So sánh phương pháp

	Lấy mẫu biến thiên tối đa dựa trên thực địa	Chọn mẫu cụm dựa trên thực địa
Lĩnh vực	Phương pháp luận khảo sát	Phương pháp luận khảo sát
Họ	Process / pipeline	Process / pipeline
Năm ra đời	1990 (Patton); field application established through ecological and ethnographic practice in the 1990s–2000s	1950s (theory); 1970s–1980s (field survey practice)
Người khởi xướng	Michael Quinn Patton (maximum variation sampling); adapted for field research contexts	William G. Cochran (theoretical foundations); WHO EPI programme (field application)
Loại	Purposive qualitative/mixed-methods sampling strategy	Probability sampling design
Công trình gốc	Patton, M. Q. (2002). Qualitative Research and Evaluation Methods (3rd ed.). Sage. [Maximum variation sampling discussed in Chapter 5] ISBN: 978-0761919711	World Health Organization. (1991). Training for mid-level managers: The EPI coverage survey. WHO/EPI/MLM/91.10. World Health Organization.
Tên gọi khác	field MVS, field-based purposeful maximum variation, maximum heterogeneity field sampling, diverse case field sampling	field cluster sampling, in-field cluster sampling, area cluster sampling (field), field survey cluster design
Liên quan	6	6
Tóm tắt	Field-based maximum variation sampling is a purposive strategy in which a researcher deliberately selects field sites, ecological plots, communities, or observational units that span the widest possible range of relevant characteristics. By maximising heterogeneity among selected units, the approach ensures that both common patterns shared across diverse conditions and unique features specific to particular contexts are documented, making findings robust across a broad spectrum of real-world variation.	Field-based cluster sampling is a probability sampling method in which naturally occurring geographic or administrative groups (clusters) are first randomly selected, and then data are collected in person from units within those clusters. It is the standard design for large-scale field surveys in public health, agriculture, education, and humanitarian response, where compiling a full population list is impractical but clusters such as villages, schools, or census tracts can be identified and physically accessed.