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Hierarchical Entity Typing via Multi-level Learning to Rank

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 نشر من قبل Tongfei Chen
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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We propose a novel method for hierarchical entity classification that embraces ontological structure at both training and during prediction. At training, our novel multi-level learning-to-rank loss compares positive types against negative siblings according to the type tree. During prediction, we define a coarse-to-fine decoder that restricts viable candidates at each level of the ontology based on already predicted parent type(s). We achieve state-of-the-art across multiple datasets, particularly with respect to strict accuracy.



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