So sánh phương pháp

	Lấy mẫu lý thuyết trực tuyến	Lấy mẫu chuỗi giới thiệu – Lấy mẫu quả cầu tuyết
Lĩnh vực	Phương pháp luận khảo sát	Phương pháp luận khảo sát
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1967 (theoretical sampling); online adaptation ~2000s–2010s	1961
Người khởi xướng	Glaser & Strauss (theoretical sampling); adapted to online contexts by internet qualitative researchers	Leo A. Goodman
Loại	Qualitative sampling strategy	Non-probability sampling technique
Công trình gốc	Glaser, B. G., & Strauss, A. L. (1967). The Discovery of Grounded Theory: Strategies for Qualitative Research. Aldine. ISBN: 978-0202302607	Goodman, L. A. (1961). Snowball sampling. Annals of Mathematical Statistics, 32(1), 148–170.
Tên gọi khác	internet-based theoretical sampling, digital theoretical sampling, web-based theoretical sampling	chain-referral sampling, network sampling, respondent-driven sampling, referral sampling
Liên quan	4	3
Tóm tắt	Online theoretical sampling applies the logic of theoretical sampling — selecting participants or data sources based on emerging theory rather than predetermined criteria — within digital environments. Researchers iteratively recruit from online communities, forums, social media, or virtual networks, guided at each step by conceptual gaps identified during concurrent analysis. It is most commonly used in grounded theory studies conducted wholly or partially over the internet.	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.