This manuscript deals with new class of almost unbiased ratio cum product estimators for the estimation of population mean of the study variable by using the known values auxiliary variable. The bias and mean squared error of proposed estimators are obtained. An empirical study is carried out to assess the efficiency of proposed estimators over the existing estimators with the help of some known natural populations and it shows that the proposed estimators are almost unbiased and it perform better than the existing estimators.

In sample surveys auxiliary information is quite often available from previous experience and using the auxiliary information several estimators are introduced like Ratio estimator modified ratio and product estimators for the estimation of population mean. This manuscript deals with the improvements on ratio cum product estimators for the estimation of population mean of the study variable by using the known values of quartiles of the auxiliary variable and their functions. The bias and mean squared error of proposed estimators are obtained. An empirical condition is developed to assess the performance of proposed estimators over the existing estimators. A numerical study is carried out to assess the efficiency of proposed estimators over the existing estimators with the help of some known natural populations. Based on the simulation study and numerical studies, the proposed estimators are less biased (almost unbiased) and it performs better than the existing estimators.