Tokenization Consistency Matters for Generative Models on Extractive NLP Tasks

  title={Tokenization Consistency Matters for Generative Models on Extractive NLP Tasks},
  author={Kaiser Sun and Peng Qi and Yuhao Zhang and Lan Liu and William Yang Wang and Zhiheng Huang},
Generative models have been widely applied to solve extractive tasks, where parts of the input is extracted to form the desired output, and achieved significant success. For example, in extractive question answering (QA), generative models have constantly yielded state-of-the-art results. In this work, we identify the issue of tokenization inconsistency that is commonly neglected in training these models. This issue damages the extractive nature of these tasks after the input and output are… 



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