keywords: Ratio estimator, two-phase sampling, bias, mean square error
In this paper, modification of Adebola and Adegoke’s report on ratio estimator was suggested. The modified estimator was obtained through transformation in two cases using sample mean of auxiliary variables. Case one was when the second sample was drawn from the first sample why case two was when the second sample was drawn from the population. The bias and mean square error (MSE) of the modified ratio estimator in the two cases were obtained. The theoretical and numerical validity of the modified ratio estimator under the two cases were determined to show its superiority over some considered existing related ratio estimators. Numerical results shows that the modified ratio estimator under the two cases were more efficient than the considered existing related estimators.