Did the Military Interventions in the Mexican Drug War Increase Violence? Valeria Espinosa 1 and Donald B. Rubin 1 Department of Statistics, Harvard University 1 Valeria Espinosa is a PhD candidate in the Department of Statistics at Harvard University, One Oxford Street, 7th floor, Cambridge, MA (e-mail: vespinos@fas.harvard.edu); and Donald B. Rubin is the John L. Loeb Professor of Statistics at Harvard University, One Oxford Street, 7th floor, Cambridge, MA. The authors thank Miguel Basa˜ nez, Elisa de Anda, Viridiana R´ ıos, Jonathan Hennessy, Joseph Kelly, and the referees for helpful comments.