What is the first step in carrying out stratified sampling?

The first step in carrying out stratified sampling is to identify the strata. Strata are distinct subgroups within a population that share similar characteristics. This might include factors like age, gender, income level, or educational attainment, among others. By defining these subgroups, researchers ensure that they can adequately represent the diversity within the larger population.

Once the strata are identified, the researcher can then proceed to determine how many samples to take from each stratum, or the sample size, which could be influenced by the proportion of each stratum in the population. This systematic approach allows for more precise and representative sampling, leading to more reliable results in the research.

The other steps listed are essential but come after establishing the strata, making identifying the strata the foundational first step in the stratified sampling process.