A generalization of antiwebs to independence systems and canonical facets

The paper considers independence system polytopes, i.e. polytopes whose extreme points are the incidence vectors of the sets of an independence system. It first gives a sufficient condition for recognizing Boolean facets. Then, the notion of antiweb introduced by Trotter for graphs is generalized to independence systems and used for obtaining canonical facets of the associated polytopes. The paper also point out how our results relate with known ones for knapsack, set covering and matroid polytopes.