1. CPB Netherlands Bureau for Economic Policy Analysis, 2594 AV The Hague, Netherlands
2. Ivey Business School, Western University, London, Ontario N6G 0N1, Canada; and Centre for Economic Policy Research, London EC1V 0DX, United Kingdom
3. Department of Innovation and Organizational Economics, Copenhagen Business School, 2000 Frederiksberg, Denmark; IZA–Institute of Labor Economics, 53113 Bonn, Germany; Centre for Economic Policy Research, London EC1V 0DX, United Kingdom; and Tinbergen Institute, 3062 PA Rotterdam, Netherlands