• Corpus ID: 14644892

Answer Extraction as Sequence Tagging with Tree Edit Distance

@inproceedings{Yao2013AnswerEA,
  title={Answer Extraction as Sequence Tagging with Tree Edit Distance},
  author={Xuchen Yao and Benjamin Van Durme and Chris Callison-Burch and Peter Clark},
  booktitle={NAACL},
  year={2013}
}
Our goal is to extract answers from preretrieved sentences for Question Answering (QA). We construct a linear-chain Conditional Random Field based on pairs of questions and their possible answer sentences, learning the association between questions and answer types. This casts answer extraction as an answer sequence tagging problem for the first time, where knowledge of shared structure between question and source sentence is incorporated through features based on Tree Edit Distance (TED). Our… 

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