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11.
任务分析是任务型组织设立的前提,但是,这项工作必须是在常规组织中进行的。因为在常规组织的运行中,当出现了非常规任务的时候,才会通过设立任务型组织去解决这类任务。所以,常规组织必须拥有一种任务分析机制,去自觉地识别非常规任务。这一机制的存在,对于常规组织承担常规任务也是积极的。任务型组织设立的方式有回应性设立和前瞻性设立2种,从现实需求看,前瞻性设立将会成为越来越普遍的现象。  相似文献   
12.
Merging information for semiparametric density estimation   总被引:1,自引:0,他引:1  
Summary.  The density ratio model specifies that the likelihood ratio of m −1 probability density functions with respect to the m th is of known parametric form without reference to any parametric model. We study the semiparametric inference problem that is related to the density ratio model by appealing to the methodology of empirical likelihood. The combined data from all the samples leads to more efficient kernel density estimators for the unknown distributions. We adopt variants of well-established techniques to choose the smoothing parameter for the density estimators proposed.  相似文献   
13.
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   
14.
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   
15.
首先分析了对数最小二乘排序法的特点,说明它是一种值得重视的好方法;并进一步阐述了这一方法的基本原理,着重地对群体判断下求加权的综合排序向量的方法进行了严密的数学推导;提出了在加权的综合排序中权重系数确定的新見解,并举例子以解释。  相似文献   
16.
利用漫反射法获得环丙沙星短波近红外光谱(700-1100nm),采用化学计量学中的偏最小二乘法(PLS),选取不同的波长范围及不同的光谱预处理方法(一阶导数和和二阶导数)对光谱进行信息提取和分析,对盐酸环丙沙星粉末药品进行了无损非破坏定量分析,以样品中盐酸环丙沙星为活性成分建立了最佳的数学校正模型。讨论了主成分数对PLS模型定量预测能力的影响,并做了比较。  相似文献   
17.
Summary.  We explore the determinants of debt, financial assets and net worth at the household level by using survey data for Germany, Great Britain and the USA. To identify which households are potentially vulnerable to adverse changes in the economic environment, we also explore the determinants of a range of measures of financial pressure: the probability that a household has negative net worth; the debt-to-income ratio; mortgage income gearing; the saving-to-income ratio. Our empirical findings suggest that the poorest and the youngest households are the most vulnerable to adverse changes in their financial circumstances.  相似文献   
18.
Not having a variance estimator is a seriously weak point of a sampling design from a practical perspective. This paper provides unbiased variance estimators for several sampling designs based on inverse sampling, both with and without an adaptive component. It proposes a new design, which is called the general inverse sampling design, that avoids sampling an infeasibly large number of units. The paper provide estimators for this design as well as its adaptive modification. A simple artificial example is used to demonstrate the computations. The adaptive and non‐adaptive designs are compared using simulations based on real data sets. The results indicate that, for appropriate populations, the adaptive version can have a substantial variance reduction compared with the non‐adaptive version. Also, adaptive general inverse sampling with a limitation on the initial sample size has a greater variance reduction than without the limitation.  相似文献   
19.
普通师范院校音乐教育专业传统办学模式 ,在改革开放的今天 ,已不适应新形势的发展 ,存在着诸多弊端。为了适应我国入世的新形势和配合素质教育 ,本文针对存在的问题 ,提出了一系列教改构想 ,若能有效实施 ,必将为新形势的需要和基础音乐教育培养出新一代高素质的专业人才 ,推进中、小学素质教育向纵深发展  相似文献   
20.
The small sample performance of least median of squares, reweighted least squares, least squares, least absolute deviations, and three partially adaptive estimators are compared using Monte Carlo simulations. Two data problems are addressed in the paper: (1) data generated from non-normal error distributions and (2) contaminated data. Breakdown plots are used to investigate the sensitivity of partially adaptive estimators to data contamination relative to RLS. One partially adaptive estimator performs especially well when the errors are skewed, while another partially adaptive estimator and RLS perform particularly well when the errors are extremely leptokur-totic. In comparison with RLS, partially adaptive estimators are only moderately effective in resisting data contamination; however, they outperform least squares and least absolute deviation estimators.  相似文献   
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