Stratified random sampling is a method of sampling that divides a population into smaller groups that form the basis of test samples.

A simple random sample is used to represent the entire data population. A stratified random sample divides the population into smaller groups based on shared characteristics.

Stratified Random Sampling – If you suspect there are unique differences between items in your population, you might use this sampling strategy to ensure you get a balanced representation of the ...

Richard Valliant, Generalized Variance Functions in Stratified Two-Stage Sampling, Journal of the American Statistical Association, Vol. 82, No. 398 (Jun., 1987), pp. 499-508 ...