手法を比較

	Staggered Difference-in-Differences	合成対照法（SCM）
分野	因果推論	因果推論
系統	Regression model	Regression model
提唱年	2021	2010
提唱者	Callaway & Sant'Anna; Sun & Abraham	Abadie, Diamond & Hainmueller
種類	Quasi-experimental panel causal estimator	Counterfactual causal-inference model
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	staggered DID, staggered adoption DID, heterogeneous treatment DID, Callaway-Sant'Anna estimator	synthetic control method, SCM, synthetic counterfactual, Sentetik Kontrol Yöntemi (SCM)
関連	4	5
概要	Staggered Difference-in-Differences is a generalisation of DID for panel designs in which treatment is rolled out to different groups at different times. Introduced in the modern form by Callaway and Sant'Anna (2021) and Sun and Abraham (2021), it corrects the bias that classical two-way fixed-effects (TWFE) estimators suffer when treatment effects are heterogeneous across cohorts and over time.	The Synthetic Control Method, introduced by Abadie, Diamond and Hainmueller in 2010, builds a weighted counterfactual for a single treated unit from a pool of untreated donor units. It is widely regarded as the gold standard for evaluating large policy interventions, natural experiments, and N=1 case studies where no obvious comparison unit exists.