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排序方式: 共有1614条查询结果,搜索用时 15 毫秒
1.
在刑事非法证据排除规则的具体运用中,"非法证据"的界定是当然前提。非法证据并非是任一证据合法性要件欠缺的广义非法证据,而专指取证主体通过严重非法的手段或者侵犯公民基本权利的方式所获取的证据材料。我国刑事非法证据包括非法言词证据和非法实物证据两类,两类非法证据在实际判断中虽存在差异,但都应围绕取证手段的非法性展开,分别考察取证手段是否违反法律规定以及违法的严重程度,以准确界定刑事非法证据的范围。  相似文献   
2.
When a candidate predictive marker is available, but evidence on its predictive ability is not sufficiently reliable, all‐comers trials with marker stratification are frequently conducted. We propose a framework for planning and evaluating prospective testing strategies in confirmatory, phase III marker‐stratified clinical trials based on a natural assumption on heterogeneity of treatment effects across marker‐defined subpopulations, where weak rather than strong control is permitted for multiple population tests. For phase III marker‐stratified trials, it is expected that treatment efficacy is established in a particular patient population, possibly in a marker‐defined subpopulation, and that the marker accuracy is assessed when the marker is used to restrict the indication or labelling of the treatment to a marker‐based subpopulation, ie, assessment of the clinical validity of the marker. In this paper, we develop statistical testing strategies based on criteria that are explicitly designated to the marker assessment, including those examining treatment effects in marker‐negative patients. As existing and developed statistical testing strategies can assert treatment efficacy for either the overall patient population or the marker‐positive subpopulation, we also develop criteria for evaluating the operating characteristics of the statistical testing strategies based on the probabilities of asserting treatment efficacy across marker subpopulations. Numerical evaluations to compare the statistical testing strategies based on the developed criteria are provided.  相似文献   
3.
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   
4.
提出了一种基于小波变换的管理数据处理方法,把公司管理上的数据看成一个非平稳的时间序列,利用小渡函数将该时间序列分解到不同的频率通道上,然后将分解后的信号当作近似的平稳时间序列,用一些传统的统计方法进行预测,同时对中国足球彩票若干期的销售量数据进行了处理和预测,并将结果与实际销量以及用传统的AR模型的预测值进行了比较。  相似文献   
5.
随着科学技术的进步和计算机的广泛运用 ,电子证据在刑事诉讼活动和证明过程中占有日益显著的地位。作为对新生事物的关注 ,我国法学理论界对电子证据的法律地位、种类归属及证据力等问题的研究在近年内也缓慢起步。因此 ,当前有必要从电子证据的收集与提取、资格与归属、认证与证明力各环节出发 ,对电子证据进行更加深入的理论分析和探讨 ,从而作出新的立法构想与安排 ,以弥补旧有制度的缺陷 ,并适应社会进步和国际发展趋势。  相似文献   
6.
非统计专业统计学教育刍议   总被引:1,自引:0,他引:1  
针对非统计专业统计学教育目前存在的问题,阐述了提高对统计学重要性的认识是保证统计教学效果的前提;统计学教学环节的改革是提高教学效果的重要保证;统计教师的业务素质是提高统计教学效果的关键。  相似文献   
7.
Children may be more susceptible to toxicity from some environmental chemicals than adults. This susceptibility may occur during narrow age periods (windows), which can last from days to years depending on the toxicant. Breathing rates specific to narrow age periods are useful to assess inhalation dose during suspected windows of susceptibility. Because existing breathing rates used in risk assessment are typically for broad age ranges or are based on data not representative of the population, we derived daily breathing rates for narrow age ranges of children designed to be more representative of the current U.S. children's population. These rates were derived using the metabolic conversion method of Layton (1993) and energy intake data adjusted to represent the U.S. population from a relatively recent dietary survey (CSFII 1994–1996, 1998). We calculated conversion factors more specific to children than those previously used. Both nonnormalized (L/day) and normalized (L/kg-day) breathing rates were derived and found comparable to rates derived using energy estimates that are accurate for the individuals sampled but not representative of the population. Estimates of breathing rate variability within a population can be used with stochastic techniques to characterize the range of risk in the population from inhalation exposures. For each age and age-gender group, we present the mean, standard error of the mean, percentiles (50th, 90th, and 95th), geometric mean, standard deviation, 95th percentile, and best-fit parametric models of the breathing rate distributions. The standard errors characterize uncertainty in the parameter estimate, while the percentiles describe the combined interindividual and intra-individual variability of the sampled population. These breathing rates can be used for risk assessment of subchronic and chronic inhalation exposures of narrow age groups of children.  相似文献   
8.
A test of congruence among distance matrices is described. It tests the hypothesis that several matrices, containing different types of variables about the same objects, are congruent with one another, so they can be used jointly in statistical analysis. Raw data tables are turned into similarity or distance matrices prior to testing; they can then be compared to data that naturally come in the form of distance matrices. The proposed test can be seen as a generalization of the Mantel test of matrix correspondence to any number of distance matrices. This paper shows that the new test has the correct rate of Type I error and good power. Power increases as the number of objects and the number of congruent data matrices increase; power is higher when the total number of matrices in the study is smaller. To illustrate the method, the proposed test is used to test the hypothesis that matrices representing different types of organoleptic variables (colour, nose, body, palate and finish) in single‐malt Scotch whiskies are congruent.  相似文献   
9.
统计执法的博弈分析   总被引:1,自引:0,他引:1  
针对目前中国统计数据失真相当严重并引起社会各界普遍关注的现象,运用博弈论作为分析工具,引入重复博弈研究了统计执法中数据报方与查方的利益冲突关系,从统计执法的角度揭示了统计数据失真的主要原因,并提出了相应的五项对策。  相似文献   
10.
We present and justify a propagation algorithm to facilitate the simultaneous calculation, for every node in a probabilistic exper system of the distribution of the associated random quantity, conditional on all the evidence obtained about the remaining nodes.  相似文献   
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