Abstract:
The problem of estimating the mean of a multivariate normal distribution by different types of shrinkage estimators is investigated. We established the minimaxity of Baranchick-type estimators for identity covariance matrix and the matrix associated to the loss function is diagonal. In particular the class of James–Stein estimator is presented. The general situation for both matrices cited above is discussed.
Keywords:ñovariance matrix, James–Stein estimator, loss function, multivariate gaussian random variable, non-central chi-square distribution, shrinkage estimator.
UDC:
517.9
Received: 08.04.2020 Received in revised form: 01.06.2020 Accepted: 16.07.2020