เปรียบเทียบวิธี

	การสุ่มตัวอย่างกรณีเบี่ยงเบนนำร่อง	การเลือกตัวอย่างกรณีที่เบี่ยงเบน
สาขาวิชา	ระเบียบวิธีสำรวจ	ระเบียบวิธีสำรวจ
ตระกูล	Process / pipeline	Process / pipeline
ปีกำเนิด	2002 (Patton codification); pilot study tradition mid-20th century	1990
ผู้ริเริ่ม	Patton (deviant case sampling); pilot study methodology attributed broadly to pre-main-study practice traditions	Michael Quinn Patton
ประเภท	Purposive sampling variant applied in pilot phase	Purposive qualitative sampling strategy
แหล่งต้นตำรับ	Patton, M. Q. (2002). Qualitative Research and Evaluation Methods (3rd ed.). Sage. [Chapter 5: Sampling Strategies, pp. 230–246 on deviant/extreme case sampling] ISBN: 978-0761919711	Patton, M. Q. (2002). Qualitative Research and Evaluation Methods (3rd ed.). Sage Publications. ISBN: 978-0761919711
ชื่อเรียกอื่น	pilot extreme case sampling, pilot outlier sampling, pilot atypical case sampling, pilot deviant-case pilot sampling	extreme case sampling, outlier sampling, negative case sampling, deviant-case selection
ที่เกี่ยวข้อง	2	5
สรุป	Pilot deviant case sampling is a purposive sampling strategy applied during a pilot phase in which participants are deliberately selected because they represent extreme, unusual, or atypical instances of the phenomenon under study. Rather than seeking representative participants for the pilot run, the researcher intentionally recruits outlier cases to probe the boundaries of research instruments, interview guides, or data collection protocols before the main study begins.	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.