Results 1 to 10 of about 283,476 (338)
Implicit learning of recursive context-free grammars. [PDF]
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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LPG–PCFG: An Improved Probabilistic Context- Free Grammar to Hit Low-Probability Passwords [PDF]
Sensors, 2022 With the development of the Internet, information security has attracted more attention. Identity authentication based on password authentication is the first line of defense; however, the password-generation model is widely used in offline password ...
Xiaozhou Guo +4 more
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Learning of Structurally Unambiguous Probabilistic Grammars [PDF]
Logical Methods in Computer Science, 2023 The problem of identifying a probabilistic context free grammar has two aspects: the first is determining the grammar's topology (the rules of the grammar) and the second is estimating probabilistic weights for each rule.
Dana Fisman +2 more
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Learning Cover Context-Free Grammars from Structural Data [PDF]
Scientific Annals of Computer Science, 2014 We consider the problem of learning an unknown context-free gram- mar from its structural descriptions with depth at most ℓ. The structural descriptions of the context-free grammar are its unlabelled derivation trees. The goal is to learn a cover context-
M. Marin, G. Istrate
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A stochastic context free grammar based framework for analysis of protein sequences [PDF]
BMC Bioinformatics, 2009 Background In the last decade, there have been many applications of formal language theory in bioinformatics such as RNA structure prediction and detection of patterns in DNA.
Nebel Jean-Christophe, Dyrka Witold
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A universal context-free grammar [PDF]
Information and Control, 1975 In this report we show that, for each alphabet Σ, there exists a context-free grammar G which satisfies the property that for each context-free language L ⊆ Σ* a regular control set C can be found such that LC(G ...
Kasai, Takumi
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On a property of probabilistic context-free grammars [PDF]
International Journal of Mathematics and Mathematical Sciences, 1983 It is proved that for a probabilistic context‐free language L(G), the population density of a character (terminal symbol) is equal to its relative density in the words of a sample S from L(G) whenever the production probabilities of the grammar G are estimated by the relative frequencies of the corresponding productions in the sample.
Ranjan Chaudhuri, A.N.V. Rao
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Reduction of context-free grammars [PDF]
Information and Control, 1970 This paper is concerned with the following problem: Given a context-free grammar G, find a context-free grammar with the fewest nonterminal symbols or with the fewest rules that is equivalent to G.
Kasami, Tadao, Taniguchi, Kenichi
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Translations on a context free grammar [PDF]
Information and Control, 1971 Two schemes for the specification of translations on a context-free grammar are proposed. The first scheme, called a generalized syntax directed translation (GSDT), consists of a context free grammar with a set of semantic rules associated with each ...
Aho, A.V., Ullman, J.D.
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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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