So sánh phương pháp

	Lấy mẫu lý thuyết trực tuyến	Chọn mẫu có chủ đích
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	Formalized ~1980–1990
Người khởi xướng	Glaser & Strauss (theoretical sampling); adapted to online contexts by internet qualitative researchers	Michael Quinn Patton (systematic articulation); roots in early qualitative inquiry
Loại	Qualitative sampling strategy	Non-probability sampling strategy
Công trình gốc	Glaser, B. G., & Strauss, A. L. (1967). The Discovery of Grounded Theory: Strategies for Qualitative Research. Aldine. ISBN: 978-0202302607	Patton, M. Q. (1990). Qualitative Evaluation and Research Methods (2nd ed.). Sage. ISBN: 978-0803937796
Tên gọi khác	internet-based theoretical sampling, digital theoretical sampling, web-based theoretical sampling	judgmental sampling, selective sampling, criterion-based sampling, purposeful sampling
Liên quan	4	4
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.	Purposive sampling is a non-probability strategy in which the researcher deliberately selects participants, documents, or cases that are information-rich with respect to the research question. Rather than drawing units at random, the researcher applies explicit criteria aligned with the study's purpose, maximising the depth and relevance of the data collected. It is the default sampling logic in most qualitative research designs and is also used in mixed-methods and applied evaluative work.