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191.
Ruhul Amin Ph.D. Dorothy C. Browne Dr.PH Jamir Ahmed M.A. Takanori Sato M.A. 《Child and Adolescent Social Work Journal》2006,23(2):172-195
In response to multiple problems faced by pregnant and parenting teens, many alternative school-based comprehensive programs have been established throughout the United States. By collecting data from a sample of enrollees of such a school-based comprehensive program and comparing them with data collected from a sample of non-enrollees, the present study systematically evaluates the program. The results of the study seem to suggest that the program participants were more likely to have higher educational aspiration, better reproductive health outcomes, higher contraceptive use, and more breast-feeding practice and intention than those of their non-participating counterparts. The implications of the study findings for comprehensive school-based program for pregnant and/or parenting teens are discussed.Ruhul Amin is a Senior Fellow at the Center for Health Disparities Solutions and Senior Research Scientist in the Institute for Urban Research, Morgan State University, Baltimore, MD 21239. Dorothy C. Browne is the Director of the Institute for Urban Research, Jamir Ahmed is a research assistant at the Center for Health Disparities Solutions and Takanori Sato is research assistants at the Institute for Urban Research, Morgan State University, Baltimore, MD 21239. 相似文献
192.
T. Mark Beasley Grier P. Page Jaap P. L. Brand Gary L. Gadbury John D. Mountz David B. Allison 《Journal of the Royal Statistical Society. Series C, Applied statistics》2004,53(1):95-108
Summary. Microarrays are a powerful new technology that allow for the measurement of the expression of thousands of genes simultaneously. Owing to relatively high costs, sample sizes tend to be quite small. If investigators apply a correction for multiple testing, a very small p -value will be required to declare significance. We use modifications to Chebyshev's inequality to develop a testing procedure that is nonparametric and yields p -values on the interval [0, 1]. We evaluate its properties via simulation and show that it both holds the type I error rate below nominal levels in almost all conditions and can yield p -values denoting significance even with very small sample sizes and stringent corrections for multiple testing. 相似文献
193.
陈满铭 《浙江师范大学学报(社会科学版)》2004,29(2):8-14
章法所探讨的是,篇章之条理,亦即连句成节(句群)、连节成段、连段成篇的逻辑组织.这种逻辑组织或条理,对应于宇宙人生规律,完全根源于人心之理,是人人与生俱有的.所以大多数的人,包括作者本身,对它的存在虽大都不自觉,却会自然地反映在他们的思考或作品之中.这种反映出来的逻辑组织或条理,由于对应于宇宙人生规律,就必然与探讨宇宙人生规律的哲学与科学有密切之关系.本文即择要就章法之类型、规律与转化(包括移位与转位)与"多、二、一(0)"的结构等,从中国哲学的逻辑结构中,以<周易>与<老子>两种典籍为主,一一作其哲学义涵之考辨,为章法之所以是"客观的存在",而定位为篇章之逻辑条理或结构,提出有力的证明与依据. 相似文献
194.
Strong control, conservative point estimation and simultaneous conservative consistency of false discovery rates: a unified approach 总被引:1,自引:0,他引:1
John D. Storey Jonathan E. Taylor David Siegmund 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2004,66(1):187-205
Summary. The false discovery rate (FDR) is a multiple hypothesis testing quantity that describes the expected proportion of false positive results among all rejected null hypotheses. Benjamini and Hochberg introduced this quantity and proved that a particular step-up p -value method controls the FDR. Storey introduced a point estimate of the FDR for fixed significance regions. The former approach conservatively controls the FDR at a fixed predetermined level, and the latter provides a conservatively biased estimate of the FDR for a fixed predetermined significance region. In this work, we show in both finite sample and asymptotic settings that the goals of the two approaches are essentially equivalent. In particular, the FDR point estimates can be used to define valid FDR controlling procedures. In the asymptotic setting, we also show that the point estimates can be used to estimate the FDR conservatively over all significance regions simultaneously, which is equivalent to controlling the FDR at all levels simultaneously. The main tool that we use is to translate existing FDR methods into procedures involving empirical processes. This simplifies finite sample proofs, provides a framework for asymptotic results and proves that these procedures are valid even under certain forms of dependence. 相似文献
195.
The multiple traveling salesman problem: an overview of formulations and solution procedures 总被引:1,自引:0,他引:1
Tolga Bektas 《Omega》2006
The multiple traveling salesman problem (mTSP) is a generalization of the well-known traveling salesman problem (TSP), where more than one salesman is allowed to be used in the solution. Moreover, the characteristics of the mTSP seem more appropriate for real-life applications, and it is also possible to extend the problem to a wide variety of vehicle routing problems (VRPs) by incorporating some additional side constraints. Although there exists a wide body of the literature for the TSP and the VRP, the mTSP has not received the same amount of attention. The purpose of this survey is to review the problem and its practical applications, to highlight some formulations and to describe exact and heuristic solution procedures proposed for this problem. 相似文献
196.
有关文章在谈到英语抽象名词的翻译时,往往都重在翻译实践的总结和翻译技巧的介绍。本文尝试以语义学和翻译理论来指导翻译实践,运用语义学中搭配意义和英汉对比的相关知识来重新探讨英语抽象名词的译法。 相似文献
197.
本文提出在4发多收天线配制的MIMO系统中基于训练序列的信道估计算法,详细研究了该算法的FPGA实现。采用我们提出的FPGA实现方法可以大大减少信道估计中矩阵乘法操作。实测结果表明实现方案很好的吻合了理论值。 相似文献
198.
Abdalla T. El-Helbawy 《Journal of statistical planning and inference》1984,10(1):105-113
A general approach for comparing designs of paired comparison experiments on the basis of the asymptotic relative efficiencies, in the Bahadur sense, of their respective likelihood ratio tests is discussed and extended to factorials. Explicit results for comparing five designs of 2q factorial paired comparison experiments are obtained. These results indicate that some of the designs which require comparison of fewer distinct pairs of treatments than does the completely balanced design are, generally, more efficient for detecting main effects and/or certain interactions. The developments of this paper generalize the work of Littell and Boyett (1977) for comparing two designs of R x C factorial paired comparison experiments. 相似文献
199.
M. Aickin 《Journal of statistical planning and inference》1983,7(3):243-256
When a collection of hypotheses is to be tested it is necessary to maintain a bound on the simultaneous Type I error rate. Serial P-values are used to define a serial test that does provide such a bound. Moreover, serial P-values are meaningful in the context of multiple tests, with or without the ‘rejection-confirmation’ decisions. The method is particularly suited to the analysis of unbalanced data, especially contingency tables. 相似文献
200.
To increase the efficiency of comparisons between treatments in clinical trials, we may consider the use of a multiple matching design, in which, for each patient receiving the experimental treatment, we match with more than one patient receiving the standard treatment. To assess the efficacy of the experimental treatment, the risk ratio (RR) of patient responses between two treatments is certainly one of the most commonly used measures. Because the probability of patient responses in clinical trial is often not small, the odds ratio (OR), of which the practical interpretation is not easily understood, cannot approximate RR well. Thus, all sample size formulae in terms of OR for case-control studies with multiple matched controls per case can be of limited use here. In this paper, we develop three sample size formulae based on RR for randomized trials with multiple matching. We propose a test statistic for testing the equality of RR under multiple matching. On the basis of Monte Carlo simulation, we evaluate the performance of the proposed test statistic with respect to Type I error. To evaluate the accuracy and usefulness of the three sample size formulae developed in this paper, we further calculate their simulated powers and compare them with those of the sample size formula ignoring matching and the sample size formula based on OR for multiple matching published elsewhere. Finally, we include an example that employs the multiple matching study design about the use of the supplemental ascorbate in the supportive treatment of terminal cancer patients to illustrate the use of these formulae. 相似文献