Computing the Rooted Triplet Distance between Galled Trees by Counting Triangles

  • Jesper Jansson
  • Andrzej Lingas
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7354)


We consider a generalization of the rooted triplet distance between two phylogenetic trees to two phylogenetic networks. We show that if each of the two given phylogenetic networks is a so-called galled tree with n leaves then the rooted triplet distance can be computed in o(n 2.688) time. Our upper bound is obtained by reducing the problem of computing the rooted triplet distance to that of counting monochromatic and almost- monochromatic triangles in an undirected, edge-colored graph. To count different types of colored triangles in a graph efficiently, we extend an existing technique based on matrix multiplication and obtain several new related results that may be of independent interest.


Matrix Multiplication Undirected Graph Phylogenetic Network Auxiliary Graph Lower Common Ancestor 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Jesper Jansson
    • 1
  • Andrzej Lingas
    • 2
  1. 1.Laboratory of Mathematical Bioinformatics, Institute for Chemical ResearchKyoto UniversityUjiJapan
  2. 2.Department of Computer ScienceLund UniversityLundSweden

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