非平衡随机效应模型中方差分量的经验Bayes估计

对非平衡单向分类随机效应模型中方差分量找到了其最小充分统计量,在加权平方损失下导出了其Bayes估计,利用多元密度及其偏导数的核估计方法构造了方差分量的经验Bayes(EB)估计,并导出了其收敛速度.文末用例子说明了符合定理条件的先验分布是存在的.     

单向分类随机效应模型中方差分量的渐近最优经验Bayes估计

本文在加权平方损失下导出了单向分类随机效应模型中方差分量的Bayes估计, 利用多元密度及其偏导数的核估计方法构造了方差分量的经验Bayes(EB)估计,证明了 EB估计的渐近最优性.文末还给出了一个例子说明了符合定理条件的先验分布是存在 的.     

随机效应模型中方差分量渐近最优的经验Bayes估计

本文在加权二次损失下导出了双向分类随机效应模型中方差分量的Bayes估计,并利用多元密度函数及其混合偏导数核估计的方法构造了方差分量的经验Bayes(EB)估计.在适当的条件下证明了EB估计的渐近最优性,给出了模型的特例和推广.最后,举出一个满足定理条件的例子.     

正态-逆Wishart先验下多元线性模型中经验Bayes估计的优良性

在正态-逆Wishart先验下研究了多元线性模型中参数的经验Bayes估计及其优良性问题.当先验分布中含有未知参数时,构造了回归系数矩阵和误差方差矩阵的经验Bayes估计,并在Bayes均方误差(简称BMSE)准则和Bayes均方误差阵(简称BMSEM)准则下,证明了经验Bayes估计优于最小二乘估计.最后,进行了Monte Carlo模拟研究,进一步验证了理论结果.     

Superiority of empirical Bayes estimator of the mean vector in multivariate normal distribution

In this paper, the Bayes estimator and the parametric empirical Bayes estimator (PEBE) of mean vector in multivariate normal distribution are obtained. The superiority of the PEBE over the minimum variance unbiased estimator (MVUE) and a revised James-Stein estimators (RJSE) are investigated respectively under mean square error (MSE) criterion. Extensive simulations are conducted to show that performance of the PEBE is optimal among these three estimators under the MSE criterion.     

双指数分布位置参数的经验Bayes估计问题

本文在平方损失下导出了双指数分布位置参数的Bayes估计，利用非参数方法构造了位置参数的经验Bayes(EB)估计．在适当的条件下，获得了EB估计的收敛速度．最后，给出了一个例子说明适合定理条件的先验分布是存在的．     

On the lower bounds for mean square error of empirical bayes estimators

The usual empirical Bayes setting is considered with θ being a shift or a scale parameter. A class of empirical Bayes estimators of a function b(θ) is proposed. The properties of the estimates are studied and mean square errors are calculated. The lower bounds are constructed for mean square errors of the empirical Bayes estimators over the class of all empirical Bayes estimators of b(θ). The results are applied to the case b(θ)=θ. The examples of the upper and lower bounds for mean square error are presented for the most popular families of conditional distributions. Added to the English translaion.     

Sur les estimateurs de Bayes minimax: une méthode constructive

Bayes estimation of the mean of a multivariate normal distribution is considered under quadratic loss. We show that, when a variance mixture of normal distributions is used as a prior, superharmonicity of the square root of the marginal density provides a viable method for constructing Bayes minimax estimators. Examples illustrate the theory. In particular, we show that a scaled multivariate Student-t prior yields a proper Bayes minimax estimate.     

An extended class of minimax generalized Bayes estimators of regression coefficients

We derive minimax generalized Bayes estimators of regression coefficients in the general linear model with spherically symmetric errors under invariant quadratic loss for the case of unknown scale. The class of estimators generalizes the class considered in Maruyama and Strawderman [Y. Maruyama, W.E. Strawderman, A new class of generalized Bayes minimax ridge regression estimators, Ann. Statist., 33 (2005) 1753–1770] to include non-monotone shrinkage functions.     

平衡随机模型中方差分量的非负估计

众所周知, 对于平衡随机模型, 方差分量的方差分析估计为一致最小方差无偏估计. 本文基于方差分量的方差分析估计, 构造了一个二次不变估计类, 它包含了一些常用重要估计. 证明了该估计类在一定条件下在均方误差意义下一致优于方差分析估计, 并在此估计类基础上, 给出了方差分量的两种非负估计, 它们在均方误差意义下分别一致优于方差分析估计和限制极大似然估计, 且有显式解、容易计算.