May 2, 2024
Hamid Karamikabir

Hamid Karamikabir

Academic Rank: Assistant professor
Address: Department of Statistics, Persian Gulf University, Bushehr, Iran.
Degree: Ph.D in Statistics
Phone: 09188175368
Faculty: Faculty of Intelligent Systems and Data Science

Research

Title Low and high dimensional wavelet thresholds for matrix-variate normal distribution
Type Article
Keywords
High dimensional, Matrix-variate normal distribution, Shrinkage estimator, SURE threshold, Wavelet shrinkage method.
Journal COMMUNICATIONS IN STATISTICS-SIMULATION AND COMPUTATION
DOI https://doi.org/10.1080/03610918.2024.2326595
Researchers Hamid Karamikabir (First researcher) , Amir Sanati (Second researcher) , G.G Hamedani (Third researcher)

Abstract

The matrix-variate normal distribution is a probability distribution that is a generalization of the multivariate normal distribution to matrix-valued random variables. In this paper, we introduce a wavelet shrinkage estimator based on Stein’s unbiased risk estimate (SURE) threshold for matrix-variate normal distribution. We find a new SURE threshold for soft thresholding wavelet shrinkage estimator under the reflected normal balanced loss function in low and high dimensional cases. Also, we obtain the restricted wavelet shrinkage estimator based on non-negative sub matrix of the mean matrix. Finally, we present a simulation study to test the validity of the wavelet shrinkage estimator and two real examples for low and high dimensional data sets.