Article révisé par les pairs
Résumé : In recent years, there has been an increased literature onso-called generalized network design problems (GNDPs),such as the generalized minimum spanning tree problemand the generalized traveling salesman problem. Ina GNDP, the node set of a graph is partitioned into “clusters,”and the feasible solutions must contain one nodefrom each cluster. Up to now, the polyhedra associatedwith different GNDPs have been studied independently.The purpose of this article is to show that it is possible,to a certain extent, to derive polyhedral resultsfor all GNDPs simultaneously. Along the way, we pointout some interesting connections to other polyhedra,such as the quadratic semiassignment polytope and theboolean quadric polytope.