JOURNAL OF APPLIED STATISTICS, cilt.39, sa.10, ss.2081-2096, 2012 (SCI-Expanded)
In this study, the necessary and sufficient conditions for the Liu-type (LT) biased estimator are determined. A test for choosing between the LT estimator and least-squares estimator is obtained by using these necessary and sufficient conditions. Also, a simulation study is carried out to compare this estimator against the ridge estimator. Furthermore, a numerical example is given for defined test statistic.