مقایسهٔ روش‌ها

	نمونه‌گیری در دسترس آنلاین	نمونه‌گیری هدفمند
حوزه	روش‌شناسی پیمایش	روش‌شناسی پیمایش
خانواده	Process / pipeline	Process / pipeline
سال پیدایش	1990s–2000s (internet survey era)	Formalized ~1980–1990
پدیدآور	Evolved from convenience sampling; internet applications documented from mid-1990s onward	Michael Quinn Patton (systematic articulation); roots in early qualitative inquiry
نوع	Non-probability sampling	Non-probability sampling strategy
منبع بنیادین	Gosling, S. D., Vazire, S., Srivastava, S., & John, O. P. (2004). Should we trust web-based studies? A comparative analysis of six preconceptions about internet questionnaires. American Psychologist, 59(2), 93–104.	Patton, M. Q. (1990). Qualitative Evaluation and Research Methods (2nd ed.). Sage. ISBN: 978-0803937796
نام‌های دیگر	web-based convenience sampling, internet convenience sampling, digital convenience sampling, online accidental sampling	judgmental sampling, selective sampling, criterion-based sampling, purposeful sampling
مرتبط	3	4
خلاصه	Online convenience sampling is a non-probability technique in which participants are recruited via internet channels — survey platforms, social media, email lists, or research panels — simply because they are accessible and willing to respond. It is the online analogue of traditional convenience sampling, offering fast, low-cost data collection at the expense of known representativeness. It is among the most widely used approaches in social, behavioral, and health sciences research conducted through web-based surveys.	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.