Calibration-based product estimator in single-and two-phase sampling

An estimator of population total is developed using the calibration approach under the assumption that the auxiliary variable is negatively correlated with the study variable. The proposed estimator outperforms the usual product estimator in terms of the criteria of bias and mean square error. An improved estimator of the variance of the proposed estimator is developed using the calibration approach a second time. The two-phase sampling case has also been dealt with. The theoretical results are demonstrated through a simulation study. © 2014 Grace Scientific Publishing, LLC.