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31.
A Semi-parametric Regression Model with Errors in Variables   总被引:4,自引:0,他引:4  
Abstract.  In this paper, we consider a partial linear regression model with measurement errors in possibly all the variables. We use a method of moments and deconvolution to construct a new class of parametric estimators together with a non-parametric kernel estimator. Strong convergence, optimal rate of weak convergence and asymptotic normality of the estimators are investigated.  相似文献   
32.
It is known that the Henderson Method III (Biometrics 9:226–252, 1953) is of special interest for the mixed linear models because the estimators of the variance components are unaffected by the parameters of the fixed factor (or factors). This article deals with generalizations and minor extensions of the results obtained for the univariate linear models. A MANOVA mixed model is presented in a convenient form and the covariance components estimators are given on finite dimensional linear spaces. The results use both the usual parametric representations and the coordinate-free approach of Kruskal (Ann Math Statist 39:70–75, 1968) and Eaton (Ann Math Statist 41:528–538, 1970). The normal equations are generalized and it is given a necessary and sufficient condition for the existence of quadratic unbiased estimators for covariance components in the considered model.  相似文献   
33.
Summary. Earthquake intensities are modelled as a function of previous activity whose specific form is based on established empirical laws in seismology, but whose parameter values can vary from place to place. This model is used for characterizing regional features of seismic activities in and around Japan, and also for exploring regions where the actual seismicity rate systematically deviates from that of the modelled rate.  相似文献   
34.
生产力内部的矛盾,使生产力有先进与落后之别。中国共产党“始终代表先进生产力的发展要求”这一论断,深化和发展了马克思主义生产力理论,从时间和空间看,生产力的先进性分别具有绝对性和相对性。社会主义初级阶段大国的国情,决定了中国共产党始终代表的是“中国的”“先进的”生产力。  相似文献   
35.
Latina female (n= 97) and Latino male (n= 69) college students (M age = 21.4 years) completed self‐report surveys regarding family of origin experiences, including sexual communication with parents while growing up. Latino parents of this comparatively highly educated sample tended to use direct rather than indirect strategies for communicating about sexuality with their children. Young women reported higher levels of sexual communication with mothers while growing up than did young men, and respondents reported less communication with fathers than mothers. Among young women, sexual communication with mother was positively associated with non‐Mexican origin and negatively associated with having older brothers living at home. In contrast, maternal education was positively associated with mother‐son communication about sex. Paternal education and the absence of older brothers positively predicted communication with both sons and daughters. The analyses provide novel information regarding sexual communication in Latino families and suggest directions for future research.  相似文献   
36.
Missing data, and the bias they can cause, are an almost ever‐present concern in clinical trials. The last observation carried forward (LOCF) approach has been frequently utilized to handle missing data in clinical trials, and is often specified in conjunction with analysis of variance (LOCF ANOVA) for the primary analysis. Considerable advances in statistical methodology, and in our ability to implement these methods, have been made in recent years. Likelihood‐based, mixed‐effects model approaches implemented under the missing at random (MAR) framework are now easy to implement, and are commonly used to analyse clinical trial data. Furthermore, such approaches are more robust to the biases from missing data, and provide better control of Type I and Type II errors than LOCF ANOVA. Empirical research and analytic proof have demonstrated that the behaviour of LOCF is uncertain, and in many situations it has not been conservative. Using LOCF as a composite measure of safety, tolerability and efficacy can lead to erroneous conclusions regarding the effectiveness of a drug. This approach also violates the fundamental basis of statistics as it involves testing an outcome that is not a physical parameter of the population, but rather a quantity that can be influenced by investigator behaviour, trial design, etc. Practice should shift away from using LOCF ANOVA as the primary analysis and focus on likelihood‐based, mixed‐effects model approaches developed under the MAR framework, with missing not at random methods used to assess robustness of the primary analysis. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
37.
员工职业发展研究   总被引:5,自引:0,他引:5  
为了实现组织对员工的有效管理 ,有必要对员工的职业发展问题有所了解。这些问题包括员工职业发展的一般概念 ,职业发展阶段及职业发展管理等  相似文献   
38.
国内学者对《宠儿》的研究不少,但涉及到黑人女性身份问题的很少。该文从女性主义和种族的角度出发,运用身份和拉康的镜像理论,对《宠儿》中三个女主人公:塞丝、贝比.萨格斯和丹芙进行分析,揭示《宠儿》中黑人女性对身份的寻求及莫里森对黑人妇女和黑人文化出路问题的探索。  相似文献   
39.
对于马克思主义“两个必然”和“两个决不会”的关系存在着“补充论”、“修正论”、“取代论”的不同观点。“两个必然”和“两个决不会”的科学论断都是社会基本矛盾运动规律的体现,二者是内在的高度统一的理论。就资本主义社会发展趋势而言,“两个决不会”具有相对性,是“两个必然”的内在要求,“两个必然”理论中包含着“两个决不会”思想,是“两个决不会”运动的最终结果。  相似文献   
40.
Longitudinal data often contain missing observations, and it is in general difficult to justify particular missing data mechanisms, whether random or not, that may be hard to distinguish. The authors describe a likelihood‐based approach to estimating both the mean response and association parameters for longitudinal binary data with drop‐outs. They specify marginal and dependence structures as regression models which link the responses to the covariates. They illustrate their approach using a data set from the Waterloo Smoking Prevention Project They also report the results of simulation studies carried out to assess the performance of their technique under various circumstances.  相似文献   
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