Strata

From Displayr
Jump to: navigation, search

A sub-group in a population where the sub-group is to be used for the purpose of stratified random sampling. In surveys of people the most common strata are combinations of age, gender and geography (e.g., males aged 25 to 39 living in California). Strata need to be mutually exclusive and exhaustive, such that the combination of all of the strata is equivalent to the population.