เปรียบเทียบวิธี

	การเลือกตัวอย่างกรณีทั่วไปตามภาคสนาม	การสุ่มตัวอย่างแบบเจาะจง
สาขาวิชา	ระเบียบวิธีสำรวจ	ระเบียบวิธีสำรวจ
ตระกูล	Process / pipeline	Process / pipeline
ปีกำเนิด	1980s–1990s	Formalized ~1980–1990
ผู้ริเริ่ม	Michael Quinn Patton; Miles & Huberman	Michael Quinn Patton (systematic articulation); roots in early qualitative inquiry
ประเภท	Purposive qualitative sampling strategy	Non-probability sampling strategy
แหล่งต้นตำรับ	Patton, M. Q. (2002). Qualitative Research and Evaluation Methods (3rd ed.). Sage Publications. ISBN: 978-0761919711	Patton, M. Q. (1990). Qualitative Evaluation and Research Methods (2nd ed.). Sage. ISBN: 978-0803937796
ชื่อเรียกอื่น	field typical case sampling, in-person typical case sampling, fieldwork typical case selection, on-site typical case sampling	judgmental sampling, selective sampling, criterion-based sampling, purposeful sampling
ที่เกี่ยวข้อง	5	4
สรุป	Field-based typical case sampling is a purposive qualitative strategy in which the researcher selects and studies cases that represent the ordinary, average, or most common instance of a phenomenon — and conducts data collection through direct fieldwork such as in-person observation, site visits, and face-to-face interviews. The combination ensures that findings portray what the phenomenon looks like under real-world, everyday conditions rather than through self-reports or online proxies.	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.