So sánh phương pháp

	Lấy mẫu có trọng số trực tuyến	Trọng số điểm xu hướng (PSW / IPW)
Lĩnh vực	Phương pháp luận khảo sát	Suy luận nhân quả
Họ	Process / pipeline	Regression model
Năm ra đời	Late 1990s–2000s	1983 (propensity score); 2003 (efficient IPW estimator)
Người khởi xướng	Survey methodology practitioners; systematized via probability-based online panels (e.g., Knowledge Networks, founded late 1990s)	Rosenbaum & Rubin (propensity score); Hirano, Imbens & Ridder (efficient weighting)
Loại	Probability-adjusted online sampling technique	Causal inference / reweighting
Công trình gốc	Dillman, D. A., Smyth, J. D., & Christian, L. M. (2014). Internet, Phone, Mail, and Mixed-Mode Surveys: The Tailored Design Method (4th ed.). Wiley. ISBN: 978-1118456149	Rosenbaum, P. R., & Rubin, D. B. (1983). The central role of the propensity score in observational studies for causal effects. Biometrika, 70(1), 41-55.
Tên gọi khác	web-based weighted sampling, internet survey weighting, online panel weighting, weighted internet sampling	PSW, inverse probability weighting, IPW, propensity-based weighting
Liên quan	4	6
Tóm tắt	Online weighted sampling is the practice of recruiting respondents via internet platforms and then applying statistical weights to correct for unequal selection probabilities, coverage gaps, and differential non-response. It enables researchers to draw valid population inferences from web surveys by compensating for the structural biases inherent in online recruitment — including the fact that not all members of a target population have equal internet access or equal likelihood of joining a panel.	Propensity score weighting is a causal-inference method that reweights observations so that the covariate distributions of treated and untreated units look exchangeable, enabling unbiased estimation of average treatment effects from observational data. Each unit receives a weight that is the inverse of its probability of receiving the treatment it actually received — a strategy formalised by Rosenbaum and Rubin (1983) and given its efficient semiparametric form by Hirano, Imbens and Ridder (2003).