1. Department of Business and Economics, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark, and IZA (e-mail: )
2. Department of Business and Economics, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark and IZA (e-mail: )
3. Faculty of Law and Economics, Johannes Gutenberg-University Mainz, Jacob-Weider-Weg 4, 55128 Mainz, Germany and VU University Amsterdam (e-mail: )