# Composed Bisimulation for Tree Automata

@article{Abdulla2009ComposedBF,
title={Composed Bisimulation for Tree Automata},
author={Parosh Aziz Abdulla and Ahmed Bouajjani and Luk{\'a}{\vs} Hol{\'i}k and Lisa Kaati and Tom{\'a}{\vs} Vojnar},
journal={Int. J. Found. Comput. Sci.},
year={2009},
volume={20},
pages={685-700}
}
• Published 21 July 2008
• Computer Science
• Int. J. Found. Comput. Sci.
We address the problem of reducing the size of (nondeterministic, bottom-up) tree automata using suitable, language-preserving equivalences on the states of the automata. In particular, we propose the so-called composed bisimulationas a new language preserving equivalence. Composed bisimulation is defined in terms of two different relations, namely upward and downward bisimulation. Moreover, we provide simple and efficient algorithms for computing composed bisimulation based on a reduction to…

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