Affiliation: | a Service de l’enseignement des méthodes quantitatives de gestion, HEC Montréal 3000, chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 2A7 b Department of Statistical and Actuarial Sciences, University of Western Ontario, 1151 Richmond St., London, ON, Canada N6A 5B7 |