Computational aspects of discourse in the context of MUC-3

Discourse comprises those phenomena that usually do not arise when processing a single sentence . It appears to be the most difficult and probably the least understood aspect of automated message understanding. Five out of fifteen sites on a MUC-3 survey listed discourse as their main weakness and an area in which t o concentrate future research . Virtually all systems presented here take a sentence-by-sentence approac h to text understanding . Parsing and domain-dependent interpretation of sentences or sentence fragments (usually the latter) are followed by modules that attempt to connect these interpretations into a coheren t whole. This paper gives an overview of the modules that make the transition from the interpretation of sentences to the interpretation of the text that contains these sentences . Systems presented in this paper exhibit various degrees of the following discourse understanding capabilities :