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211.
As known, the least-squares estimator of the slope of a univariate linear model sets to zero the covariance between the regression residuals and the values of the explanatory variable. To prevent the estimation process from being influenced by outliers, which can be theoretically modelled by a heavy-tailed distribution for the error term, one can substitute covariance with some robust measures of association, for example Kendall's tau in the popular Theil–Sen estimator. In a scarcely known Italian paper, Cifarelli [(1978), ‘La Stima del Coefficiente di Regressione Mediante l'Indice di Cograduazione di Gini’, Rivista di matematica per le scienze economiche e sociali, 1, 7–38. A translation into English is available at http://arxiv.org/abs/1411.4809 and will appear in Decisions in Economics and Finance] shows that a gain of efficiency can be obtained by using Gini's cograduation index instead of Kendall's tau. This paper introduces a new estimator, derived from another association measure recently proposed. Such a measure is strongly related to Gini's cograduation index, as they are both built to vanish in the general framework of indifference. The newly proposed estimator is shown to be unbiased and asymptotically normally distributed. Moreover, all considered estimators are compared via their asymptotic relative efficiency and a small simulation study. Finally, some indications about the performance of the considered estimators in the presence of contaminated normal data are provided.  相似文献   
212.
Remote sensing of the earth with satellites yields datasets that can be massive in size, nonstationary in space, and non‐Gaussian in distribution. To overcome computational challenges, we use the reduced‐rank spatial random effects (SRE) model in a statistical analysis of cloud‐mask data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on board NASA's Terra satellite. Parameterisations of cloud processes are the biggest source of uncertainty and sensitivity in different climate models’ future projections of Earth's climate. An accurate quantification of the spatial distribution of clouds, as well as a rigorously estimated pixel‐scale clear‐sky‐probability process, is needed to establish reliable estimates of cloud‐distributional changes and trends caused by climate change. Here we give a hierarchical spatial‐statistical modelling approach for a very large spatial dataset of 2.75 million pixels, corresponding to a granule of MODIS cloud‐mask data, and we use spatial change‐of‐Support relationships to estimate cloud fraction at coarser resolutions. Our model is non‐Gaussian; it postulates a hidden process for the clear‐sky probability that makes use of the SRE model, EM‐estimation, and optimal (empirical Bayes) spatial prediction of the clear‐sky‐probability process. Measures of prediction uncertainty are also given.  相似文献   
213.
为得到双层INTER-MIG桨搅拌釜内流场特征,文章采用粒子图像测速技术(PIV)对直径为430 mm的双层改进 型INTER-MIG桨搅拌槽内流场进行了实验研究。分析了搅拌转速、相位角及轴向位置对搅拌槽内流场分布的影响。结 果表明:整个流场表现出较强轴流特性,底桨右端形成一个漩涡;转速增加引起桨叶附近湍动增强,但整体流型变化不 大;当r/R <0.48时,桨叶间轴流效果显著,有利于釜底流体向上抬升,增强整体混合效果;当r/R>0.48时,桨叶右端在 近壁面处会形成上下2股流动流体,有助于形成局部区域循环。实验结果可为工业搅拌过程提供工艺参考。  相似文献   
214.
以"自然"论文学,汉朝<淮南子>已有记载,但只言片语,语焉不详,直到魏晋鸿篇<文心雕龙>才有了真正意义上的"自然"论文学观.刘勰以"自然之道"来阐释文学创作的根本原则,从哲学本体论高度论证"文"之产生与存在的必然性、"文"与"质"的本质统一关系,并以此为核心探讨了文学创作之发生、文学风格之生成、创作自由之实现等一系列重要问题,建立了相当系统化的"文道自然"观.  相似文献   
215.
仁学思想是儒家道德哲学体系中的核心思想。司马迁通过历史研究,认识到了"仁"在治国安邦中的作用,于是对先秦仁学,特别是孔、孟仁学进行了批判性的继承和改造,孔子的仁学思想更是成为了他撰写《史记》、品评历代帝王的重要指导思想。本文将从《史记》入手,论述司马迁对先秦仁学的扬弃,并分析其伟大的历史意义和对当今构建和谐社会的借鉴价值。  相似文献   
216.
所谓规范指称"标准化的秩序"。社会规范指的是为社会成员所提供的是非标准和行为指南,因而也是人们具体行为必须要遵循的行为法则。儒家的社会规范可分为两种:一是以"德礼"为核心的积极的规范,其目的在于通过教化的力量来改变人们行为的根本态度;二是以"法刑"为核心的消极规范,其目的在于通过物理的制裁来暂时控制人们的行为。规范必须拥有其合理性。在儒家看来,社会的规范不是来自于近代社会学理论所讲的社会契约,而是来自于自然本身的秩序。因而"三纲五伦"以及"礼乐"、"刑政"等规范都体现着阴阳五行的自然法则。跟近代的社会学理论相比,儒家的社会规范具有以下的特点:其一,儒家的社会规范不是以平等的个人,而是以有差别的个人为前提;其二,儒家规范的根本目的不在于实现功利性或者效率性,而在于实现道德性;其三,儒家的规范不是为了实现社会契约,而是为了实现阴阳五行的自然秩序。  相似文献   
217.
"三元"说是陈衍针对今人强分唐宋诗与扬唐抑宋的诗学观所提出的诗学纠偏策略.它以三元皆盛之论,将唐宋诗并列,同时又立足于宋诗,特别以杜、韩、黄为重心,突出宋诗对唐诗的创变与突破,从而确立宋诗地位与特征,对扬唐抑宋诗学观进行纠偏.这一诗学之根本,不在纠缠于诗歌诗艺形式上的高下判别,而关注内容精神之追求.以提倡变风变雅、振兴诗教为旨归,寄寓着关注现实人生的重要的诗学思想.  相似文献   
218.
To incorporate newcomers into membership, a group employs socialization strategies to transform the characteristics of the newcomers, so that it can admit them with the confidence that their behaviour will not endanger group unity. Analyses of socialization emphasize that novices' interiorization of an institutional definition of group behaviour is a necessary condition to ensure successful socialization. The contemporary Religious Society of Friends in Britain, however, is a non-doctrinal religious movement that avoids defining the content of its beliefs and practices. To analyse the socializing interaction between members and newcomers in this movement in Britain, and among co-religionists in the USA, this inquiry applies a model of socialization that does not include assumptions about the role played by cognition in socialization (Long and Hadden 1983). My results show that: (a) the diffuseness in Friends' collective explanations of institutional conduct supports novices' identification with institutional practice, and (b) experimental and affective components in socialization motivate novices to imitate institutional behaviour despite the fact that Friends have no authoritative explanations of such behaviour. The data suggest that socialization and social cohesion are not necessarily as strongly cognitive-oriented phenomena as they were previously thought to be. This finding has important implications for thinking about social cohesion in postmodern society.  相似文献   
219.
中小企业是国民经济中最具活力的组成部分,日本和韩国作为亚洲中小企业发展较早的国家,在其政策措施、技术创新、融资担保、培训咨询、社会化服务体系方面都有独到之处;而我国中小企业的发展需要有高强度的政府政策来扶持,完善的政策法规和多样的融资政策为支撑,以产业集群为载体,搭建技术创新服务平台,扶持和巩固现有的中小企业培训机构,建立全方位的社会化服务体系。  相似文献   
220.
The two-group discriminant problem has applications in many areas, for example, differentiating between good credit risks and poor ones, between promising new firms and those likely to fail, or between patients with strong prospects for recovery and those highly at risk. To expand our tools for dealing with such problems, we propose a class of nonpara-metric discriminant procedures based on linear programming (LP). Although these procedures have attracted considerable attention recently, only a limited number of computational studies have examined the relative merits of alternative formulations. In this paper we provide a detailed study of three contrasting formulations for the two-group problem. The experimental design provides a variety of test conditions involving both normal and nonnormal populations. Our results establish the LP model which seeks to minimize the sum of deviations beyond the two-group boundary as a promising alternative to more conventional linear discriminant techniques.  相似文献   
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