Difference-in-differences

Denis Fougère (1, 2, 3, 4, 5) , Nicolas Jacquemet (6, 7)

1 OSC - Observatoire sociologique du changement (Sciences Po, CNRS)
2 CNRS - Centre National de la Recherche Scientifique
3 LIEPP - Laboratoire interdisciplinaire d'évaluation des politiques publiques (Sciences Po)
4 CEPR - Center for Economic Policy Research
5 IZA - Forschungsinstitut zur Zukunft der Arbeit - Institute of Labor Economics
6 PSE - Paris School of Economics
7 CES - Centre d'économie de la Sorbonne

The difference-in-differences method is a quantitative, quasi-experimental method to assess the impact of an intervention by setting up comparison groups and measuring the change in an outcome between a pre- and a post-intervention period when only one of the two groups has access to the intervention. This method is very useful for ex-post impact evaluation.

Mots clés: Quantitative methods; Quasi-experimental methods; difference-in-differences; difference-in-difference-in-differences; longitudinal data; parallel trends; Entropy balancing; synthetic/artificial control group

Domaines: Sciences de l'Homme et Société; Science politique

Denis Fougère, Nicolas Jacquemet. Difference-in-differences. LIEPP Methods Brief n°10, 2023. ⟨hal-04102943⟩