Experiments in Passage Selection and Answer Identification for Question Answering

  • Horacio Saggion
  • Robert Gaizauskas
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4139)


Question Answering (QA) aims at providing users with short text units that answer specific, well-formed natural language questions. A two stage architecture is widely adopted for this task consisting of a document retrieval step followed by an answer extraction step. In such an approach two main problems need to be addressed to reduce the search space: better selecting answer bearing passages in the document retrieval step and better pinpointing answers in the answer extraction step. We investigate the effect of word-based and linguistic-based features for the identification of answer-bearing sentences and answer candidates in a QA system and show that both play a significant role.


Question Answering Binary Predicate Question Answering System Answer Candidate Stage Architecture 
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-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Horacio Saggion
    • 1
  • Robert Gaizauskas
    • 1
  1. 1.Department of Computer ScienceUniversity of SheffieldSheffieldUnited Kingdom

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