Results 21 to 30 of about 14,474 (287)
Absence of phase transition in random language model
The random language model, proposed as a simple model of human languages, is defined by the averaged model of a probabilistic context-free grammar. This grammar expresses the process of sentence generation as a tree graph with nodes having symbols as ...
Kai Nakaishi, Koji Hukushima
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A Context-Free Grammar of One Rhythmic Model of Russian Verse
A formal model of the Russian verse based on the accentual segmentation of its structure is offered and considered. A context-free grammar (in N. Chomsky’s sense) which generates correct rhythmic forms of the presented model is constructed.
V. N. Boykov
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Equivalent Transformations and Regularization in Context-Free Grammars
Regularization of translational context-free grammar via equivalent transformations is a mandatory step in developing a reliable processor of a formal language defined by this grammar.
Fedorchenko Ludmila, Baranov Sergey
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Complexity of Problems of Commutative Grammars [PDF]
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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In this paper we develop a theory of context-free graph grammars. Formal properties of such grammars are proven, with particular attention to graph language recognizability.
Pierluigi Della Vigna, GHEZZI, CARLO
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Fatgraph models of RNA structure
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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On the Order Type of Scattered Context-Free Orderings [PDF]
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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An Online Algorithm for Lightweight Grammar-Based Compression
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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The Triple-Pair Construction for Weighted ω-Pushdown Automata [PDF]
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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Consistent Unsupervised Estimators for Anchored PCFGs
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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