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How To Select An Answer String?

  • Abdessamad Echihabi
  • Ulf Hermjakob
  • Eduard Hovy
  • Daniel Marcu
  • Eric Melz
  • Deepak Ravichandran
Part of the Text, Speech and Language Technology book series (TLTB, volume 32)

Given a question Q and a sentence/paragraph SP that is likely to contain the answer to Q, an answer selection module is supposed to select the “exact” answer sub-string A ⊂ SP. We study three distinct approaches to solving this problem: one approach uses algorithms that rely on rich knowledge bases and sophisticated syntactic/semantic processing; one approach uses patterns that are learned in an unsupervised manner from the web, using computational biology-inspired alignment algorithms; and one approach uses statistical noisy-channel algorithms similar to those used in machine translation. We assess the strengths and weaknesses of these three approaches and show how they can be combined using a maximum entropy-based framework.

Keywords

Parse Tree Question Answering Exact Answer Statistical Machine Translation Question Answering System 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer 2008

Authors and Affiliations

  • Abdessamad Echihabi
    • 1
  • Ulf Hermjakob
    • 1
  • Eduard Hovy
    • 1
  • Daniel Marcu
    • 1
  • Eric Melz
    • 1
  • Deepak Ravichandran
    • 1
  1. 1.USC Information Sciences InstituteMarina del ReyUSA

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