手法を比較

	傾向スコア重み付け（PSW / IPW）	逆確率重み付け法 (IPW / IPTW)
分野	因果推論	因果推論
系統	Regression model	Regression model
提唱年	1983 (propensity score); 2003 (efficient IPW estimator)	2000
提唱者	Rosenbaum & Rubin (propensity score); Hirano, Imbens & Ridder (efficient weighting)	Robins, Hernán & Brumback
種類	Causal inference / reweighting	Causal inference weighting estimator
原典	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.	Robins, J. M., Hernán, M. A., & Brumback, B. (2000). Marginal Structural Models and Causal Inference in Epidemiology. Epidemiology, 11(5), 550-560.
別名	PSW, inverse probability weighting, IPW, propensity-based weighting	IPW, IPTW, inverse probability of treatment weighting, marginal structural model weighting
関連	6	5
概要	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).	Inverse Probability Weighting is a causal-inference method that assigns each observation a weight equal to the inverse of its probability of receiving the treatment it actually received. Introduced by Robins, Hernán and Brumback (2000) for marginal structural models, it builds a pseudo-population in which treatment is independent of measured confounders, balancing selection bias.