Generalized Exponential Estimators for Population Variance Under Two-Phase Sampling

In this study, two-phase sampling is considered for estimating the population variance of study variable taking two auxiliary variables. The proposed generalized estimator and class of estimators are the exponential function of auxiliary variables. The mean square errors and biases equations have been obtained for the proposed estimators. The conditions for which proposed estimators are more efficient as compared to other estimators have been discussed. The empirical study showed that proposed estimators are more efficient as compared to the unbiased sample variance estimator, double sampling version of Isaki (J Am Stat Assoc 78:117–123, 1983) and Singh et al. (Ital. J. Pure Appl. Math. 28(N):101–108, 2011) generalized estimator.