Low Anisotropy Sense Retrofitting (LASeR) : Towards Isotropic and Sense Enriched Representations

Geetanjali Bihani, Julia Rayz


Abstract
Contextual word representation models have shown massive improvements on a multitude of NLP tasks, yet their word sense disambiguation capabilities remain poorly explained. To address this gap, we assess whether contextual word representations extracted from deep pretrained language models create distinguishable representations for different senses of a given word. We analyze the representation geometry and find that most layers of deep pretrained language models create highly anisotropic representations, pointing towards the existence of representation degeneration problem in contextual word representations. After accounting for anisotropy, our study further reveals that there is variability in sense learning capabilities across different language models. Finally, we propose LASeR, a ‘Low Anisotropy Sense Retrofitting’ approach that renders off-the-shelf representations isotropic and semantically more meaningful, resolving the representation degeneration problem as a post-processing step, and conducting sense-enrichment of contextualized representations extracted from deep neural language models.
Anthology ID:
2021.deelio-1.9
Volume:
Proceedings of Deep Learning Inside Out (DeeLIO): The 2nd Workshop on Knowledge Extraction and Integration for Deep Learning Architectures
Month:
June
Year:
2021
Address:
Online
Venues:
DeeLIO | NAACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
81–95
Language:
URL:
https://aclanthology.org/2021.deelio-1.9
DOI:
10.18653/v1/2021.deelio-1.9
Bibkey:
Cite (ACL):
Geetanjali Bihani and Julia Rayz. 2021. Low Anisotropy Sense Retrofitting (LASeR) : Towards Isotropic and Sense Enriched Representations. In Proceedings of Deep Learning Inside Out (DeeLIO): The 2nd Workshop on Knowledge Extraction and Integration for Deep Learning Architectures, pages 81–95, Online. Association for Computational Linguistics.
Cite (Informal):
Low Anisotropy Sense Retrofitting (LASeR) : Towards Isotropic and Sense Enriched Representations (Bihani & Rayz, DeeLIO 2021)
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PDF:
https://aclanthology.org/2021.deelio-1.9.pdf
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 2021.deelio-1.9.OptionalSupplementaryData.zip