This repository contains an R script used to compute required sample sizes for estimating the mean of the natural logarithm of Zn and the areal fraction with a Zn concentration smaller than a threshold (areal fraction with Zn deficiency). The requirement is in terms of the width of a confidence interval for a given confidence level (frequentist approach). Sample sizes are also computed with a Bayesian approach and mixed Bayesian-likelihood approach in which the uncertainty about the design parameters (variance and binomial proportion) is taken into account. For the latter two approaches three criteria are used, the average width criterion, average coverage criterion and worst outcome criterion. Sample sizes are computed for the thirteen districts of the state Andhra Pradesh in India and for the 605 mandals of this state. The cycle 1 Soil Health Card data collected in 2015-2017 are used for choosing prior distribution for the precision parameter (reciprocal of variance) for computing the required sample size for estimating the mean, and for the binomial proportion parameter for computing the required sample size for estimating the areal fraction with Zn deficiency.