Combining statistical techniques and lexico-syntactic patterns for semantic relations extraction from text

We describe here a methodology to combine two different techniques for Semantic Relation Extraction from texts. On the one hand, generic lexicosyntactic patterns are applied to the linguistically analyzed corpus to detect a first set of pairs of co-occurring words, possibly involved in "syntagmatic" relations. On the other hand, a statistical unsupervised association system is used to obtain a second set of pairs of "distributionally similar" terms, that appear to occur in similar contexts, thus possibly involved in "paradigmatic" relations. The approach aims at learning ontological information by filtering the candidate relations obtained through generic lexico-syntactic patterns and by labelling the anonymous relations obtained through the statistical system. The resulting set of relations can be used to enrich existing ontologies and for semantic annotation of documents or web pages.