Higher-order Lexical Semantic Models for Non-factoid Answer Reranking

  title={Higher-order Lexical Semantic Models for Non-factoid Answer Reranking},
  author={Daniel Fried and Peter Alexander Jansen and Gus Hahn-Powell and Mihai Surdeanu and Peter Clark},
  journal={Transactions of the Association for Computational Linguistics},
Lexical semantic models provide robust performance for question answering, but, in general, can only capitalize on direct evidence seen during training. For example, monolingual alignment models acquire term alignment probabilities from semi-structured data such as question-answer pairs; neural network language models learn term embeddings from unstructured text. All this knowledge is then used to estimate the semantic similarity between question and answer candidates. We introduce a higher… 

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