Which term refers to data collection from a subset of the population to infer population characteristics?

• A. Observational study
• B. Case study
• C. Sample survey
• D. Cross-sectional study

Answer: (C)

The idea being tested is making inferences about a whole population from information gathered on a smaller group. A sample survey is exactly that: you select a subset of the population, collect data from it, and use what you learn to estimate characteristics of the entire population.

An observational study involves watching or recording data without applying any intervention; a case study looks in depth at a single unit or a small number of units; a cross-sectional study collects data at one point in time, which can be from a population or a sample but doesn’t by itself emphasize inferring population characteristics from a sampled subset. The emphasis on using a subset to make population-level conclusions is what makes a sample survey the best fit.