2 IZA Discussion Papers
IZA Discussion Paper No. 13667
forthcoming in: Data Science for Entrepreneurship, edited by W.J. Liebregts, W.J.A.M. van den Heuvel and J.A. van den Born, to be published by Springer.
IZA Discussion Paper No. 6341
revised version published in: World Development, 2013, 41, 265–285