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A unifying survey on weighted logics and weighted automata

Core weighted logic: minimal and versatile specification of quantitative properties

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Abstract

Logical formalisms equivalent to weighted automata have been the topic of numerous research papers in the recent years. It started with the seminal result by Droste and Gastin on weighted logics over semirings for words. It has been extended in two dimensions by many authors. First, the weight domain has been extended to valuation monoids, valuation structures, etc. to capture more quantitative properties. Along another dimension, different structures such as ranked or unranked trees, nested words, Mazurkiewicz traces, etc. have been considered. The long and involved proofs of equivalences in all these papers are implicitly based on the same core arguments. This article provides a meta-theorem which unifies these different approaches. Towards this, we first revisit weighted automata by defining a new semantics for them in two phases—an abstract semantics based on multisets of weight structures (independent of particular weight domains) followed by a concrete semantics. Then, we introduce a core weighted logic with a minimal number of features and a simplified syntax, and lift the new semantics to this logic. We show at the level of the abstract semantics that weighted automata and core weighted logic have the same expressive power. Finally, we show how previous results can be recovered from our result by logical reasoning. In this paper, we prove the meta-theorem for words, ranked and unranked trees, showing the robustness of our approach.

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Notes

  1. This valuation does not satisfy \(\mathsf {Sq}(s)=s\).

  2. We do not require that \(\mathsf {Val}(r)=r\) for all \(r\in U\) as in Droste and Perevoshchikov (2013).

  3. Actually, (3) holds for arbitrary multisets \(A_i,B_j\in \mathbb {N} \langle R \rangle \).

  4. As already noticed in Droste and Meinecke (2012), a simple projection does not work. Indeed, it would result in transition labels that are multisets of weights, which is not possible since our theorem requires the same set of weights for the automaton and the formula.

  5. We could also use an unambiguous automaton for \(\mathcal A_\varphi \).

  6. These formulæ are call strongly \(\wedge \)-restricted in Droste and Meinecke (2012), in contrast with a slightly less restrained fragment of \(\wedge \)-restricted formulæ.

  7. In Droste and Meinecke (2012), the regularity is defined with respect to some weighted automata. Here, we prefer to use a purely logical definition. However, using Corollary 11-2., those two definitions are equivalent.

  8. The product in the semiring of weight sequences is based on the concatenation of sequences. There is no natural counterpart for trees.

  9. Equivalently, we may assume that transitions are disjoint: if \((L,a,q),(L',a,q)\in \Delta \) then \(L=L'\) or \(L\cap L'=\emptyset \). In this case, a run can be defined as a simpler Q-tree \(\rho \) with \(\mathrm {dom}(\rho )=\mathrm {dom}(t)\) and such that for all \(u\in \mathrm {dom}(t)\) there is a (unique) transition \((L,t(u),\rho (u))\in \Delta \) with \(\rho (u\cdot 1)\ldots \rho (u\cdot \mathsf {ar}(u))\in L\).

  10. An even simpler formula can be obtained in the simpler setting of ranked trees.

References

  • Albert J, Kari J (2009) Digital image compression. In: Kuich W, Vogler H, Droste M (eds) Handbook of Weighted Automata, EATCS Monographs in Theoretical Computer Science, chap. 5. Springer, pp. 445–472

  • Bollig B, Gastin P (2009) Weighted versus probabilistic logics. In: Proceedings of the 13th international conference on developments in language theory (DLT’09), Lecture Notes in Computer Science, vol. 5583, Springer, pp. 18–38

  • Büchi JR (1960) Weak second-order arithmetic and finite automata. Zeitschrift für Mathematische Logik und Grundlagen der Mathematik 6:66–92

    Article  MathSciNet  MATH  Google Scholar 

  • Černý P, Chatterjee K, Henzinger TA, Radhakrishna A, Singh R (2011) Quantitative synthesis for concurrent programs. In: Proceedings of the 23rd international conference on computer aided verification (CAV’11), Lecture Notes in Computer Science, vol 6806, Springer, pp. 243–259

  • Comon-Lundh H, Dauchet M, Gilleron R, Jacquemard F, Lugiez D, Tison S, Tommasi M (2008) Tree automata techniques and applications. http://tata.gforge.inria.fr/

  • Droste M, Gastin P (2007) Weighted automata and weighted logics. Theor Comput Sci 380(1–2):69–86

  • Droste M, Götze D, Märcker S, Meinecke I (2011) Weighted tree automata over valuation monoids and their characterization by weighted logics. In: Algebraic Foundations in Computer Science, Lecture Notes in Computer Science, vol 7020, Springer, pp. 30–55

  • Droste M, Heusel D, Vogler H (2015) Weighted unranked tree automata over tree valuation monoids and their characterization by weighted logics. In: Proceedings of the 6th international conference on algebraic informatics (CAI’15), Lecture Notes in Computer Science, vol 9270, Springer, pp. 90–102

  • Droste M, Kuich W (2009) Semirings and formal power series. In: Droste M, Kuich W, Vogler H (eds) Handbook of weighted automata, EATCS monographs in theoretical computer science, chap. 1, Springer, pp. 3–27

  • Droste M, Meinecke I (2012) Weighted automata and weighted MSO logics for average and long-time behaviors. Inf Comput 220–221:44–59

    Article  MathSciNet  MATH  Google Scholar 

  • Droste M, Perevoshchikov V (2013) Multi-weighted automata and MSO logic. In: Proceedings of the 8th international computer science symposium in Russia (CSR’13), Lecture Notes in Computer Science. vol. 7913, Springer, pp 418–430

  • Droste M, Perevoshchikov V (2014) A Nivat theorem for weighted timed automata and weighted relative distance logic. In: Proceedings of the 41st international colloquium on automata, languages and programming (ICALP’14), Lecture Notes in Computer Science, vol. 8573, Springer, pp. 171–182

  • Droste M, Vogler H (2006) Weighted tree automata and weighted logics. Theor Comput Sci 366(3):228–247

    Article  MathSciNet  MATH  Google Scholar 

  • Droste M, Vogler H (2011) Weighted logics for unranked tree automata. Theory Comput Syst 48:23–47

    Article  MathSciNet  MATH  Google Scholar 

  • Elgot CC (1961) Decision problems of finite automata design and related arithmetics. Trans Am Math Soc 98:21–52

    Article  MathSciNet  MATH  Google Scholar 

  • Fülöp Z, Stüber T, Vogler H (2012) A Büchi-like theorem for weighted tree automata over multioperator monoids. Theory Comput Syst 50:241–278

    Article  MathSciNet  MATH  Google Scholar 

  • Knight K, May J (2009) Applications of weighted automata in natural language processing. In: Droste M, Kuich W, Vogler H (eds) Handbook of weighted automata, EATCS monographs in theoretical computer science, chap. 14, Springer, pp 555–579

  • Kuich W, Salomaa A (1985) Semirings. Automata and Languages. EATCS Monographs in Theoretical Computer Science. Springer-Verlag

  • Perevoshchikov V (2015) Multi-weighted automata models and quantitative logics. Ph.D. thesis, Universität Leipzig

  • Schützenberger MP (1961) On the definition of a family of automata. Inf Control 4:245–270

    Article  MathSciNet  MATH  Google Scholar 

  • Thatcher JW, Wright JB (1968) Generalized finite automata theory with an application to a decision problem of second-order logic. Math Syst Theory 2(1):57–81

    Article  MathSciNet  MATH  Google Scholar 

  • Trakhtenbrot BA (1961) Finite automata and logic of monadic predicates. Doklady Akademii Nauk SSSR 149:326–329

    Google Scholar 

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Correspondence to Benjamin Monmege.

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The authors declare that they have no conflict of interest.

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Communicated by M. Droste, Z. Esik and K. Larsen.

Part of the research leading to these results was achieved when the second author was at Université libre de Bruxelles (Belgium), and has received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under Grant Agreement n601148 (CASSTING).

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Gastin, P., Monmege, B. A unifying survey on weighted logics and weighted automata. Soft Comput 22, 1047–1065 (2018). https://doi.org/10.1007/s00500-015-1952-6

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