Define sampling and name two sampling methods commonly used in educational research.

• A. Process of selecting a subset of a population; simple random sampling and stratified sampling.
• B. Process of testing every individual.
• C. Process of including volunteers only.
• D. Process of collecting data from non-representative samples.

Answer: (A)

Sampling is the process of selecting a subset of individuals from a larger population so you can study them and make inferences about the whole group without surveying everyone. In educational research, two common probability methods are simple random sampling and stratified sampling. Simple random sampling means every person in the population has an equal chance of being chosen, which helps minimize bias. Stratified sampling involves dividing the population into meaningful subgroups (like grade levels, schools, or regions) and sampling from each subgroup, so the sample reflects the structure of the population and captures variation across important subgroups.

Other options miss the defining idea. Testing every individual describes a census, not sampling. Including volunteers only relies on who volunteers, which can introduce bias and isn’t guaranteed to represent the whole population. Collecting data from non-representative samples highlights a problem with the sample, not a recognized sampling method.