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141.
The uniformly minimum variance unbiased estimator of the cumulative hazard function in the Pareto distribution of the first kind is derived. The variance of the estimator is also obtained in an analytic form, and for some cases its values are compared numerically with mean square errors of the maximum likelihood estimator.  相似文献   
142.
科技政策评估方法是科技政策评估的操作环节,合理而科学的方法论体系可以体现出政策的价值导向,本论文试图建构一个科技政策评估的方法论体系。同时,相关性问题是科技政策评估中普遍忽视的一个重要学术问题,本文详细阐述了相关性的内在本质,并分析由相关性所导致的政策评估问题。  相似文献   
143.
毛泽东提出了为促进革命迅速取得全国胜利和组织这个胜利的各项方针、政策,运用它的基本精神改进领导作风,运用它的思想实质以提高领导艺术,充分发挥各级的组织在新时期的各项建设事业中的核心领导作用,无疑是有重要的现实的指导意义。  相似文献   
144.
Optimal designs for estimating the parameters and also the optimum factor combinations in multiresponse experiments have been considered by various authors. However, till date, in mixture experiments optimum designs have been studied only in the single response case. In this article, attempt has been made to investigate optimum designs for estimating optimum mixing proportions in a multiresponse mixture experiment.  相似文献   
145.
Severe departures from normality occur frequently for null distributions of statistics associated with applications of mulLi-response permutation procedures (MRPP) for either small or large finite populations. This paper describes the commonly encountered situation associated with asymptotic non-normality for null distributions of MRPP statistics which does not depend on the underlying multivariate distribution. In addition, this paper establishes the existence of a non-degenerate underlying distribution for which the null distributions of MRPP statistics are asymptotically non-normal for essentially all size structure configurations. It is known that MRPP statistics are symmetric versions of a broader class of statistics, most of which are asymmetric. Because of the non-normality associated with null distributions of MRPP statistics, this paper includes necessary results for inferences based on the exact first three moments of anv statistic in this broader class (analogous to existing results for MRPP statistics).  相似文献   
146.
Ranked set sampling is a procedure which may be used to improve the precision of the estimator of the mean. It is useful in cases where the variable of interest is much more difficult to measure than to order. However, even if ordering is difficult, but there is an easily ranked concomitant variable available, then it may be used to “judgment order” the original variable. The amount of increase in the precision of the estimator is dependent upon the correlation between the 2 variables.  相似文献   
147.
As the number of random variables for the categorical data increases, the possible number of log-linear models which can be fitted to the data increases rapidly, so that various model selection methods are developed. However, we often found that some models chosen by different selection criteria do not coincide. In this paper, we propose a comparison method to test the final models which are non-nested. The statistic of Cox (1961, 1962) is applied to log-linear models for testing non-nested models, and the Kullback-Leibler measure of closeness (Pesaran 1987) is explored. In log-linear models, pseudo estimators for the expectation and the variance of Cox's statistic are not only derived but also shown to be consistent estimators.  相似文献   
148.
从哲学基础、西方经济学方法论的演变过程、科学抽象法与现象抽象法、资本主义生产方式的批判学说与辩护学说四个方面阐述了《资本论》方法论与西方经济学方法论的不同;又从都注重实证分析法与规范分析法的结合和在制度分析方法上也有交叉阐述了两者的共同点。  相似文献   
149.
This article is devoted to the construction and asymptotic study of adaptive, group‐sequential, covariate‐adjusted randomized clinical trials analysed through the prism of the semiparametric methodology of targeted maximum likelihood estimation. We show how to build, as the data accrue group‐sequentially, a sampling design that targets a user‐supplied optimal covariate‐adjusted design. We also show how to carry out sound statistical inference based on such an adaptive sampling scheme (therefore extending some results known in the independent and identically distributed setting only so far), and how group‐sequential testing applies on top of it. The procedure is robust (i.e. consistent even if the working model is mis‐specified). A simulation study confirms the theoretical results and validates the conjecture that the procedure may also be efficient.  相似文献   
150.
Although low participation rates have historically been considered problematic in peer nomination research, some researchers have recently argued that small proportions of participants can, in fact, provide adequate sociometric data. The current study used a classical measurement perspective to investigate the internal reliability (Cronbach's α) of peer nomination measures of acceptance, popularity, friendship, prosocial behavior, and overt aggression. Data from 642 participants attending 10 schools were resampled at different participation rates ranging from 5 percent to 100 percent of the original samples. Results indicated that (1) the association between participation rate and Cronbach's α was curvilinear across schools and variables; (2) collecting more data for a given variable (by using unlimited vs. limited nominations, or two vs. one items) was significantly related to higher internal reliability; and (3) certain variables (overt aggression, popularity) were more reliable than others (acceptance, friendship). Implications for future research were discussed.  相似文献   
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