Local Influence of Liu Estimators in Elliptical Semiparametric Linear Models

We present diagnostic methods for Liu estimators under elliptical semiparametric linear model based on the pseudo-likelihood function. The maximum likelihood esti- mators of the parameters in the Liu estimators are given and local influence measures are developed. The diagnostics under the perturbations variance and assessing the influence on the selection of the Liu penalized least squares estimators parameter are derived