手法を比較

	パネルデータ操作変数テスト（Panel Data Placebo Test）	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	2004-2010	1994
提唱者	Bertrand, Duflo & Mullainathan; Abadie, Diamond & Hainmueller	Card & Krueger (canonical 1994 application); Angrist & Pischke (textbook treatment)
種類	Falsification / validation test	Causal inference / panel regression
原典	Bertrand, M., Duflo, E., & Mullainathan, S. (2004). How Much Should We Trust Differences-in-Differences Estimates? Quarterly Journal of Economics, 119(1), 249-275.	Angrist, J. D., & Pischke, J.-S. (2009). Mostly Harmless Econometrics: An Empiricist's Companion. Princeton University Press. ISBN: 978-0691120355
別名	placebo regression test, falsification test, pseudo-treatment test, in-time placebo	diff-in-diff, DiD, Farkların Farkı (Diff-in-Diff)
関連	4	5
概要	A panel data placebo test is a falsification procedure used to assess the credibility of causal estimates in quasi-experimental panel designs. By applying the same estimation strategy to a period, group, or outcome where no true effect should exist, researchers verify that the observed treatment effect is not merely an artifact of model specification, coincidental trends, or data patterns unrelated to the intervention.	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.