Abstract
Weighted tree automata (WTA) extend classical weighted automata (WA) to the non-linear structure of trees. The expressive power of WA with varying degrees of ambiguity has been extensively studied. Unambiguous, finitely ambiguous, and polynomially ambiguous WA over the tropical (as well as the arctic) semiring strictly increase in expressive power. The recently developed pumping results of Mazowiecki and Riveros (STACS 2018) are lifted to trees in order to achieve the same strict hierarchy for WTA over the tropical (as well as the arctic) semiring.
K. Stier—Financially supported by DFG Research Training Group 1763 (QuantLA).
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Berstel, J., Reutenauer, C.: Recognizable formal power series on trees. Theoret. Comput. Sci. 18(2), 115–148 (1982)
Berstel, J., Reutenauer, C.: Rational Series and Their Languages, EATCS Monographs on Theoretical Computer Science, vol. 12. Springer, Heidelberg (1988)
Borchardt, B.: The theory of recognizable tree series. Ph.D. thesis, Technische Universität Dresden (2005)
Bozapalidis, S., Louscou-Bozapalidou, O.: The rank of a formal tree power series. Theoret. Comput. Sci. 27(1–2), 211–215 (1983)
Chattopadhyay, A., Mazowiecki, F., Muscholl, A., Riveros, C.: Pumping lemmas for weighted automata. arXiv:2001.06272 arXiv (2020)
Comon, H., et al.: Tree automata techniques and applications (2007)
Doner, J.E.: Tree acceptors and some of their applications. J. Comput. Syst. Sci. 4(5), 406–451 (1970)
Droste, M., Kuich, W., Vogler, H.: Handbook of Weighted Automata. EATCS Monographs on Theoretical Computer Science. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-01492-5
Ésik, Z., Maletti, A.: The category of simulations for weighted tree automata. Int. J. Found. Comput. Sci. 22(8), 1845–1859 (2011)
Fülöp, Z., Vogler, H.: Weighted tree automata and tree transducers. In: Droste, M., Kuich, W., Vogler, H. (eds.) Handbook of Weighted Automata [8], pp. 313–403. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-01492-5_9
Gécseg, F., Steinby, M.: Tree Automata. Akadémiai Kiadó, Budapest (1984)
Gécseg, F., Steinby, M.: Tree languages. In: Rozenberg, G., Salomaa, A. (eds.) Handbook of Formal Languages, pp. 1–68. Springer, Heidelberg (1997). https://doi.org/10.1007/978-3-642-59126-6_1
Golan, J.S.: Semirings and Their Applications. Kluwer Academic, Dordrecht (1999)
Hall, T.E., Sapir, M.V.: Idempotents, regular elements and sequences from finite semigroups. Discrete Math. 161(1–3), 151–160 (1996)
Hebisch, U., Weinert, H.J.: Semirings-Algebraic Theory and Applications in Computer Science. World Scientific, Singapore (1998)
Högberg, J., Maletti, A., Vogler, H.: Bisimulation minimisation of weighted automata on unranked trees. Fundam. Inform. 92(1–2), 103–130 (2009)
Klimann, I., Lombardy, S., Mairesse, J., Prieur, C.: Deciding unambiguity and sequentiality from a finitely ambiguous max-plus automaton. Theoret. Comput. Sci. 327(3), 349–373 (2004)
Krob, D.: The equality problem for rational series with multiplicities in the tropical semiring is undecidable. Internat. J. Algebra Comput. 4(3), 405–425 (1994)
Mazowiecki, F., Riveros, C.: Pumping lemmas for weighted automata. In: Proceedings of 35th STACS. LIPIcs, vol. 96. Schloss Dagstuhl–Leibniz-Zentrum für Informatik (2018)
Paul, E.: On finite and polynomial ambiguity of weighted tree automata. In: Brlek, S., Reutenauer, C. (eds.) DLT 2016. LNCS, vol. 9840, pp. 368–379. Springer, Heidelberg (2016). https://doi.org/10.1007/978-3-662-53132-7_30
Paul, E.: The equivalence, unambiguity and sequentiality problems of finitely ambiguous max-plus tree automata are decidable. In: Proceedings of 42nd MFCS. LIPIcs, vol. 83. Schloss Dagstuhl–Leibniz-Zentrum für Informatik (2017)
Paul, E.: Finite sequentiality of unambiguous max-plus tree automata. In: Proceedings of 36th STACS. LIPIcs, vol. 126. Schloss Dagstuhl–Leibniz-Zentrum für Informatik (2019)
Rabusseau, G., Balle, B., Cohen, S.B.: Low-rank approximation of weighted tree automata. In: Proceedings of 19th AISTATS. JMLR, vol. 51, pp. 839–847. JMLR.org (2016)
Sakarovitch, J.: Rational and recognisable power series. In: Droste, M., Kuich, W., Vogler, H. (eds.) Handbook of Weighted Automata [8], Chap. 4, pp. 105–174. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-01492-5_4
Salomaa, A., Soittola, M.: Automata-Theoretic Aspects of Formal Power Series. Springer, Heidelberg (2012)
Simon, I.: Limited subsets of a free monoid. In: Proceedings of 19th FOCS, pp. 143–150. IEEE (1978)
Thatcher, J.W.: Characterizing derivation trees of context-free grammars through a generalization of finite automata theory. J. Comput. Syst. Sci. 1(4), 317–322 (1967)
Yu, S.: Regular languages. In: Rozenberg, G., Salomaa, A. (eds.) Handbook of Formal Languages, pp. 41–110. Springer, Heidelberg (1997). https://doi.org/10.1007/978-3-642-59136-5_2
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2021 Springer Nature Switzerland AG
About this paper
Cite this paper
Maletti, A., Nasz, T., Stier, K., Ulbricht, M. (2021). Ambiguity Hierarchies for Weighted Tree Automata. In: Maneth, S. (eds) Implementation and Application of Automata. CIAA 2021. Lecture Notes in Computer Science(), vol 12803. Springer, Cham. https://doi.org/10.1007/978-3-030-79121-6_12
Download citation
DOI: https://doi.org/10.1007/978-3-030-79121-6_12
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-79120-9
Online ISBN: 978-3-030-79121-6
eBook Packages: Computer ScienceComputer Science (R0)