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<Paper uid="P94-1003">
  <Title>PRIORITY UNION AND GENERALIZATION IN DISCOURSE GRAMMARS</Title>
  <Section position="7" start_page="23" end_page="23" type="concl">
    <SectionTitle>
4 Conclusion
</SectionTitle>
    <Paragraph position="0"> In this paper we have reported on an implementation of a discourse grammar in a sign-based formalism, using Carpenter's Attribute Logic Engine (aLE). We extended the discourse grammar and ALE to incorporate the operations of priority union and generalization, operations which we use for resolving parallelism dependent anaphoric expressions. We also reported on a resolution mechanism for verb phrase ellipsis which yields sloppy and strict readings through priority union, and we claimed some advantages of this approach over the use of higher-order unification.</Paragraph>
    <Paragraph position="1"> The outstanding unsolved problem is that of establishing parallelism. While we believe that generalization is an appropriate formal operation to assist in this, we still stand in dire need of a convincing criterion for judging whether the generalization of two categories is sufficiently informative to successfully establish parMlelism.</Paragraph>
  </Section>
class="xml-element"></Paper>