Results 21 to 30 of about 17,181 (262)
Implicit learning of recursive context-free grammars.
PLoS ONE, 2012 Context-free grammars are fundamental for the description of linguistic syntax. However, most artificial grammar learning experiments have explored learning of simpler finite-state grammars, while studies exploring context-free grammars have not assessed
Martin Rohrmeier +2 more
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Complexity of Problems of Commutative Grammars [PDF]
Logical Methods in Computer Science, 2015 We consider commutative regular and context-free grammars, or, in other words, Parikh images of regular and context-free languages. By using linear algebra and a branching analog of the classic Euler theorem, we show that, under an assumption that the ...
Eryk Kopczynski
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Fatgraph models of RNA structure
Computational and Mathematical Biophysics, 2017 In this review paper we discuss fatgraphs as a conceptual framework for RNA structures. We discuss various notions of coarse-grained RNA structures and relate them to fatgraphs.We motivate and discuss the main intuition behind the fatgraph model and ...
Huang Fenix +2 more
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Consistent Unsupervised Estimators for Anchored PCFGs
Transactions of the Association for Computational Linguistics, 2020 Learning probabilistic context-free grammars (PCFGs) from strings is a classic problem in computational linguistics since Horning ( 1969 ). Here we present an algorithm based on distributional learning that is a consistent estimator for a large class of ...
Clark, Alexander, Fijalkow, Nathanaël
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On the Order Type of Scattered Context-Free Orderings [PDF]
Electronic Proceedings in Theoretical Computer Science, 2019 We show that if a context-free grammar generates a language whose lexicographic ordering is well-ordered of type less than ω^2, then its order type is effectively computable.
Kitti Gelle, Szabolcs Iván
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Superregular grammars do not provide additional explanatory power but allow for a compact analysis of animal song [PDF]
Royal Society Open Science, 2019 A pervasive belief with regard to the differences between human language and animal vocal sequences (song) is that they belong to different classes of computational complexity, with animal song belonging to regular languages, whereas human language is ...
T. Morita, H. Koda
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The Triple-Pair Construction for Weighted ω-Pushdown Automata [PDF]
Electronic Proceedings in Theoretical Computer Science, 2017 Let S be a complete star-omega semiring and Sigma be an alphabet. For a weighted omega-pushdown automaton P with stateset 1...n, n greater or equal to 1, we show that there exists a mixed algebraic system over a complete semiring-semimodule pair ((S ...
Manfred Droste +2 more
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Inductive Synthesis of Cover-Grammars with the Help of Ant Colony Optimization
Foundations of Computing and Decision Sciences, 2016 A cover-grammar of a finite language is a context-free grammar that accepts all words in the language and possibly other words that are longer than any word in the language.
Wieczorek Wojciech
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On the Size Complexity of Non-Returning Context-Free PC Grammar Systems [PDF]
Electronic Proceedings in Theoretical Computer Science, 2009 Improving the previously known best bound, we show that any recursively enumerable language can be generated with a non-returning parallel communicating (PC) grammar system having six context-free components.
Erzsébet Csuhaj-Varjú, György Vaszil
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An Online Algorithm for Lightweight Grammar-Based Compression
Algorithms, 2012 Grammar-based compression is a well-studied technique to construct a context-free grammar (CFG) deriving a given text uniquely. In this work, we propose an online algorithm for grammar-based compression.
Masayuki Takeda +2 more
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