Contrasting objective functions for CYK chart decoding

نویسندگان

  • Aaron Dunlop
  • Brian Roark
چکیده

Context-free inference is a standard part of many NLP pipelines. Most approaches use a variant of the CYK dynamic programming algorithm to populate a chart structure with predicted nonterminals over each span. We can extract a parse tree from this chart in several ways. In this work, we compare two commonly-used decoding approaches (Viterbi and max-rule) with a minimum-bayes-risk (MBR) method which has not been widely used. We find that the latter approach is competitive with and in some cases superior to the standard decoding methods.

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تاریخ انتشار 2012