Abstract: The paper considers the problem of finding optimum strata boundaries to optimize the estimation of sensitive/stigmatized characters when sample sizes from different strata are allocated proportionally to strata totals of the auxiliary variable. Assuming the form of the regression of the estimation variable y on the auxiliary variable x as y=η(x)+e and the form of the conditional variance V(y∣x), the rule for finding approximate optimum strata boundaries is proposed. The limiting expression of the variance of the estimator of mean in optimum stratification has also been obtained.
Keywords: Sensitive variable, randomized response technique, construction of strata, optimum strata boundaries, limiting variance