The problems of estimating population total in MPPS surveys are considered.There are three models which are appropriate to different correlation coefficient between the study variable y and the auxiliary variable x.Some of the proposed estimators are found superior to Hansen-Hurwitz’s estimator.At last,we suggest a estimator of population correlation coefficient.
In this article,we consider linear transformation using minimum and maximum values of the auxiliary variable and obtain two new ratio estimators.The efficiency of different ratio estimation are compared and then we present the rules of choosing efficient estimator in different situations.
