A Polynomial-Time Dynamic Oracle for Non-Projective Dependency Parsing
نویسندگان
چکیده
The introduction of dynamic oracles has considerably improved the accuracy of greedy transition-based dependency parsers, without sacrificing parsing efficiency. However, this enhancement is limited to projective parsing, and dynamic oracles have not yet been implemented for parsers supporting non-projectivity. In this paper we introduce the first such oracle, for a non-projective parser based on Attardi’s parser. We show that training with this oracle improves parsing accuracy over a conventional (static) oracle on a wide range of datasets.
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