The New Palgrave Dictionary of Economics

2018 Edition
| Editors: Macmillan Publishers Ltd

Difference-in-Difference Estimators

  • Alberto Abadie
Reference work entry


This article discusses difference-in-differences (DID) estimators, which are commonly applied in evaluation research. In particular, the discussion focuses on (a) motivation, definition and interpretation of DID estimators, (b) conditions under which DID estimators are valid, (c) data requirements to compute DID estimators, (d) representative applications of DID estimators in the empirical economics literature, (e) extensions of DID estimators, and (f) a simple indirect test to assess the validity of these estimators.


Difference-in-differences estimators Evaluation studies Fixed effects Minimum wages 

JEL Classifications

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Copyright information

© Macmillan Publishers Ltd. 2018

Authors and Affiliations

  • Alberto Abadie
    • 1
  1. 1.