GeneSis: A Generative Approach to Substitutes in Context

Caterina Lacerra, Rocco Tripodi, Roberto Navigli


Abstract
The lexical substitution task aims at generating a list of suitable replacements for a target word in context, ideally keeping the meaning of the modified text unchanged. While its usage has increased in recent years, the paucity of annotated data prevents the finetuning of neural models on the task, hindering the full fruition of recently introduced powerful architectures such as language models. Furthermore, lexical substitution is usually evaluated in a framework that is strictly bound to a limited vocabulary, making it impossible to credit appropriate, but out-of-vocabulary, substitutes. To assess these issues, we proposed GeneSis (Generating Substitutes in contexts), the first generative approach to lexical substitution. Thanks to a seq2seq model, we generate substitutes for a word according to the context it appears in, attaining state-of-the-art results on different benchmarks. Moreover, our approach allows silver data to be produced for further improving the performances of lexical substitution systems. Along with an extensive analysis of GeneSis results, we also present a human evaluation of the generated substitutes in order to assess their quality. We release the fine-tuned models, the generated datasets, and the code to reproduce the experiments at https://github.com/SapienzaNLP/genesis.
Anthology ID:
2021.emnlp-main.844
Volume:
Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2021
Address:
Online and Punta Cana, Dominican Republic
Editors:
Marie-Francine Moens, Xuanjing Huang, Lucia Specia, Scott Wen-tau Yih
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
10810–10823
Language:
URL:
https://aclanthology.org/2021.emnlp-main.844
DOI:
10.18653/v1/2021.emnlp-main.844
Bibkey:
Cite (ACL):
Caterina Lacerra, Rocco Tripodi, and Roberto Navigli. 2021. GeneSis: A Generative Approach to Substitutes in Context. In Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing, pages 10810–10823, Online and Punta Cana, Dominican Republic. Association for Computational Linguistics.
Cite (Informal):
GeneSis: A Generative Approach to Substitutes in Context (Lacerra et al., EMNLP 2021)
Copy Citation:
PDF:
https://preview.aclanthology.org/naacl24-info/2021.emnlp-main.844.pdf
Video:
 https://preview.aclanthology.org/naacl24-info/2021.emnlp-main.844.mp4
Code
 sapienzanlp/genesis