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<Paper uid="W04-3239">
  <Title>A Boosting Algorithm for Classification of Semi-Structured Text</Title>
  <Section position="1" start_page="0" end_page="0" type="abstr">
    <SectionTitle>
Abstract
</SectionTitle>
    <Paragraph position="0"> The focus of research in text classification has expanded from simple topic identification to more challenging tasks such as opinion/modality identification. Unfortunately, the latter goals exceed the ability of the traditional bag-of-word representation approach, and a richer, more structural representation is required. Accordingly, learning algorithms must be created that can handle the structures observed in texts. In this paper, we propose a Boosting algorithm that captures sub-structures embedded in texts. The proposal consists of i) decision stumps that use subtrees as features and ii) the Boosting algorithm which employs the subtree-based decision stumps as weak learners. We also discuss the relation between our algorithm and SVMs with tree kernel. Two experiments on opinion/modality classification confirm that subtree features are important.</Paragraph>
  </Section>
class="xml-element"></Paper>