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1.
Several methods exist for the problem of testing the equality of several treatments against the one-sided alternative that the treatments are better than the control. These methods include Dunnett's test, Bartholomew's likelihood-ratio test, the Abelson-Tukey-Schaafsma-Smid optimal-contrast test, and the multiple-contrast test of Mukerjee, Robertson, and Wright. A new test is proposed based on an approximation of the likelihood-ratio test of Bartholomew. This test involves using a circular cone in place of the alternative-hypothesis cone. The circular-cone test has excellent power characteristics similar to those of Bartholomew's test. Moreover, it has the advantages of being simpler to compute and may be used with unequal sample sizes.  相似文献   
2.
过失犯罪的发生在于人在认知活动中对引起过失犯罪的危险的注意的欠缺。注意是一种伴随着认知过程中的具有“前置”性的心理状态。人认识任何事物,都要首先对该事物施加注意,没有对某事物的注意就不能对其认知。因此,各种心理因素影响认知首先就要影响注意。错觉、情绪和情感、不良意志品质和思维品质、遗忘等心理影响注意,改变注意的指向,对应当注意避免的危险没有注意,或者没有充分注意,或者不能注意时,就造成了注意的欠缺,从而构成过失犯罪。注意欠缺的类型可以划分为转移型的注意欠缺、分散型的注意欠缺、不能型注意欠缺、拒斥型的注意欠缺。  相似文献   
3.
现代电子语料库已有了近50年的发展,但语料库应用于课堂教学才刚刚起步。通过近年语料库辅助课堂教学诸多实践研究,教师们不仅可以获得教学中的例句,还可引导学生们学习更地道、更准确的表达方式。  相似文献   
4.
Ranked set sampling is a sampling approach that leads to improved statistical inference in situations where the units to be sampled can be ranked relative to each other prior to formal measurement. This ranking may be done either by subjective judgment or according to an auxiliary variable, and it need not be completely accurate. In fact, results in the literature have shown that no matter how poor the quality of the ranking, procedures based on ranked set sampling tend to be at least as efficient as procedures based on simple random sampling. However, efforts to quantify the gains in efficiency for ranked set sampling procedures have been hampered by a shortage of available models for imperfect rankings. In this paper, we introduce a new class of models for imperfect rankings, and we provide a rigorous proof that essentially any reasonable model for imperfect rankings is a limit of models in this class. We then describe a specific, easily applied method for selecting an appropriate imperfect rankings model from the class.  相似文献   
5.
We introduce a new goodness-of-fit test which can be applied to hypothesis testing about the marginal distribution of dependent data. We derive a new test for the equivalent hypothesis in the space of wavelet coefficients. Such properties of the wavelet transform as orthogonality, localisation and sparsity make the hypothesis testing in wavelet domain easier than in the domain of distribution functions. We propose to test the null hypothesis separately at each wavelet decomposition level to overcome the problem of bi-dimensionality of wavelet indices and to be able to find the frequency where the empirical distribution function differs from the null in case the null hypothesis is rejected. We suggest a test statistic and state its asymptotic distribution under the null and under some of the alternative hypotheses.  相似文献   
6.
本文从心理学的角度出发,对高校学生体育兴趣的产生、特点及变化原因作了初步探究,并提出了情感教学对体育兴趣形成的重要作用。  相似文献   
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8.
This article identifies three consulting roles—helper, leader, and colleague; recommends that statistical consultants ask more questions about basic mechanisms; suggests that statistical consultants regard their primary responsibility as providing guidance about the scientific method itself; discusses the need for continuing education to help improve consulting skills; and describes Wisconsin's Master's degree examination, which was designed to help students become effective practicing statisticians.  相似文献   
9.
The purpose of this note is to indicate that Fieller's Theorem can be expressed in the matrix formulation of the general linear model. The practical consequence is that one general computer program which can estimate the parameters and test the validity of a pertinent model, can also compute confidence limits for the ratios of any linear combinations of the parameters.  相似文献   
10.
According to Pitman's Measure of Closeness, if T1and T2are two estimators of a real parameter $[d], then T1is better than T2if Po[d]{T1-o[d] < T2-0[d]} > 1/2 for all 0[d]. It may however happen that while T1is better than T2and T2is better than T3, T3is better than T1. Given q ? (0,1) and a sample X1, X2, ..., Xnfrom an unknown F ? F, an estimator T* = T*(X1,X2...Xn)of the q-th quantile of the distribution F is constructed such that PF{F(T*)-q <[d] F(T)-q} >[d] 1/2 for all F?F and for all T€T, where F is a nonparametric family of distributions and T is a class of estimators. It is shown that T* =Xj:n'for a suitably chosen jth order statistic.  相似文献   
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