Sampling Methods in Research
Sampling is the process of selecting a subset of individuals, observations, or units (the sample) from a larger population to study. Sampling methods are broadly classified into probability (random) and non-probability (non-random) approaches. Probability methods—random sampling, stratified sampling, cluster sampling, systematic sampling—enable statistical inference to the population and allow calculation of confidence intervals and margins of error. Non-probability methods—convenience, purposive, snowball, quota sampling—are practical for exploratory or qualitative research but do not support formal statistical generalization. Cochran's Sampling Techniques (1977) and Kish's Survey Sampling (1965) are foundational references; modern applications span surveys, experiments, qualitative studies, and clinical trials.
Source record
Citations copied verbatim from the method’s source record. No claim-level verification is inferred from them.
- Cochran, W. G. (1977). Sampling Techniques (3rd ed.). John Wiley & Sons. · URL
- Kish, L. (1965). Survey Sampling. John Wiley & Sons. · URL
- Patton, M. Q. (2015). Qualitative Research & Evaluation Methods (4th ed.). SAGE Publications. · URL
Curated claims
Claims persisted in the evidence ledger, each with its own assessment.
This view does not invent a claim assessment when the ledger has none.
Related methods
Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.