Some Modified Exponential-Ratio Type Estimators in the presence of Non-response under Two-Phase Sampling Scheme

This paper addresses the problem of estimating the population mean using information on the auxiliary variable in the presence of non-response under two-phase sampling. A class of modified exponential-ratio type estimators using single auxiliary variable have been proposed under two different situations of non-response of the study variable. The expressions for the bias and mean square error (MSE) of a proposed class of estimators are derived. Efficiency comparisons of a proposed class of estimators with the usual unbiased estimator by Hansen and Hurwitz (1946) and other existing estimators are made. An empirical study has been carried out to judge the performances of the proposed estimators.