เปรียบเทียบวิธี

	การเลือกตัวอย่างแบบปรับเปลี่ยนตามวัตถุประสงค์	การเลือกตัวอย่างกรณีที่เบี่ยงเบน
สาขาวิชา	ระเบียบวิธีสำรวจ	ระเบียบวิธีสำรวจ
ตระกูล	Process / pipeline	Process / pipeline
ปีกำเนิด	1980s–1990s	1990
ผู้ริเริ่ม	Rooted in Patton's purposive sampling typology; adaptive dimension from iterative qualitative inquiry traditions	Michael Quinn Patton
ประเภท	Qualitative sampling strategy	Purposive qualitative sampling strategy
แหล่งต้นตำรับ	Patton, M. Q. (2002). Qualitative Research and Evaluation Methods (3rd ed.). Sage Publications. ISBN: 978-0761919711	Patton, M. Q. (2002). Qualitative Research and Evaluation Methods (3rd ed.). Sage Publications. ISBN: 978-0761919711
ชื่อเรียกอื่น	iterative purposive sampling, emergent purposive sampling, adaptive qualitative sampling, dynamic purposive sampling	extreme case sampling, outlier sampling, negative case sampling, deviant-case selection
ที่เกี่ยวข้อง	5	5
สรุป	Adaptive purposive sampling is a qualitative strategy in which the researcher begins with explicitly stated, theory-driven selection criteria and then deliberately revises those criteria as data collection proceeds and new understanding emerges. Unlike fixed purposive sampling — where criteria are locked in before fieldwork — the adaptive variant treats the sampling frame as a working hypothesis that is refined in response to early findings, enabling the study to follow the evidence into unexpected but analytically important directions.	Deviant case sampling is a purposive qualitative sampling strategy in which the researcher intentionally selects cases that are unusual, exceptional, or markedly different from the norm — outliers, extreme successes, or conspicuous failures. The goal is not statistical representation but deep learning from cases that illuminate the boundaries of a phenomenon, challenge prevailing assumptions, or reveal processes that typical cases obscure.