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Cited by 3,008

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Accurate unlexicalized parsing

Open access
Klein, Dan, Manning, Christopher D.·2003·Proceedings of the 41st Annual Meeting on Association for Computational Linguistics - ACL '03

Abstract

We demonstrate that an unlexicalized PCFG can parse much more accurately than previously shown, by making use of simple, linguistically motivated state splits, which break down false independence assumptions latent in a vanilla treebank grammar. Indeed, its performance of 86.36% (LP/LR F1) is better than that of early lexicalized PCFG models, and surprisingly close to the current state-of-the-art. This result has potential uses beyond establishing a strong lower bound on the maximum possible accuracy of unlexicalized models: an unlexicalized PCFG is much more compact, easier to replicate, and easier to interpret than more complex lexical models, and the parsing algorithms are simpler, more widely understood, of lower asymptotic complexity, and easier to optimize.

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Metadata

Authors
Klein, D., & Manning, C. D.
Venue
Proceedings of the 41st Annual Meeting on Association for Computational Linguistics - ACL '03
Published
2003
Volume
1
Pages
423-430
OpenAlex
W2097606805
Cited by
3,008
References
1
FWCI
31.18
Type
conference paper
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Accurate unlexicalized parsing. https://app.cochat.ai/papers/10.3115/1075096.1075150
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Klein, D., & Manning, C. D. (2003). Accurate unlexicalized parsing. Proceedings of the 41st Annual Meeting on Association for Computational Linguistics - ACL '03. https://doi.org/10.3115/1075096.1075150

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.