Compute samples sizes at each phase of a twophase design where strata are created using the first phase.
1  dub(c1, c2, Ctot, Nh, Sh, Yh.bar)

c1 
cost per unit in phase1 
c2 
cost per unit in phase2 
Ctot 
Total variable cost 
Nh 
Vector of stratum population counts or proportions 
Sh 
Vector of stratum population standard deviations 
Yh.bar 
Vector of stratum population means 
Compute the first and second phase sample sizes for a double sampling design. A first phase sample is selected by simple random sampling (srs). Strata are formed based on information collected in the first phase. The Neyman allocation to strata of the second phase sample is computed ignoring costs. Optimal total sample sizes are computed for the first and second phases, given perunit costs for the first and second phases and a fixed total budget for both phases combined.
A list object with elements:
V1 
Variance component associated with phase1 
V2 
Variance component associated with phase2 
n1 
Phase1 sample size 
n2 
Total phase2 sample across all strata 
"n2/n1" 
Fraction that phase2 is of phase1 
ney.alloc 
Vector of stratum sample sizes for phase2 sample 
Vopt 
Variance of mean with the calculated phase1 and phase2 sample sizes 
nsrs 
Size of an srs that has cost 
Vsrs 
Variance of mean in an srs of cost 
Vratio 
Ratio of 
Ctot 
Input value of total cost 
cost.chk 
Computed value of phase1 plus phase2 sample with optimal sample sizes; should agree with Ctot 
Richard Valliant, Jill A. Dever, Frauke Kreuter
Cochran W (1977, sect. 12.3) Sampling Techniques. New York: John Wiley & Sons, Inc.
Neyman J (1938) Contribution to the theory of sampling human populations. Journal of the American Statistical Association, 33(201), 101116.
Valliant, R., Dever, J., Kreuter, F. (2013, sect. 17.5.2). Practical Tools for Designing and Weighting Survey Samples. New York: Springer.
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