Depth-bounding is effective: Improvements and evaluation of unsupervised PCFG induction (D18-1)
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| Challenge: | Recent attempts to improve grammar induction systems by bounding complexity of the model have not been compared against unbounded induction models. |
| Approach: | They propose to use a Bayesian induction inducer to limit the search space of the model and then sample trees with or without bounding. |
| Outcome: | The proposed model produces trees more accurately than or competitively with state-of-the-art constituency grammar induction models. |
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| Challenge: | Existing models for syntactic acquisition are word-based and do not inspect functional affixes. |
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| Challenge: | Existing studies on visually grounded grammar induction have not evaluated text domains that are different from the training domain. |
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| Challenge: | Existing induction models unable to incorporate semantics and morphology into induction . current models lack a robust model for generating morphologically rich sentences . |
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Boyi Li, Rodolfo Corona, Karttikeya Mangalam, Catherine Chen, Daniel Flaherty, Serge Belongie, Kilian Weinberger, Jitendra Malik, Trevor Darrell, Dan Klein
| Challenge: | Recent studies show multimodal inputs can improve grammar induction, but weak textual baselines are needed for training. |
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Neural Bi-Lexicalized PCFG Induction (2021.acl-long)
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| Challenge: | Neural lexicalized PCFGs make strong independence assumption on the generation of the child word and thus bilexical dependencies are ignored. |
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Improved Latent Tree Induction with Distant Supervision via Span Constraints (2021.emnlp-main)
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Zhiyang Xu, Andrew Drozdov, Jay Yoon Lee, Tim O’Gorman, Subendhu Rongali, Dylan Finkbeiner, Shilpa Suresh, Mohit Iyyer, Andrew McCallum
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Exploiting Syntactic Structure for Better Language Modeling: A Syntactic Distance Approach (2020.acl-main)
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| Challenge: | incorporating syntactic structure into language models has been a challenge since the 1990s. |
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Visually Grounded Compound PCFGs (2020.emnlp-main)
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| Challenge: | Existing work on visual groundings for language understanding has been drawing much attention. |
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