What is the term for the subset of the population selected for detailed analysis in a study?

The term for the subset of the population selected for detailed analysis in a study is referred to as a sample. In statistical and research methodology, a sample is chosen to represent a larger population, allowing researchers to conduct their analysis and draw conclusions without needing to survey the entire population. This is particularly important when dealing with large populations where it may be impractical or impossible to gather data from every individual.

By studying a sample, researchers can make inferences about the population as a whole while managing time, resources, and logistical challenges. The quality of the sample—such as whether it is randomly selected—can significantly influence the validity of the study's results.

In contrast, the other terms mentioned are not used to describe a subset chosen for analysis. Validation refers to the process of ensuring that the methods used in the study are sound and that the findings are credible. Population refers to the entire group from which the sample is drawn, and anecdotal relates to personal accounts or stories that lack rigorous statistical or scientific evidence.