Semantic interpretation and ambiguity

摘要

A new approach to semantic interpretation in natural language understanding is described, together with mechanisms for both lexical and structural disambiguation that work in concert with the semantic interpreter.ABSITY, the system described, is a Montague-inspired semantic interpreter. Like Montague formalisms, its semantics is compositional by design and is strongly typed, with semantic rules in one-to-one correspondence with the meaning-affecting rules of a Marcus parser. The Montague semantic objects—functors and truth conditions—are replaced 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, each of which determines the word or slot's correct sense, in cooperation with the other procedures.It is from the fact that partial results are always well-formed semantic objects that the system gains much of its power. This, in turn, comes from the strict correspondence between syntax and semantics in ABSITY. The result is a foundation for semantic interpretation superior to previous approaches.