Yao Li


2022

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ADDMU: Detection of Far-Boundary Adversarial Examples with Data and Model Uncertainty Estimation
Fan Yin | Yao Li | Cho-Jui Hsieh | Kai-Wei Chang
Proceedings of the 2022 Conference on Empirical Methods in Natural Language Processing

Adversarial Examples Detection (AED) is a crucial defense technique against adversarial attacks and has drawn increasing attention from the Natural Language Processing (NLP) community. Despite the surge of new AED methods, our studies show that existing methods heavily rely on a shortcut to achieve good performance. In other words, current search-based adversarial attacks in NLP stop once model predictions change, and thus most adversarial examples generated by those attacks are located near model decision boundaries. To surpass this shortcut and fairly evaluate AED methods, we propose to test AED methods with Far Boundary (FB) adversarial examples. Existing methods show worse than random guess performance under this scenario. To overcome this limitation, we propose a new technique, ADDMU, adversary detection with data and model uncertainty, which combines two types of uncertainty estimation for both regular and FB adversarial example detection. Our new method outperforms previous methods by 3.6 and 6.0 AUC points under each scenario. Finally, our analysis shows that the two types of uncertainty provided by ADDMU can be leveraged to characterize adversarialexamples and identify the ones that contribute most to model’s robustness in adversarial training.

2011

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Combining Syntactic and Semantic Features by SVM for Unrestricted Coreference Resolution
Huiwei Zhou | Yao Li | Degen Huang | Yan Zhang | Chunlong Wu | Yuansheng Yang
Proceedings of the Fifteenth Conference on Computational Natural Language Learning: Shared Task