<?xml version="1.0" standalone="yes"?>
<Paper uid="C00-2133">
  <Title>Prosody and the Resolution of Pronominal Anaphora</Title>
  <Section position="8" start_page="923" end_page="924" type="concl">
    <SectionTitle>
6 Conclusion and Outlook
</SectionTitle>
    <Paragraph position="0"> In this paper, we cxamincd patterns of acoustic prosodic highlighting of personal and demonstrative pronouns in a corpus of task-oriented spontaneous dialog. To our knowledge, this is the lirst comparative study of this kind. Wc used a straightforward, theory-neutral operationalization of &amp;quot;prosodic highlighting&amp;quot; that does not depend on complex algorithms for F0 stylization or (focal) accent detection and is thus very easy to incorporate into any real-time spoken dialog system. We chose a spoken dialog corpus that includes demonstrativc pronouns because demonstratives are both a prominent feature of problem-solving dialogs and a sorely neglected lield of study. In particular, we asked two questions: Do Speakers Signal Antecedent Properties Acoustically? Based on our data, the answer to this question is: If they do,/hey do it in a highly idiosyncratic way. We cannot posit any safe generalizations over several speakers, and li&amp;quot;om the perspective of an NLP application, such generalizations might even be dangerous. In order to evaluate the impact of speaker strategies on the resolution of pronouns, we need more data - 150 to 200 pronouns from 4-5 speakers each. Collecting this amount of data in a dedicated corpus is inefficient. Therefore, further acoustic investigations do not make much sense at this point; rather, the data should be examined carefully for tendencies which can form the basis for dedicated production and perception experiments which arc explicitly designed for uncovering inter-speaker variation.</Paragraph>
    <Paragraph position="1"> Are Acoustic Features Useful for Pronoun Resolution? The answer is: probably not. At least for this corpus, we were not able to determine any numerical heuristics that could be utilized to aid pronoun resolution. The logistic regression experiments show that on a speaker-independent basis, logarithmic duration might well be a reliable cue to certain aspects of a pronoun's antecedent. In order to incorporate prosodic cues into an actual algorithm, we will need more training material and a principled evaluation procedure. We will also need to take into account other influences, such as dialog acts and dialog structure.</Paragraph>
    <Paragraph position="2"> Acknowledgements. Wc would like to thank the three anonymous reviewers, Rebecca Passonneau, Lncicn Galescu, James Alhm, Michael Strube, Dictmar Lancd and Wolf gang Hess for their comments on earlier vet'sions of this work. Donna K. Byron was funded by ONR research grant N00014-95-1-1088 and Columbia University/NSF research grant OPG:1307. For all statistical analyses, wc used R (Ihaka and Gentleman, 1996).</Paragraph>
  </Section>
class="xml-element"></Paper>