Approximately optimum strata boundaries for two concomitant stratification variables under proportional allocation

Abstract The proper choice of strata boundaries is an important factor determining the efficiency estimator considered characteristics a population. In this article, Cum Rule (i=3,4) for obtaining approximately optimum has been applied, taking into account single-study variable along with two concomitant variables serving as basis stratification variables. relative proposed methods demonstrated theoretically and empirically by comparing them to selection already-existing in simulation study use proportional allocation method.