A representative sample is essential in the

A representative sample is essential in the survey method, whose findings are generalised to a whole population.

Survey conclusions hold only if the sample mirrors the population's key characteristics.

The experimental method relies on control and random assignment more than on a representative sample.

The case study method examines one or a few units in depth, not a representative cross-section.

The clinical method focuses on individual diagnosis and treatment rather than population estimates.

Representativeness is what lets a survey's sample statistics estimate population parameters.