How do we use stratified sampling?

Stratified sampling involves dividing a population into distinct subgroups, or strata, that share similar characteristics, such as age, income, or education level. Once the strata are defined, researchers randomly sample from each subgroup in proportion to its size relative to the entire population. This method ensures that all subgroups are adequately represented, leading to more accurate and reliable results. It is particularly useful when researchers want to ensure that specific segments of the population are included in the sample.