An efficient bottom-up distance between trees

Abstract

A new bottom-up distance measure for labeled trees, which is based on the largest common forest of the trees and has the threefold advantage of independence ofparticular edit costs, low complexity, and coverage of ordered and unordered trees, is introduced and related in this paper with other distance measures published in the literature. Algorithms for computing the bottom-up distance in time linear in the number ofnodes are given in full detail.