BACKGROUND AND MOTIVATION In 1988 Professor Wendy Lehnert completed the initial implementation of a semantically-oriente d sentence analyzer named CIRCUS [1] . The original design for CIRCUS was motivated by two basi c research interests : (1) we wanted to increase the level of syntactic sophistication associated wit h semantically-oriented parsers, and (2) we wanted to integrate traditional symbolic techniques i n natural language processing with connectionist techniques in an effort to

more »

... the complementar y strengths of these two computational paradigms . Shortly thereafter, two graduate students, Claire Cardie and Ellen Riloff, began to experimen t with CIRCUS as a mechanism for analyzing citation sentences in the scientific literature [2] . The key idea behind this work was to extract a relatively abstract level of information from each sentence , using only a limited vocabulary that was hand-crafted to handle a restricted set of target concepts . We called this mode of language processing selective concept extraction, and the basic style of sentenc e analysis was a type of text skimming . This project provided us with an opportunity to give CIRCUS a workout and determine whether or not the basic design was working as expected .