GenerativeModel is pairwise disjoint with DiscriminativeModel and DFModel. But DiscriminativeModel and DiscriminantFunctionModel may or may not be disjoint because some DF models output probabilities. Those who argue for disjointness say that even if DF models output probabilities, what distinguished them from discriminative models is their ModelStructure. If this is not a posterior probability distribution as in logistic regession, then the model is a DFmodel. A potential counter-argument is that maybe it is the concept of ModelStructure that needs to be revised. The issue remains open.