The process of selecting a small number of elements from a larger identified…

Concept: In research methodology, a population is the complete, clearly defined set of elements that a study is about, and a sample is any subset of that population studied in its place. The procedure by which such a subset is drawn from the population is sampling — a selection step, distinct from the instruments used to collect data and from the procedures used to measure responses.

Application: The stem describes taking a small number of elements out of a larger, already identified group of elements. The larger identified group is the population, the small number of elements drawn from it is the sample, and the process that produces that sample is therefore sampling.

Cross-check: separate the four terms by the stage of research each belongs to.

• Questionnaire — a data-collection instrument: a fixed, ordered set of written items administered to respondents so that their replies are recorded uniformly. It fixes what is asked, and is used after the units to be studied are already decided.

• Scaling — a measurement procedure: it assigns numbers or ordered categories to attitudes, opinions or traits so that qualitative responses become quantitatively comparable.

• Primary — a qualifier for the origin of material: primary data are gathered first-hand by the investigator from the original source, as against secondary data taken from existing records.

Only sampling names a selection step, and that is the process the stem defines.