Karamikabir H, Afshari M, Lak F
Department of Statistics, Persian Gulf University, Bushehr, Iran.
J Appl Stat. 2020 Jun 9;48(10):1712-1729. doi: 10.1080/02664763.2020.1772209. eCollection 2021.
In this paper, the problem of estimating the mean vector under non-negative constraints on location vector of the multivariate normal distribution is investigated. The value of the wavelet threshold based on Stein's unbiased risk estimators is calculated for the shrinkage estimator in restricted parameter space. We suppose that covariance matrix is unknown and we find the dominant class of shrinkage estimators under Balance loss function. The performance evaluation of the proposed class of estimators is checked through a simulation study by using risk and average mean square error values.
本文研究了在多元正态分布位置向量的非负约束下估计均值向量的问题。针对受限参数空间中的收缩估计量,计算了基于斯坦无偏风险估计器的小波阈值。我们假设协方差矩阵未知,并在平衡损失函数下找到了收缩估计量的主导类。通过使用风险和平均均方误差值的模拟研究,对所提出的估计器类进行了性能评估。