1. Department of Economics, Center for Research and Teaching in Economics (CIDE), Aguascalientes, Mexico
2. Program for Longitudinal Studies, Experiments and Surveys, Center for Research and Teaching in Economics (CIDE), Aguascalientes, Mexico
3. Center for Research in Geospacial Information Science (CentroGeo), Aguascalientes, Mexico
4. Mexican National Council for Science and Technology (CONACYT), Mexico
5. University of Monterrey, Mexico
6. Institute for the Study of Labor, Germany