Neyman Allocation

When you specify the ALLOC=NEYMAN option, PROC SURVEYSELECT allocates the total sample size among the strata in proportion to stratum sizes and stratum variances. Neyman allocation is a special case of optimal allocation, where the costs per unit are the same for all strata. For Neyman allocation, the proportion of the total sample size for stratum is computed as

The target sample size for stratum is . The are converted to integer sample sizes by using a rounding algorithm that requires the sum of the stratum sizes to equal . The final sample sizes are required to be at least 1, or at least if you specify a minimum sample size with the ALLOCMIN= option. For without-replacement selection methods, the final sample sizes must not exceed the stratum sizes.