1. Department of Computer Science, Universitat Oberta de Catalunya, 08018 Barcelona, Spain
2. Smurfit Business School, University College Dublin, Blackrock, D04 V1W8 Dublin, Ireland
3. Department of Telecommunication and Systems Engineering, Universitat Autònoma de Barcelona, 08202 Sabadell, Spain
4. Department of Management, Universitat Politècnica de Catalunya, 08028 Barcelona, Spain
5. Department of Management, Euncet Business School, 08225 Terrassa, Spain
6. Department of Applied Statistics and Operations Research, Universitat Politècnica de València, 03801 Alcoy, Spain