The impact of public employment : evidence from Bonn / Sascha O. Becker (University of Warwick, CAGE, CEPR and IZA), Stephan Heblich (University of Bristol, IZA and SERC), Daniel M. Sturm (London School of Economics and CEPR) ; IZA Institute of Labor Economics. Bonn, Germany : IZA Institute of Labor Economics, January 2018