Top-down tree edit-distance of regular tree languages

Sang Ki Ko, Yo Sub Han, Kai Salomaa

Research output: Chapter in Book/Report/Conference proceedingConference contribution


We study the edit-distance of regular tree languages. The edit-distance is a metric for measuring the similarity or dissimilarity between two objects, and a regular tree language is a set of trees accepted by a finite-state tree automaton or described by a regular tree grammar. Given two regular tree languages L and R, we define the edit-distance d(L,R) between L and R to be the minimum edit-distance between a tree t1 ∈ L and t2 ∈ R, respectively. Based on tree automata for L and R, we present a polynomial algorithm that computes d(L,R). We also suggest how to use the edit-distance between two tree languages for identifying a special common string between two context-free grammars.

Original languageEnglish
Title of host publicationLanguage and Automata Theory and Applications - 8th International Conference, LATA 2014, Proceedings
Number of pages12
Publication statusPublished - 2014
Event8th International Conference on Language and Automata Theory and Applications, LATA 2014 - Madrid, Spain
Duration: 2014 Mar 102014 Mar 14

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume8370 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Other8th International Conference on Language and Automata Theory and Applications, LATA 2014

Bibliographical note

Funding Information:
Ko and Han were supported by the Basic Science Research Program through NRF funded by MEST (2012R1A1A2044562), and Salomaa was supported by the Natural Sciences and Engineering Research Council of Canada Grant OGP0147224.

All Science Journal Classification (ASJC) codes

  • Theoretical Computer Science
  • Computer Science(all)


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