An improved class of estimators for nite population variance

We propose an improved class of estimators in estimating the nite population variance, using the auxiliary information. The expressions for the bias and mean squared error of the proposed class of estimators are derived up to the rst order of approximation. Some estimators are also derived from a proposed class by allocating the suitable values of known parameters and identi ed as particular members of the proposed class of estimators. A numerical study is carried out to demonstrate performances of the estimators. It is observed that the proposed class of estimators is more e cient than the usual sample mean estimator, the regression estimator suggested by Isaki (1983), Shabbir and Gupta (2007), Singh and Solanki (2013b), Yadav et al. (2013), Yadav and Kadilar (2014) and Singh and Malik (2014) estimators.