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The Equivalence Of Four Extensions Of ContextFree Grammars
 Mathematical Systems Theory
, 1994
"... There is currently considerable interest among computational linguists in grammatical formalisms with highly restricted generative power. This paper concerns the relationship between the class of string languages generated by several such formalisms viz. Combinatory Categorial Grammars, Head Grammar ..."
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Cited by 96 (5 self)
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There is currently considerable interest among computational linguists in grammatical formalisms with highly restricted generative power. This paper concerns the relationship between the class of string languages generated by several such formalisms viz. Combinatory Categorial Grammars, Head Grammars, Linear Indexed Grammars and Tree Adjoining Grammars. Each of these formalisms is known to generate a larger class of languages than ContextFree Grammars. The four formalisms under consideration were developed independently and appear superficially to be quite different from one another. The result presented in this paper is that all four of the formalisms under consideration generate exactly the same class of string languages. 1 Introduction There is currently considerable interest among computational linguists in grammatical formalisms with highly restricted generative power. This is based on the argument that a grammar formalism should not merely be viewed as a notation, but as part o...
Parsing Some Constrained Grammar Formalisms
 Computational Linguistics
, 1994
"... this paper we present a scheme to extend a recognition algorithm for ContextFree Grammars (CFG) that can be used to derive polynomialtime recognition algorithms for a set of formalisms that generate a superset of languages generated by CFG. We describe the scheme by developing a CockeKasamiYoung ..."
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Cited by 61 (6 self)
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this paper we present a scheme to extend a recognition algorithm for ContextFree Grammars (CFG) that can be used to derive polynomialtime recognition algorithms for a set of formalisms that generate a superset of languages generated by CFG. We describe the scheme by developing a CockeKasamiYounger (CKY)like pure bottomup recognition algorithm for Linear Indexed Grammars and show how it can be adapted to give algorithms for Tree Adjoining Grammars and Combinatory Categorial Grammars. This is the only polynomialtime recognition algorithm for Combinatory Categorial Grammars that we are aware of
Grammatical Acquisition: Inductive Bias and Coevolution of Language and the Language Acquisition Device
 Language
, 2000
"... An account of grammatical acquisition is developed within the parametersetting framework applied to a generalized categorial grammar (GCG). The GCG is embedded in a default inheritance network yielding a natural partial ordering (reflecting generality) of parameters which determines a partial ord ..."
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Cited by 60 (0 self)
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An account of grammatical acquisition is developed within the parametersetting framework applied to a generalized categorial grammar (GCG). The GCG is embedded in a default inheritance network yielding a natural partial ordering (reflecting generality) of parameters which determines a partial order for parameter setting. Computational simulation shows that several resulting acquisition procedures are effective on a parameter set expressing major typological distinctions based on constituent order, and defining 70 distinct full languages and over 200 subset languages. The effects on acquisition of inductive bias, that is, of differing initial parameter settings, are explored via computational simulation. Computational simulation of populations of language learners and users instantiating the acquisition model show: 1) that variant acquisition procedures, with differing inductive biases, exert differing selective pressures on the evolution of language(s); 2) acquisition proc...
Dynamic Dependency Grammar
 Linguistics and Philosophy
, 1994
"... this paper. Thanks are also due to Steve Pulman, Ewan Klein, David Beaver and Guy Barry for discussion during the early stages of the work, and to other members of the University of Edinburgh Centre for Cognitive Science and the University of Cambridge Computer Laboratory. The research was supported ..."
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Cited by 50 (4 self)
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this paper. Thanks are also due to Steve Pulman, Ewan Klein, David Beaver and Guy Barry for discussion during the early stages of the work, and to other members of the University of Edinburgh Centre for Cognitive Science and the University of Cambridge Computer Laboratory. The research was supported by the British Science and Engineering Research Council (Research Fellowship B/90/ITF/288, and Research Grant RR30718)
A Compositional DRSbased Formalism for NLP Applications
 In International Workshop on Computational Semantics
, 1994
"... This paper describes and discusses the formalism which forms the backbone of semantic processing in the verbmobil spoken dialogue translation project. In the first part, the theoretical core of the formalism is presented: DRT, a compositional version of Discourse Representation Theory. The main par ..."
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Cited by 35 (7 self)
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This paper describes and discusses the formalism which forms the backbone of semantic processing in the verbmobil spoken dialogue translation project. In the first part, the theoretical core of the formalism is presented: DRT, a compositional version of Discourse Representation Theory. The main part describes the implementation of DRT, as a worked out semantic representation language for the Verbmobil project, which is designed to meet the special requirements of the application. Finally, we discuss future extensions and modifications of the formalism. Thanks We would like to thank Chris Fox and our colleagues in the verbmobil project, especially those in the semantics, dialogue and translation workpackages. The authors are solely responsible for the views expressed in this paper. Contents 1 DRT 3 2 The verbmobil Core Semantic Formalism 5 3 Extensions to Core Formalism 9 4 A Worked Example 11 5 Conclusion 14 1 DRT It has been recognized that formalisms for semantic constru...
POLYNOMIAL TIME PARSING OF COMBINATORY CATEGORIAL GRAMMARS
 IN PROCEEDINGS OF THE 28TH ANNUAL MEETING OF THE ASSOCIATION FOR COMPUTATIONAL LINGUISTICS
, 1990
"... In this paper we present a polynomial time parsing algorithm for Combinatory Categorial Grammar. The recognition phase extends the CKY algorithm for CFG. The process of generating a representation of the parse trees has two phases. Initially, a shared for est is build that encodes the set of all de ..."
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Cited by 35 (0 self)
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In this paper we present a polynomial time parsing algorithm for Combinatory Categorial Grammar. The recognition phase extends the CKY algorithm for CFG. The process of generating a representation of the parse trees has two phases. Initially, a shared for est is build that encodes the set of all derivation trees for the input string. This shared forest is then pruned to remove all spurious ambiguity.
The GF Resource grammar library
 August
, 2002
"... The GF Resource Grammar Library is a set of natural language grammars implemented in GF (Grammatical Framework). These grammars are in a strong sense parallel: they are built upon a common abstract syntax, i.e. a common tree structure. Individual languages are obtained via compositional mappings fro ..."
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Cited by 32 (7 self)
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The GF Resource Grammar Library is a set of natural language grammars implemented in GF (Grammatical Framework). These grammars are in a strong sense parallel: they are built upon a common abstract syntax, i.e. a common tree structure. Individual languages are obtained via compositional mappings from abstract syntax trees to feature structures specific to each language. The grammar defines, for each language, a complete set of morphological paradigms and a syntax fragment comparable to CLE (Core Language Engine). It is available as opensource software under the GNU LGPL License.
Expressivity and complexity of the Grammatical Framework
 Göteborg University and Chalmers University of Technology, Gothenburg, Sweden
, 2004
"... Varje varelse, varje skapelse, varje dröm som människan n˚agonsin drömt finns här. Ni formade dem i era drömmar och fabler och i era böcker, ni gav dem form och substans och ni trodde p˚a dem och gav dem makt att göra det och det ända tills de fick eget liv. Och sedan övergav ni dem. i Lundwall (197 ..."
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Cited by 21 (5 self)
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Varje varelse, varje skapelse, varje dröm som människan n˚agonsin drömt finns här. Ni formade dem i era drömmar och fabler och i era böcker, ni gav dem form och substans och ni trodde p˚a dem och gav dem makt att göra det och det ända tills de fick eget liv. Och sedan övergav ni dem. i Lundwall (1974, p. 114) ii This thesis investigates the expressive power and parsing complexity of the grammatical framework (gf), a formalism originally designed for displaying formal propositions and proofs in natural language. This is done by relating gf with two more wellknown grammar formalisms; generalized contextfree grammar (gcfg), best seen as a framework for describing various grammar formalisms; and parallel multiple contextfree grammar (pmcfg), an instance of gcfg. Since gf is a fairly new theory, some questions about expressivity and parsing complexity have until now not been answered; and these questions are the main focus of this thesis. The main result is that the important subclass contextfree gf is equivalent to pmcfg, which has polynomial parsing complexity, and whose expressive power is fairly well known. Furthermore, we give a number of tabular parsing algorithms for pmcfg with polynomial complexity, by extending existing algorithms for contextfree grammars. We suggest three possible extensions of gf/pmcfg, and discuss how the expressive power and parsing complexity are influenced. Finally, we discuss the parsing problem for unrestricted gf grammars, which is undecidable in general. We nevertheless describe a procedure for parsing grammars containing higherorder functions and dependent types.