手法を比較

	異質的処置効果差の差 (HTE-DiD)	合成コントロール法（SCM）
分野	因果推論	因果推論
系統	Regression model	Regression model
提唱年	2021	2003–2010
提唱者	Callaway & Sant'Anna; Sun & Abraham	Alberto Abadie & Javier Gardeazabal (2003); Abadie, Diamond & Hainmueller (2010)
種類	Causal inference / panel regression	Quasi-experimental causal inference
原典	Callaway, B., & Sant'Anna, P. H. C. (2021). Difference-in-Differences with multiple time periods. Journal of Econometrics, 225(2), 200-230.	Abadie, A., Diamond, A., & Hainmueller, J. (2010). Synthetic Control Methods for Comparative Case Studies: Estimating the Effect of California's Tobacco Control Program. Journal of the American Statistical Association, 105(490), 493-505.
別名	HTE-DiD, heterogeneous DiD, CATT estimator, group-time ATT	SCM, synthetic control, synth estimator, Abadie-Diamond-Hainmueller method
関連	4	4
概要	HTE-DiD extends the classic Difference-in-Differences estimator to settings where treatment effects vary across units, time periods, or treatment cohorts. Developed formally by Callaway and Sant'Anna (2021) and Sun and Abraham (2021), it avoids the biases that arise when a conventional two-way fixed-effects regression is used with staggered adoption or effect heterogeneity, by estimating cohort-and-time-specific average treatment effects that can then be aggregated flexibly.	The Synthetic Control Method estimates the causal effect of a treatment or policy on a single treated unit by constructing a weighted combination of untreated units — the synthetic control — that closely resembles the treated unit before the intervention. The gap between the treated unit and its synthetic counterpart after the intervention is the estimated treatment effect.