A general ordertheoretic linear programming model fur the study of matroid-
type greedy algorithms is introduced. The primal restrictions are given by
so-called weakly increasing submodular functions on antichains. The LP-dual
is solved by a Monge-type greedy algorithm. The model offers a direct comb
inatorial explanation for many integrality results in discrete optimization
. In particular, the submodular intersection theorem of Edmonds and Giles i
s seen to extend to the ease with a rooted forest as underlying structure.
The core of associated polyhedra is introduced and applications to the exis
tence of the core in cooperative game theory are discussed.