Võrdle meetodeid

	Kaalutud valim	Klastrite valim
Valdkond	Küsitlusmetoodika	Küsitlusmetoodika
Perekond	Process / pipeline	Process / pipeline
Tekkeaasta	1940s–1952 (formalized in large-scale government survey work and the Horvitz-Thompson estimator)	Early-to-mid 20th century; canonical treatment 1953/1977
Looja	Morris H. Hansen, William N. Hurwitz; D. G. Horvitz and D. J. Thompson (theoretical framework)	Formalized by William G. Cochran; roots in early 20th-century U.S. Census Bureau survey practice
Tüüp	Probability sampling design	Probability sampling design
Algallikas	Cochran, W. G. (1977). Sampling Techniques (3rd ed.). John Wiley & Sons. ISBN: 978-0471162407	Cochran, W. G. (1977). Sampling Techniques (3rd ed.). Wiley. ISBN: 978-0471162407
Rööpnimetused	probability proportional to size sampling, PPS sampling, unequal probability sampling, importance sampling	cluster random sampling, area sampling, one-stage cluster sampling
Seotud	6	5
Kokkuvõte	Weighted sampling is a probability-based design in which units are selected with unequal probabilities proportional to a known auxiliary measure of size or importance. Sampling weights — the inverse of inclusion probabilities — are applied during analysis so that each sampled unit correctly represents the population units it stands for. The approach underpins large-scale government, health, and social surveys where simple random sampling would be inefficient.	Cluster sampling is a probability sampling technique in which the population is divided into naturally occurring groups (clusters), a random sample of clusters is selected, and all — or a random subset of — members within each selected cluster are studied. It is especially practical when a complete population list is unavailable or when units are geographically dispersed, making individual random selection prohibitively expensive. One-stage cluster sampling surveys every member of selected clusters; two-stage designs add a second random draw within clusters.