بعض مقدرات الاختبار الأولي المقلصة لمتوسط التوزيع الطبيعي

Abstract

        This paper concerned with preliminary single and double stage shrunken estimators for estimate the mean (m) of normal distribution when a prior estimate (m₀) of the actual (m) is a available using specifying shrinkage weight factors y(×) as well as pre- test region (R).

        Expression for the Bias [B(×)], Mean Squared error [MSE(×)], Efficiency [EFF(×)] and Expected sample size [E(n½s²)] for proposed estimators are derived. Numerical results and conclusions are drawn about selection different (constant) including in these expressions. Comparisons between suggested estimators with classical and some existing estimators are given in the sense of Bias and relative efficiency.