1. “Carlo F Dondena” Center for Research on Social Dynamics and Department of Policy Analysis and Public Management, Università Bocconi, via Röntgen 1, I-20136 Milan, Italy
2. Department of Political and Social Sciences and RECSM, Universitat Pompeu Fabra and “Carlo F Dondena” Center for Research on Social Dynamics, Università Bocconi, Ramon Trias Fargas, 25-27; 08005 Barcelona, Spain
3. Department of Sociology and Nuffield College, University of Oxford, Manor Road, Oxford OX1 3UQ, England