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91.
Recently Beh and Farver investigated and evaluated three non‐iterative procedures for estimating the linear‐by‐linear parameter of an ordinal log‐linear model. The study demonstrated that these non‐iterative techniques provide estimates that are, for most types of contingency tables, statistically indistinguishable from estimates from Newton's unidimensional algorithm. Here we show how two of these techniques are related using the Box–Cox transformation. We also show that by using this transformation, accurate non‐iterative estimates are achievable even when a contingency table contains sampling zeros.  相似文献   
92.
北美汉学界的《沧浪诗话》研究在主体构成上包括华裔族群和本土学者两个群体。华裔族群的代表人物是刘若愚、叶维廉、叶嘉莹、欧阳桢等人,本土学者的代表人物是加拿大的林理彰,美国的宇文所安、费维廉等人。整体上看。华裔族群的研究凸显出如下四个主要特点:一是注重影响研究,包括严羽诗论对前代文论的承传及其对后代文论(文学理论和文学批评)的影响;二是对严羽诗论系统中“以禅喻诗”批评方法及“兴趣”、“妙悟”等概念进行了阐释:三是方法上移西释中和中西对话并用;四是注意吸纳中国和日本“严学”家的研究成果。  相似文献   
93.
基于Kendall’sτ秩相关系数的优越性和定义,本文提出了新的具有明确经济意义的动态条件相关copula模型,将常用的Gaussian、Clayton和Gumbel函数统一根据该演化方程实现动态化,构造出三种Kendall’sτ动态条件相关copula模型,可用于刻画不同的相关模式。这些模型不仅参数少、容易估计,避免了现有动态条件相关copula模型构建方法各异导致的在实证中不利于比较的缺点,而且能够进行多步向前预测,有效地减少了进行样本外预测时的计算量,从而为刻画时变、非线性、非对称性和尾部相关等复杂的动态相关模式提供了新方法。  相似文献   
94.
An outlier is defined as an observation that is significantly different from the others in its dataset. In high-dimensional regression analysis, datasets often contain a portion of outliers. It is important to identify and eliminate the outliers for fitting a model to a dataset. In this paper, a novel outlier detection method is proposed for high-dimensional regression problems. The leave-one-out idea is utilized to construct a novel outlier detection measure based on distance correlation, and then an outlier detection procedure is proposed. The proposed method enjoys several advantages. First, the outlier detection measure can be simply calculated, and the detection procedure works efficiently even for high-dimensional regression data. Moreover, it can deal with a general regression, which does not require specification of a linear regression model. Finally, simulation studies show that the proposed method behaves well for detecting outliers in high-dimensional regression model and performs better than some other competing methods.  相似文献   
95.
Bayesian acceptance sampling plans, which utilize prior information on the process variation, can be employed as an alternative to conventional types of plans for taking decisions on the disposition of submitted lots. A special type of double sampling inspection plans by attributes with small acceptance numbers using Bayesian methodology is presented in this paper emphasizing its significance over small acceptance number single sampling plans. The procedures for designing such sampling plans for specified degree of discrimination which would ensure protection to the producer and consumer are discussed with illustrations under the conditions for the application of gamma-Poisson distribution.  相似文献   
96.
张云 《东方论坛》2014,(2):82-88
清代著名藏书家黄丕烈的藏书题跋于版本学、目录学等方面有很大价值,清潘祖荫、缪荃孙等人都曾搜集黄丕烈的藏书题跋,编纂成书。通过对部分黄氏手书题跋与诸家辑本的校勘,可发现后人在转抄过程中出现的讹、脱、倒、衍等问题,其中不少异文涉及是非问题。在诸家辑本基础上对黄氏藏书题跋的重新纂集校录,可为广大读者提供一个更为完整精善的本子。  相似文献   
97.
The purpose of this article is to obtain the jackknifed ridge predictors in the linear mixed models and to examine the superiorities, the linear combinations of the jackknifed ridge predictors over the ridge, principal components regression, r?k class and Henderson's predictors in terms of bias, covariance matrix and mean square error criteria. Numerical analyses are considered to illustrate the findings and a simulation study is conducted to see the performance of the jackknifed ridge predictors.  相似文献   
98.
Non‐governmental organizations (NGOs) and the government of Nepal have made some effort to reduce poverty in Nepal by creating women's affiliation groups, some of which are micro‐credit organizations. Using capabilities as defined by Amartya Sen (Development as freedom, Oxford University Press, New Delhi, 2000), which includes employment opportunities, women's ownership in productive resources such as land and/or homes, educational opportunities, and women's participation in decision‐making in the family, this study evaluated the extent to which women's ethnic group or caste affiliation affected a woman's likelihood of being empowered by participation in these groups. We analyzed a sample of 8,973 women which was taken from the 2011 Nepal Demographic and Health Survey. Previous research has demonstrated that participation in gender‐based groups is correlated with higher economic status. This study adds to the literature on women's affiliation groups by investigating the impact of structural factors, such as caste and ethnicity, on women's self‐help group participation (women's groups and credit groups).  相似文献   
99.
随着电子商务的快速发展,零售商之间竞争加剧,自有品牌战略成为零售商获取竞争优势的关键。研究拥有自有品牌零售商的平台开放策略,通过对比零售商不开放平台和开放平台下的均衡利润,给出零售商平台开放策略选择条件,并分析产品之间价格影响系数、固定成本和潜在需求差异系数对零售商平台开放策略选择的影响,最后结合数值分析和京东自有品牌的发展现状验证了本文的主要研究结论。研究发现:第一,随着固定成本的增加,佣金费率逐渐减少,随着潜在需求差异系数的增加,佣金费率逐渐增加;第二,当产品之间的价格影响系数较小(较大)时,平台开放(不开放)是零售商的最优选择;第三,当固定成本较小(较大)时,平台开放(不开放)是零售商的最优选择;第四,当潜在需求差异系数较小(较大)时,平台开放(不开放)是零售商的最优选择。  相似文献   
100.
As female labor force participation increases globally, the relationship between maternal employment and children's development remains unclear. Using data from the India Human Development Survey (2005), we investigate the link between maternal employment and children's arithmetic and reading achievement. We develop a work pattern typology that goes beyond standard measures of employment and captures work intensity and its compatibility with child-rearing in a transitional economy. We find that the relationship between maternal employment and children's outcomes is not unidimensional. For example, children of self-employed mothers are not disadvantaged compared to those with stay-at-home mothers, but maternal employment in salaried jobs or wage work outside the home is negatively associated with cognitive skills in children. However, this negative association is reversed at higher levels of maternal education, suggesting greater access to resources and flexibility associated with better jobs mitigate the negative aspects of maternal employment posed by time constraints. Additionally, maternal employment is associated with maternal involvement in schoolwork and financial investment in academic activities, providing evidence that both time and resources devoted to children's education are significant.  相似文献   
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