مقایسهٔ روش‌ها

	نمونه‌گیری آزمایشی موردی انحرافی	نمونه‌گیری موارد انحرافی
حوزه	روش‌شناسی پیمایش	روش‌شناسی پیمایش
خانواده	Process / pipeline	Process / pipeline
سال پیدایش	2002 (Patton codification); pilot study tradition mid-20th century	1990
پدیدآور	Patton (deviant case sampling); pilot study methodology attributed broadly to pre-main-study practice traditions	Michael Quinn Patton
نوع	Purposive sampling variant applied in pilot phase	Purposive qualitative sampling strategy
منبع بنیادین	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
نام‌های دیگر	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
مرتبط	2	5
خلاصه	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.