Left-to-Right Dependency Parsing with Pointer Networks
Daniel Fernández-González, Carlos Gómez-Rodríguez
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ReproduceCode
- github.com/danifg/Left2Right-Pointer-ParserOfficialIn paperpytorch★ 0
- github.com/danifg/SyntacticPointerpytorch★ 0
Abstract
We propose a novel transition-based algorithm that straightforwardly parses sentences from left to right by building n attachments, with n being the length of the input sentence. Similarly to the recent stack-pointer parser by Ma et al. (2018), we use the pointer network framework that, given a word, can directly point to a position from the sentence. However, our left-to-right approach is simpler than the original top-down stack-pointer parser (not requiring a stack) and reduces transition sequence length in half, from 2n-1 actions to n. This results in a quadratic non-projective parser that runs twice as fast as the original while achieving the best accuracy to date on the English PTB dataset (96.04% UAS, 94.43% LAS) among fully-supervised single-model dependency parsers, and improves over the former top-down transition system in the majority of languages tested.
Tasks
Benchmark Results
| Dataset | Model | Metric | Claimed | Verified | Status |
|---|---|---|---|---|---|
| Penn Treebank | Left-to-Right Pointer Network | LAS | 94.43 | — | Unverified |