手法を比較

	粗化完全マッチング（CEM）	差分の差 (Difference-in-Differences, DiD)
分野	因果推論	計量経済学
系統	Regression model	Regression model
提唱年	2011-2012	1994
提唱者	Iacus, King, & Porro	Card & Krueger (canonical 1994 application); Angrist & Pischke (textbook treatment)
種類	Matching / causal inference	Causal inference / panel regression
原典	Iacus, S. M., King, G., & Porro, G. (2012). Causal Inference without Balance Checking: Coarsened Exact Matching. Political Analysis, 20(1), 1-24.	Angrist, J. D., & Pischke, J.-S. (2009). Mostly Harmless Econometrics: An Empiricist's Companion. Princeton University Press. ISBN: 978-0691120355
別名	CEM, coarsened matching, monotonic imbalance bounding matching	diff-in-diff, DiD, Farkların Farkı (Diff-in-Diff)
関連	6	5
概要	Coarsened Exact Matching is a preprocessing method that achieves covariate balance by temporarily coarsening continuous variables into bins, exactly matching treated and control units within those bins, and then discarding all unmatched units. Introduced by Iacus, King, and Porro (2011, 2012), it bounds imbalance on each covariate independently, yielding a matched sample on which any estimator can be applied without relying on a propensity score model.	Difference-in-Differences is a causal-inference method that estimates the effect of an intervention by comparing how a treatment group and a control group change over time. Made famous by Card and Krueger's 1994 minimum-wage study and developed in Angrist and Pischke's Mostly Harmless Econometrics, it isolates the treatment effect as the difference between the two groups' before-after changes.