gh@utai.UUCP (Graeme Hirst) (03/30/84)
COGNITIVE SCIENCE SEMINAR Semantic Interpretation Against Ambiguity Graeme Hirst Department of Computer Science University of Toronto 4pm, Wednesday 4 April, McLuhan Centre for Science and Technology, University of Toronto, 39a Queen's Park Crescent East. ABSTRACT We describe a new approach to semantic interpretation in natural language understanding, and mechanisms for both lexical and structural disambiguation that work in concert with the semantic interpreter. Absity, the system we describe, is a Montague-inspired semantic interpreter. Like Montague formalisms, our semantics are compositional by design, and are strongly typed, with semantic rules in one-to-one correspondence with the meaning-affecting rules of a Marcus parser. We have replaced the Montague semantic objects---functors and truth conditions---with elements of the frame language Frail. Absity's partial results are always well-formed Frail objects. A semantic interpreter must be able to provide feedback to the parser to help it handle structural ambiguities. In Absity, this is done by the Semantic Enquiry Desk, a process that answers the parser's questions on semantic preferences. Disambiguation of word senses and of case slots is done by a set of procedures, one per word or slot, that each determines its correct sense in cooperation with the others. A partially disambiguated procedure's remaining possibilities are well-formed Frail objects that can be seen and used by other processes, including the Semantic Enquiry Desk, just as one can see many of the details of a partly developed instant photograph. -- \\\\ Graeme Hirst University of Toronto Computer Science //// utcsrgv!utai!gh / gh.toronto@csnet-relay / 416-978-6277