So sánh phương pháp

	Lấy mẫu Hệ thống Trực tuyến	Lấy mẫu có hệ thống
Lĩnh vực	Phương pháp luận khảo sát	Phương pháp luận khảo sát
Họ	Process / pipeline	Process / pipeline
Năm ra đời	Late 1990s–2000s (web survey era)	Mid-20th century (Cochran 1953; Kish 1965)
Người khởi xướng	Adapted from classical systematic sampling (Madow & Madow, 1944) for web survey contexts	William G. Cochran; formalized in survey sampling theory
Loại	Probability sampling design	Probability sampling design
Công trình gốc	Couper, M. P. (2008). Designing Effective Web Surveys. Cambridge University Press. ISBN: 978-0521713528	Cochran, W. G. (1977). Sampling Techniques (3rd ed.). John Wiley & Sons. ISBN: 978-0471162407
Tên gọi khác	web systematic sampling, digital systematic sampling, interval sampling online, e-survey systematic sampling	interval sampling, systematic random sampling, equal-interval sampling, fixed-interval sampling
Liên quan	4	5
Tóm tắt	Online systematic sampling applies the classical every-k-th-element rule to digital survey contexts — selecting respondents from a web panel, membership database, or visitor stream at a fixed interval. It combines the operational simplicity of systematic sampling with the reach and speed of online data collection, producing a roughly representative sample without requiring complex randomisation infrastructure.	Systematic sampling is a probability sampling technique in which every k-th element is selected from an ordered list of the population after a random starting point. With population size N and desired sample size n, the sampling interval k = N/n is computed and one unit is chosen at random from the first interval; all subsequent units are selected by adding k repeatedly. The method is operationally simple, yields a spread-out sample, and often achieves lower variance than simple random sampling when the list has no harmful periodicity.