Improving Classifier Robustness through Active Generative Counterfactual Data Augmentation

Ananth Balashankar, Xuezhi Wang, Yao Qin, Ben Packer, Nithum Thain, Ed Chi, Jilin Chen, Alex Beutel


Abstract
Counterfactual Data Augmentation (CDA) is a commonly used technique for improving robustness in natural language classifiers. However, one fundamental challenge is how to discover meaningful counterfactuals and efficiently label them, with minimal human labeling cost. Most existing methods either completely rely on human-annotated labels, an expensive process which limits the scale of counterfactual data, or implicitly assume label invariance, which may mislead the model with incorrect labels. In this paper, we present a novel framework that utilizes counterfactual generative models to generate a large number of diverse counterfactuals by actively sampling from regions of uncertainty, and then automatically label them with a learned auxiliary classifier. Our key insight is that we can more correctly label the generated counterfactuals by training a pairwise classifier that interpolates the relationship between the original example and the counterfactual. We demonstrate that with a small amount of human-annotated counterfactual data (10%), we can generate a counterfactual augmentation dataset with learned labels, that provides an 18-20% improvement in robustness and a 14-21% reduction in errors on 6 out-of-domain datasets, comparable to that of a fully human-annotated counterfactual dataset for both sentiment classification and question paraphrase tasks.
Anthology ID:
2023.findings-emnlp.10
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2023
Month:
December
Year:
2023
Address:
Singapore
Editors:
Houda Bouamor, Juan Pino, Kalika Bali
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
127–139
Language:
URL:
https://aclanthology.org/2023.findings-emnlp.10
DOI:
10.18653/v1/2023.findings-emnlp.10
Bibkey:
Cite (ACL):
Ananth Balashankar, Xuezhi Wang, Yao Qin, Ben Packer, Nithum Thain, Ed Chi, Jilin Chen, and Alex Beutel. 2023. Improving Classifier Robustness through Active Generative Counterfactual Data Augmentation. In Findings of the Association for Computational Linguistics: EMNLP 2023, pages 127–139, Singapore. Association for Computational Linguistics.
Cite (Informal):
Improving Classifier Robustness through Active Generative Counterfactual Data Augmentation (Balashankar et al., Findings 2023)
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PDF:
https://aclanthology.org/2023.findings-emnlp.10.pdf