Carlos Vilalta, Pablo Lopez-Ramirez y Gustavo Fondevila, Profesor Investigador Titular de la División de Estudios Jurídicos del CIDE, escribieron el artículo Testing the local and spatial spillover effects of police monitored CCTV systems on crime en la revista Applied Geography.   Abstract Objectives Police-monitored CCTV systems are supposed to reduce on-the-street crime. The purpose of this study is to determine whether the MiCalle CCTV systems program in Mexico City had local and spatial spillover effects on delivery robberies. Methods When data is clustered in space and time, random effects and errors can be autocorrelated in both dimensions. To test the effectiveness of the MiCalle program on delivery robbery crime rates, a Difference-in-Differences (DID) design was specified in a maximum likelihood (ML) panel regression model with spatial lag…