A Progress Report on the Discourse and Reference Components of PAL
This paper reports on research being conducted on a computer assistant, called PAL. PAL is being designed to arrange various kinds of events with concern for the who, what, when, where and why of that event. The goal for PAL is to permit a speaker to interact with it in English and to use extended discourse to state the speaker's requirements. The portion of the language system discussed in this report disambiguates references from discourse and interprets the purpose of sentences of the discourse. PAL uses the focus of discourse to direct its attention to a portion of the discourse and to the database to which the discourse refers. The focus makes it possible to disambiguate references with minimal search. Focus and a frames representation of the discourse make it possible to interpret discourse purposes. The focus and representation of the discourse are explained, and the computational components of PAL which implement reference disambiguation and discourse interpretation are presented in detail.