Question answering from structured knowledge sources

• DOI: 10.1016/j.jal.2005.12.006
• Publication Date: 2006-01-28T07:10:36Z
• Authors: Anette Frank; Hans-Ulrich Krieger; Feiyu Xu; Hans Uszkoreit; Berthold Crysmann; Brigitte Jörg; Ulrich Schäfer
• Keywords: Hybrid NLP; Multilinguality; Logic; Data base queries; Applied Mathematics; 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology; QA; Question semantics; RMRS; Ontology modeling

AbstractWe present an implemented approach for domain-restricted question answering from structured knowledge sources, based on robust semantic analysis in a hybrid NLP system architecture. We perform question interpretation and answer extraction in an architecture that builds on a lexical-conceptual structure for question interpretation, which is interfaced with domain-specific concepts and properties in a structured knowledge base. Question interpretation involves a limited amount of domain-specific inferences, and accounts for higher-level quantificational questions. Question interpretation and answer extraction are modular components that interact in clearly defined ways. We derive so-called proto queries from the linguistic representations, which provide partial constraints for answer extraction from the underlying knowledge sources. The search queries we construct from proto queries effectively compute minimal spanning trees from the underlying knowledge sources. Our approach naturally extends to multilingual question answering, and has been developed as a prototype system for two application domains: the domain of Nobel prize winners, and the domain of Language Technology, on the basis of the large ontology underlying the information portal LT World.