6.
Lin  Tsung I.  Lee  Jack C.  Ni  Huey F. 《Statistics and Computing》2004,14(2):119-130
A finite mixture model using the multivariate t distribution has been shown as a robust extension of normal mixtures. In this paper, we present a Bayesian approach for inference about parameters of t-mixture models. The specifications of prior distributions are weakly informative to avoid causing nonintegrable posterior distributions. We present two efficient EM-type algorithms for computing the joint posterior mode with the observed data and an incomplete future vector as the sample. Markov chain Monte Carlo sampling schemes are also developed to obtain the target posterior distribution of parameters. The advantages of Bayesian approach over the maximum likelihood method are demonstrated via a set of real data.  相似文献   
7.
The 1998 Korean Survey of Family Income and Expenditures was used to examine the overall consumption and saving behavior of Korean baby boomers and compared the differences in consumption and saving behavior between older and younger boomers. The t -test results indicated that the younger boomers allocated a significantly higher percentage of their expenditures on food away from home, household appliances, transportation and communication than did the older boomers, whereas the older boomers spent higher amounts and allocated larger budget shares on their children's education than did the younger boomers. The results of Ordinary Least-Squares (OLS) regression analysis showed that, holding other factors constant, older boomers not only spent significantly more in the total consumption expenditures and education expenditures, but older boomers also saved significantly less than did younger boomers.  相似文献   
8.
城市品牌蕴含着巨大的经济价值和竞争优势。打造城市品牌,是每一座现代化城市谋求发展的必由之 路。常州在构建特大城市的进程中,应立足于经营城市的视角,探讨与解读“常州大学城”的品牌定位。  相似文献   
9.
We consider the assessment of outliers and influential observation in non-linear measurement error models. Residuals, leverage measures and case-deletiondiagonostics are examined. The method of local influence is also applied to the models. In particular, the perturbation of measurement error variances has been found useful in assessing the adequancy of the model assumptions. A numerical example is given to illustrate the application of the diagonostics.  相似文献   
10.
随着我国经济多元化趋势的日益增强,社会对人才的需求也逐步呈现出多类型的特点。作为直接为社会培养和输送人才的高等教育也发生了很大变化,产生了新的教育类型—高等职业教育。高等职业教育在教学目的、人才培养模式、教学过程等方面均有自己的特点。对于高职院校的俄语专业来说,它是职业教育领域的人文科学,不能套用普通高等院校的固有模式,而现有高职院校俄语专业尚未形成科学实用的教学和人才培养模式。因此,为了提高其教学水平和人才培养质量,必须进行教学改革,构建独具高职特色的课程结构。  相似文献   
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