Ontology Aspects in Relation Extraction (12)

Problems and pattern dependencies

• Patterns might be ambiguous, and some relations can be expressed implicitely in texts.
• Automatic detection of relations using the described patterns requires syntactic preprocessing.
• Patterns are involved in a network of dependencies between frame name, filler name, and corpus characteristics:

(3) Patterns for a given relation depend on frame name. Cf. patterns with chez, occurring only with PERSON-frames; and different argument positions of frame and filler in patterns with verbs of arity 3 (PERSON vs. ARTEFACT). (6) Patterns for a given relation depend on filler name: Cf. lexical dependence of spatial prepositions from filler-denoting noun.

Workshop Ontologies and Information Extraction
EUROLAN Summer School, Bucharest, 4 August 2003. © Birte Lönneker