1. Toulouse School of Economics, Centre National de la Recherche Scientifique, University of Toulouse Capitole, Toulouse 31042, France;
2. Centre for Economic Policy Research, London EC1V 0DX, United Kingdom;
3. Center for Economic Studies, Munich 81679, Germany;
4. Department of Econometrics and Operations Research, Tilburg University, 5037 AB Tilburg, Netherlands;
5. Karlsruhe Institute of Technology, ECON Institute, Karlsruhe 76049, Germany;
6. Berlin Social Science Center, 10785 Berlin, Germany;
7. Institute for Microeconomics, University of Bonn, Bonn 53113, Germany