Encyclopedia of Law and Economics

2019 Edition
| Editors: Alain Marciano, Giovanni Battista Ramello


  • J. L. JiménezEmail author
  • J. Perdiguero
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-7753-2_664


The difference-in-difference (DiD) is one of the most popular approaches to evaluate causal effects of programs or policies. The idea is very simple: a treatment group is affected by an external change in one period, and the main aim is to evaluate how this treated group changes after the policy, regarding a control group that is not affected. So it controls the double difference (changes over time and over control group). Although some assumptions have to be assumed, its flexibility and requiring a relatively small volume of data yield to a large number of papers and documents that use it on topics as competition policy, merger evaluations, political economy, and so on.

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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Facultad de Economía, Empresa y Turismo, Departamento de Análisis Económico Aplicado. Despacho D.2-12Universidad de Las Palmas de Gran CanariaLas Palmas de Gran CanariaSpain
  2. 2.Departament d’Economia Aplicada, Research Group of “Economia Aplicada” (GEAP)Universitat Autònoma de BarcelonaBellaterraSpain