On allocation of sample using estimates of both proportions of stratum sizes and standard deviations

Summary Stratified sampling is the most efficient when the sample is allocated to different strata in proportion to the products of (i) the proportions of the stratum sizes and (ii) the standard deviations of the variable in various strata (Neyman 2]). In practice, however, these are not always known. Sometimes, proportions of stratum sizes are not known at the planning stage but become known at the estimation stage. Comparison of various plans has been made when estimates of these measures are made use of in the allocation of sample.