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201.
In this article, we consider a nonparametric regression model with replicated observations based on the dependent error’s structure, for exhibiting dependence among the units. The wavelet procedures are developed to estimate the regression function. The moment consistency, the strong consistency, strong convergence rate and asymptotic normality of wavelet estimator are established under suitable conditions. A simulation study is undertaken to assess the finite sample performance of the proposed method. 相似文献
202.
We consider the properties of the trimmed mean, as regards minimax-variance L-estimation of a location parameter in a Kolmogorov neighbourhood K() of the normal distribution: We first review some results on the search for an L-minimax estimator in this neighbourhood, i.e. a linear combination of order statistics whose maximum variance in Kt() is a minimum in the class of L-estimators. The natural candidate – the L-estimate which is efficient for that member of Kt,() with minimum Fisher information – is known not to be a saddlepoint solution to the minimax problem. We show here that it is not a solution at all. We do this by showing that a smaller maximum variance is attained by an appropriately trimmed mean. We argue that this trimmed mean, as well as being computationally simple – much simpler than the efficient L-estimate referred to above, and simpler than the minimax M- and R-estimators – is at least “nearly” minimax. 相似文献
203.
Linear mixed models based on the normality assumption are widely used in health related studies. Although the normality assumption leads to simple, mathematically tractable, and powerful tests, violation of the assumption may easily invalidate the statistical inference. Transformation of variables is sometimes used to make normality approximately true. In this paper we consider another approach by replacing the normal distributions in linear mixed models by skew-t distributions, which account for skewness and heavy tails for both the random effects and the errors. The full likelihood-based estimator is often difficult to use, but a 3-step estimation procedure is proposed, followed by an application to the analysis of deglutition apnea duration in normal swallows. The example shows that skew-t models often entail more reliable inference than Gaussian models for the skewed data. 相似文献
204.
By approximating the nonparametric component using a regression spline in generalized partial linear models (GPLM), robust generalized estimating equations (GEE), involving bounded score function and leverage-based weighting function, can be used to estimate the regression parameters in GPLM robustly for longitudinal data or clustered data. In this paper, score test statistics are proposed for testing the regression parameters with robustness, and their asymptotic distributions under the null hypothesis and a class of local alternative hypotheses are studied. The proposed score tests reply on the estimation of a smaller model without the testing parameters involved, and perform well in the simulation studies and real data analysis conducted in this paper. 相似文献
205.
One classical design criterion is to minimize the determinant of the covariance matrix of the regression estimates, and the designs are called D-optimal designs. To reflect the nature that the proposed models are only approximately true, we propose a robust design criterion to study response surface designs. Both the variance and bias are considered in the criterion. In particular, D-optimal minimax designs are investigated and constructed. Examples are given to compare D-optimal minimax designs with classical D-optimal designs. 相似文献
206.
省域内多地区投入产出表的编制和更新:江苏案例 总被引:1,自引:0,他引:1
运用地区投入产出表解释区域内经济的空间关联特征及演化规律已成为当今区域经济研究的一个重要研究方向,但目前我国省域内多地区投入产出表的编制和应用研究尚少见。本文以《江苏投入产出表》(1987年和2002年)、1987年江苏部分地级市地区投入产出表和《江苏统计年鉴》等数据为基础,编制和更新了1987年和2002年江苏省苏南、苏中、苏北3个区域、30个部门的省域内区域间投入产出表。论文的关键技术包括:通过计算全要素生产率(TFP)形式的差异推算出直接消耗系数矩阵;通过引力模型来推算区域间流入流出的贸易系数矩阵;通过交叉熵(CE)技术,使得直接消耗系数矩阵的更新在已有信息条件下信息损失最小化。 相似文献
207.
208.
周淑荣 《华中农业大学学报(社会科学版)》2000,(1):19-20
编者按 邯钢经验引起全国上下的高度重视,引导了一个时期国有企业改革与发展的方向,值得我们认真总结. 相似文献
209.
泛珠三角经济圈欠发达地区经济发展研究 总被引:1,自引:0,他引:1
“十一五”期间加快泛珠三角经济圈欠发达地区经济发展,既是落实科学发展观、全面建设小康社会、促进我国区域经济协调发展的需要,又是促进泛珠三角区域经济板块形成不可或缺的一环。在国际国内区域经济合作蓬勃展开的背景下,本文认为泛珠三角经济圈欠发达地区应该通过区域经济合作构建开放型经济,培育新的核心区,实施跨越式发展,缩小地区差距,促进区域经济协调发展,并提出了若干对策。 相似文献
210.
Farmers’ adaptability to the policy of ecological protection in China—A case study in Yanchi County,China 总被引:1,自引:0,他引:1
Due to long-term human activities, grassland ecosystems have been severely damaged. To protect grassland ecosystems, the prohibited grazing policy (PGP), a grassland ecological protection policy, was instituted for Chinese grasslands in 2002. However, it is unknown whether farmers have effectively adapted to the PGP. The adaptability of farmers to this policy has directly influenced the effective implementation of the policy and the sustainable development of the ecosystem. Previous research on adaptability has not focused on the adaptation to political change. This article uses a case study in Northwest China to investigate the adaptability of farmers to the policy. First, we study the restoration status of ecosystems. In addition, this paper studies the perceptions regarding farmers’ adaptability to the policy and explores the adaptation strategies of different types of farmers. Finally, this paper discusses the main factors that influence farmers’ choice of adaptation strategies. The implementation of the PGP has achieved remarkable ecological benefits. Farmers of different types had different adaptation perceptions, and their choices of adaptation strategies also varied. In addition to the farmers’ perception of the policy, the main factors that influenced farmers’ adaptation strategies also included livelihood capital. 相似文献