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DECO Local grammar Graph (LGG) formalism   





Local grammar Graph (LGG) formalism is a Finite-State Grammar proposed by Maurice Gross (1997, 1999). It is represented by Directed Acyclic Graphs (DAGs) and transformed into Finite-State Transducer (FST) in UNITEX platform.


Local grammar Graphs allow to catch some rare linguistic phenomena. Jargon, idioms or clichés that, provoking common syntactic constraints, can be described locally without more powerful syntactic formalism. A local grammar may describe a set of forbidden or unavoidable sequences as well. In both cases, it can be represented by a finite-state automaton (FSA) or a finite-state transducer (FST).


Local Grammar Graph (LGG)



A collection of local grammars can be combined and represented by a more complex finite automaton by the union of the simpler local grammar automata. Novel linguistic studies keep increasing the number of local grammars and one can refer to the section CORPORA & TOOLS > Local Grammar Graphs.





Gross, M. 1997. The Construction of Local grammars. Finite-Sate Language Processing. The MIT Press. 


Silberztein, M. 1997. The Lexical Analysis of Natural Languages. Finite-Sate Language Processing. The MIT Press.




UNITEX Platform



Unitex is a collection of programs developed for the analysis of texts in natural language by using linguistic resources. These resources consist of electronic dictionaries, local grammar graphs and lexicon-grammar tables.


It is initially developed for French at the Laboratoire d’Automatique Documentaire et Linguistique (LADL) at University Paris 7, and extended to be compatible with the linguistic resources of other languages such as Greek, Italian, German, Spanish or Korean.  


UNITEX is a text processing system, based on automata-oriented technology. In this platform, one can construct electronic resources such as dictionaries and grammars and apply them in text processing. The main functions are as follows:


● Building, modifying and applying electronic dictionaries;

● Pattern matching with regular expressions and transition networks (Local Grammar Graphs)

● Applying lexicon-grammar tables

● Treating ambiguity via text automaton


This program can be downloaded from the following site: 






Paumier, S. 2000. Unitex Manual. Université Paris-Est Marne-la-Vallée: Paris. 


Silberztein, M. 1993 Dictionnaires électroniques et analyse automatique de textes - le système INTEX. Paris: Masson.