Aspectual Modifications to a LCS Database for NLP Applications
MARYLAND UNIV COLLEGE PARK INST FOR ADVANCED COMPUTER STUDIES
Pagination or Media Count:
Verbal and compositional lexical aspect provide the underlying temporal structure of events. Knowledge of lexical aspect, e.g. atelicity, is therefore required for interpreting event sequences in discourse Dowty, 1986 Moens and Steedman, 1988 Passoneau. 1988, interfacing to temporal databases Androutsopoulos, 1996, processing temporal modifiers Antonisse, 1994, describing allowable alternations and their semantic effects Resnik, 1996 Tenny, 1994, and selecting tense and lexical items for natural language generation Dorr and Olsen, 1996 Klavans and Chodorow, 1992, cf. Slobin and Bocaz, 1988. We show that it is possible to represent lexical aspect both verbal and compositional on a large scale, using Lexical Conceptual Structure LCS representations of verbs in the classes cataloged by Levin 1993. We show how proper consideration of these universal pieces of verb meaning may be used to refine lexical representations and derive a range of meanings from combinations of LCS representations. A single algorithm may therefore be used to determine lexical aspect classes and features at both verbal and sentence levels. Finally, we illustrate how knowledge of lexical aspect facilitates the interpretation of events in XLP applications.