Vertaile menetelmiä

	Kenttäpohjainen lumipallo-otanta	Lumipallo-otanta
Tieteenala	Kyselytutkimuksen metodologia	Kyselytutkimuksen metodologia
Menetelmäperhe	Process / pipeline	Process / pipeline
Syntyvuosi	1961 (foundational); field variant developed through 1970s–1980s ethnographic and hidden population research	1961
Kehittäjä	Leo A. Goodman (snowball sampling); field adaptation through ethnographic and social network research traditions	Leo A. Goodman
Tyyppi	Non-probability sampling technique	Non-probability sampling technique
Alkuperäislähde	Goodman, L. A. (1961). Snowball sampling. Annals of Mathematical Statistics, 32(1), 148–170.	Goodman, L. A. (1961). Snowball sampling. Annals of Mathematical Statistics, 32(1), 148–170.
Rinnakkaisnimet	in-person snowball sampling, fieldwork chain-referral sampling, field snowball sampling, face-to-face referral sampling	chain-referral sampling, network sampling, respondent-driven sampling, referral sampling
Liittyvät	3	3
Tiivistelmä	Field-based snowball sampling is a non-probability chain-referral technique in which an initial set of in-person contacts (seeds) recruit further participants from within their real-world social networks, expanding the sample iteratively through face-to-face interaction in naturalistic field settings. It is the default snowball approach in ethnographic and community fieldwork, and is particularly valuable when the target population is hidden, hard-to-reach, or lacks a sampling frame.	Snowball sampling is a non-probability recruitment technique in which initial participants (seeds) refer the researcher to others who meet the study criteria, and those referrals in turn refer further participants. The sample grows incrementally — like a rolling snowball — until the required size or theoretical saturation is reached. It is the method of choice when a target population has no accessible sampling frame, such as undocumented migrants, illicit drug users, survivors of stigmatised experiences, or members of closed professional networks.