1. Brain Team, Google Research, The Netherlands. E-mail: marcvanzee@google.com
2. Department of Information and Computing Sciences, Utrecht University, The Netherlands
3. Department of Law, Technology, Markets and Society, Tilburg University, The Netherlands. E-mail: F.J.Bex@uu.nl
4. School of Computing and Information Science (SCIS), University of Maine, ME, USA. E-mail: sepideh.ghanavati@maine.edu