French parsing enhanced with a word clustering method based on a syntactic lexicon

International audienceThis article evaluates the integration of data extracted from a French syntactic lexicon, the Lexicon-Grammar (Gross, 1994), into a probabilistic parser. We show that by applying clustering methods on verbs of the French Treebank (Abeillé et al., 2003), we obtain accurate performances on French with a parser based on a Probabilistic Context-Free Grammar (Petrov et al., 2006)

Integration of Data from a Syntactic Lexicon into Generative and Discriminative Probabilistic Parsers

International audienceThis article evaluates the integration of data extracted from a French syntactic lexicon, the Lexicon-Grammar (Gross, 1994), into a probabilistic parser. We show that by applying clustering methods on verbs of the French Treebank (Abeill'e et al., 2003), we obtain accurate performances on French with a parser based on a Probabilistic Context-Free Grammar (Petrov et al., 2006) and a discriminative parser based on a reranking algorithm (Charniak and Johnson, 2005)

Using subcategorization frames to improve French probabilistic parsing

posterInternational audienceThis article introduces results about probabilistic parsing enhanced with a word clustering approach based on a French syntactic lexicon, the Lefff. We show that by applying this clustering method on verbs and adjectives of the French Treebank, we obtain accurate performances on French with a parser based on a Probabilistic Context-Free Grammar

Efficient LFG parsing: SxLfg

International audienceIn this paper, we introduce a new parser, called SxLfg, based on the Lexical-Functional Grammars formalism (LFG). We describe the underlying context-free parser and how functional structures are efficiently computed on top of the CFG shared forest thanks to computation sharing, lazy evaluation, and compact data representation. We then present various error recovery techniques we implemented in order to build a robust parser. Finally, we offer concrete results when SxLfg is used with an existing grammar for French. We show that our parser is both efficient and robust, although the grammar is very ambiguous

Feature-based and Model-based Semantics for English, French and German Verb Phrases

This paper considers the relative merits of using features and formal event models to characterise the semantics of English, French and German verb phrases, and con- siders the application of such semantics in machine translation. The feature-based ap- proach represents the semantics in terms of feature systems, which have been widely used in computational linguistics for representing complex syntactic structures. The paper shows how a simple intuitive semantics of verb phrases may be encoded as a feature system, and how this can be used to support modular construction of au- tomatic translation systems through feature look-up tables. This is illustrated by automated translation of English into either French or German. The paper contin- ues to formalise the feature-based approach via a model-based, Montague semantics, which extends previous work on the semantics of English verb phrases. In so doing, repercussions of and to this framework in conducting a contrastive semantic study are considered. The model-based approach also promises to provide support for a more sophisticated approach to translation through logical proof; the paper indicates further work required for the fulfilment of this promise

Syntactic variation and diglossia in French

The present article addresses syntactic variation within French, and is an example of a relatively recent shift in attitude towards variation in this language. It considers the status of the variation with respect to the mental grammars of speakers, in particular in the light of Massot’s work suggesting that contemporary metropolitan France is characterised by diglossia, that is, a community of speakers with two (in this case massively overlapping but not entirely identical) ‘French’ grammars which co-exist in their minds, one stylistically marked High, the other Low. The article reviews one particular instance of variation and argues that Massot’s model needs to be revised in order to account for the particular phenomenon of surface forms which can be generated by both putative grammars but which have a different linguistic status in each

Assumptions behind grammatical approaches to code-switching: when the blueprint is a red herring

Many of the so-called ‘grammars’ of code-switching are based on various underlying assumptions, e.g. that informal speech can be adequately or appropriately described in terms of ‘‘grammar’’; that deep, rather than surface, structures are involved in code-switching; that one ‘language’ is the ‘base’ or ‘matrix’; and that constraints derived from existing data are universal and predictive. We question these assumptions on several grounds. First, ‘grammar’ is arguably distinct from the processes driving speech production. Second, the role of grammar is mediated by the variable, poly-idiolectal repertoires of bilingual speakers. Third, in many instances of CS the notion of a ‘base’ system is either irrelevant, or fails to explain the facts. Fourth, sociolinguistic factors frequently override ‘grammatical’ factors, as evidence from the same language pairs in different settings has shown. No principles proposed to date account for all the facts, and it seems unlikely that ‘grammar’, as conventionally conceived, can provide definitive answers. We conclude that rather than seeking universal, predictive grammatical rules, research on CS should focus on the variability of bilingual grammars

Developing a TT-MCTAG for German with an RCG-based parser

Developing linguistic resources, in particular grammars, is known to be a complex task in itself, because of (amongst others) redundancy and consistency issues. Furthermore some languages can reveal themselves hard to describe because of specific characteristics, e.g. the free word order in German. In this context, we present (i) a framework allowing to describe tree-based grammars, and (ii) an actual fragment of a core multicomponent tree-adjoining grammar with tree tuples (TT-MCTAG) for German developed using this framework. This framework combines a metagrammar compiler and a parser based on range concatenation grammar (RCG) to respectively check the consistency and the correction of the grammar. The German grammar being developed within this framework already deals with a wide range of scrambling and extraction phenomena