Friendships and Favouritism on the Schoolground – A Framed Field Experiment


  • Corresponding author: Jeroen van de Ven, Department of Economics, University of Amsterdam, ACLE, Roetersstraat 11, 1018 WB Amsterdam, The Netherlands. Email:

  • We thank Gary Charness and Peter Kuhn, various seminar audiences, an anonymous referee and especially the Co-editor Jörn-Steffen Pischke for very useful comments, and are indebted to Iwan Barankay, John Ermisch, Sabine Kröger, Wieland Müller, Patrick Nolen, Imran Rasul, Karim Sadrieh and Nick Vriend for their suggestions on the design. We are much indebted to Paulette Poncin and all heads of school and teachers for their support. Jeroen van de Ven gratefully acknowledges support from the Netherlands Organisation for Scientific Research (NWO), grant 451-05-005.


We present experimental evidence on favouritism practices. Children compete in teams in a tournament. After the first round of a real effort task, children indicate which group member they would prefer to do the task in the second round, for the benefit of the team. Friends are much more likely to be chosen than others after controlling for performance. We also find that children who are favoured by their friend subsequently increase performance. Consequently, favouritism does not hurt efficiency. These results show the importance of observing performance ex post in order to properly evaluate the efficiency implications of favouritism.