Automatic construction and validation of French large lexical resources. Reuse of verb theoretical linguistic descriptions
Nabil Hathout, Fiammetta Namer · 1998
We address in this paper some problems related to the reuse for NLP of LADL's Lexicon-Grammar (LG). This major source of French verbs lexical knowledge has been publicly available on the Internet for several years. However, it has not been used by the NLP community, mainly because of its format: ASCII files each of them containing a table with binary values (+/\\Gamma). The interpretation of these tables is non trivial because large parts of the linguistic informations they contain are neither explicit nor represented in a uniform manner. The paper presents 3 aspects of the research: (1) The translation of LG into a PATR-II Intermediate Lexicon (IL). The aim of this translation is to normalize and to represent explicitly the lexical properties encoded in LG tables. IL representations are independent of any particular linguistic theory. (2) IL is used to generate lexicons for NLP applications based on unification grammars. We have build an HPSG lexicon used within the ALEP system to parse French, and a TAG lexicon used for French text generation. These lexicons are dual of one another since, for a each entry, the first represents the properties that hold while the later represents the ones that do not hold. The generation of these lexicons raises interesting questions regarding the lexicon organization in these theories. (3) The evaluation of LG coverage on a corpus. This evaluation uses a French shallow parser able to recognize quite precisely the constituents that the verbs take as arguments. The lexical descriptions of the verbs can then be saturated in order to recognize the phrases headed by these verbs.