Modeling the effects of grade retention in high school / Stijn Baert (Sherppa, Ghent university, university of Antwerp, université catholique de Louvain and IZA), Bart Cockx (Sherppa, Ghent university, IRES, université catholique de Louvain, CESifo and IZA), Matteo Picchio (Marche polytechnic university, CentER, Tilburg university, Sherppa, Ghent university and IZA). Bonn : IZA, 2015