What type of sampling involves segmenting the market before collecting data?

Stratified sampling is the method that involves segmenting the market before collecting data. This approach divides the population into distinct subgroups or strata, which are typically based on shared characteristics or attributes that are relevant to the research. These characteristics can include factors like age, income, education level, or any other variable that might impact the research outcomes.

By stratifying the population, researchers ensure that each subgroup is adequately represented within the sample. This leads to more precise and reliable results, as it allows for a more accurate reflection of the diversity within the total population. When data is collected from each stratum, it enhances the ability to compare differences across groups, improving the overall quality of the insights gathered from the study.

In contrast, random sampling involves selecting individuals from the overall population without regard for any specific subgroups, which can lead to unequal representation. Convenience sampling focuses on selecting individuals who are easily accessible, and purposive sampling targets specific groups due to particular characteristics or needs, but neither of these methods systematically addresses segments of the market in the same structured way that stratified sampling does.