Preference semantics for message understanding

Abstract

The design of effective natural language processing systems requires a combination of the theoretical and the practical. We want to have a theoretically well-founded design so that we can take advantage of gradual improvements in our knowledge of syntax, semantics, discourse structures, and the subject domain. At the same time we need to adopt a practical approach which recognizes the inevitable shortcomings of our knowledge in these areas. We need to create robust systems which are able to deal appropriately with these shortcomings. We are interested in particular in systems for extracting specified information from a text. Such systems are robust if they are able to extract at least partial information despite the presence of ill-formed or unexpected syntactic, semantic, or discourse structures.