Sampling

When a researcher opts to study a given phenomenon, the researcher ultimately wishes to know something about that phenomenon in a population. However, in practice we, as life-span researchers, study the phenomenon of interest within a group of individuals who purportedly represent the target or reference population to whom we wish our results to generalize. That is, we sample the population. We do so because we do not have the resources, in terms of time, money, and personnel, to assess the entire population of interest. Sampling is therefore a key feature of every study in life-span science that has far-reaching implications. This entry describes the two main categories of sampling strategies as well as each category’s subtypes. Also discussed are the relative advantages and disadvantages ...