Σύγκριση μεθόδων

	Στιβαροί Εκτιμητές Διαφορών-σε-Διαφορές	Διαχρονικά Δεδομένα Διαφορών σε Διαφορές (Panel DiD / TWFE)
Πεδίο	Αιτιακή Συμπερασματολογία	Αιτιακή Συμπερασματολογία
Οικογένεια	Regression model	Regression model
Έτος προέλευσης	2021-2023	1985–2004
Δημιουργός	Callaway & Sant'Anna; Sun & Abraham; Roth et al. (synthesised 2021-2023)	Ashenfelter & Card (1985); codified by Angrist & Pischke (2009); serial correlation critique by Bertrand, Duflo & Mullainathan (2004)
Τύπος	Causal inference / panel regression	Causal inference / panel regression
Θεμελιώδης πηγή	Callaway, B., & Sant'Anna, P. H. C. (2021). Difference-in-differences with multiple time periods. Journal of Econometrics, 225(2), 200-230.	Angrist, J. D., & Pischke, J.-S. (2009). Mostly Harmless Econometrics: An Empiricist's Companion. Princeton University Press. ISBN: 978-0691120355
Εναλλακτικές ονομασίες	robust DiD, heterogeneity-robust DiD, staggered DiD, disaggregated ATT DiD	Two-Way Fixed Effects DiD, TWFE, Panel DiD, Panel Diff-in-Diff
Συναφείς	5	4
Σύνοψη	Robust Difference-in-Differences is a family of modern DiD estimators designed to remain valid when treatment timing is staggered across units and treatment effects are heterogeneous over time or across groups. Classical two-way fixed-effects (TWFE) DiD can be severely biased in such settings; robust variants estimate group-time average treatment effects (ATTs) separately and then aggregate them in a theoretically sound way.	Panel Data Difference-in-Differences extends the classic two-period DiD design to settings with multiple units observed across many time periods. By absorbing unit-level fixed effects and time fixed effects simultaneously, it isolates the causal effect of a treatment or policy change while controlling for both time-invariant unit heterogeneity and common time shocks affecting all units.