Definitions for "Stratified sample"
Subset of a population selected according to some important characteristic. RT stratification.
A group of people or things chosen so that certain levels or smaller groupings (like certain ages, incomes, or diagnoses) are kept together and a set number of people or things from each level are in the larger group. A stratified “random sample” chooses the people or things within each grouping or level by chance, but decides ahead of time how many people or things there will be within each level and what the levels will be.
The sample that is formed when independent random samples are selected from each stratum (or cell) of a stratified sampling design. (Also see stratification.)
Keywords:  circumstances, device, useful
a useful device in such circumstances