Maximum Agreement Subtree (of 3 or More Trees)

TLDR: The maximum agreement subtree problem for k trees (k-MAST) as mentioned in this paper is a generalization of a similar problem for two trees (MAST), where a tuple of k rooted leaf-labeled trees (T1, T2 : : : Tk) is considered.

Abstract: The maximum agreement subtree problem for k trees (k-MAST) is a generalization of a similar problem for two trees (MAST). Consider a tuple of k rooted leaf-labeled trees (T1; T2 : : : Tk). Let A D fa1; a2; : : : ang be the set of leaf labels. Any subset B A uniquely determines the socalled topological restriction T jB of the three T to B . Namely, T jB is the topological subtree of T spanned by all leaves labeled with elements from B and the lowest common ancestors of all pairs of these leaves. In particular, the ancestor relation in T jB is defined so that it agrees with the ancestor relation in T . A subset B of A such T 1 jB; : : : ; T k jB are isomorphic is called an agreement set.