Improved Latent Tree Induction with Distant Supervision via Span Constraints

  title={Improved Latent Tree Induction with Distant Supervision via Span Constraints},
  author={Zhiyang Xu and Andrew Drozdov and Jay Yoon Lee and Timothy J. O'Gorman and Subendhu Rongali and Dylan Finkbeiner and Shilpa Suresh and Mohit Iyyer and Andrew McCallum},
For over thirty years, researchers have developed and analyzed methods for latent tree induction as an approach for unsupervised syntactic parsing. Nonetheless, modern systems still do not perform well enough compared to their supervised counterparts to have any practical use as structural annotation of text. In this work, we present a technique that uses distant supervision in the form of span constraints (i.e. phrase bracketing) to improve performance in unsupervised constituency parsing… 

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