Improved Tree-to-String Transducer for Machine Translation

نویسندگان

  • Ding Liu
  • Daniel Gildea
چکیده

We propose three enhancements to the treeto-string (TTS) transducer for machine translation: first-level expansion-based normalization for TTS templates, a syntactic alignment framework integrating the insertion of unaligned target words, and subtree-based ngram model addressing the tree decomposition probability. Empirical results show that these methods improve the performance of a TTS transducer based on the standard BLEU4 metric. We also experiment with semantic labels in a TTS transducer, and achieve improvement over our baseline system.

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تاریخ انتشار 2008