方法对比

	在线便利抽样	目的性抽样	配额抽样
领域	调查方法论	调查方法论	调查方法论
方法族	Process / pipeline	Process / pipeline	Process / pipeline
起源年份	1990s–2000s (internet survey era)	Formalized ~1980–1990	1930s
提出者	Evolved from convenience sampling; internet applications documented from mid-1990s onward	Michael Quinn Patton (systematic articulation); roots in early qualitative inquiry	Developed in market research and opinion polling, notably applied by George Gallup in the 1930s
类型	Non-probability sampling	Non-probability sampling strategy	Non-probability sampling design
开创性文献	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	Moser, C. A., & Kalton, G. (1972). Survey Methods in Social Investigation (2nd ed.). Heinemann. ISBN: 978-0435827496
别名	web-based convenience sampling, internet convenience sampling, digital convenience sampling, online accidental sampling	judgmental sampling, selective sampling, criterion-based sampling, purposeful sampling	quota-controlled sampling, quota selection, non-probability quota sampling
相关	3	4	5
摘要	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.	Quota sampling is a non-probability technique in which the researcher pre-specifies how many units to recruit from each subgroup (quota cell) defined by one or more control variables such as age, gender, or occupation. Interviewers or data collectors then use their own judgment to find and enroll participants until each cell is filled. The method guarantees the sample mirrors the population on the control variables but does not provide the randomness needed for classical statistical inference.