Improving the Certified Robustness of Neural Networks via Consistency Regularization
This work provides an incremental improvement in certified robustness for neural networks, which is important for researchers and practitioners working on provable defenses against adversarial attacks.
The paper addresses the inconsistency in certified robustness constraints between correctly and misclassified examples in neural networks. By introducing a novel consistency regularization term, Misclassification Aware Adversarial Regularization (MAAR), the authors significantly improve certified robustness on CIFAR-10 and MNIST datasets compared to state-of-the-art methods.
A range of defense methods have been proposed to improve the robustness of neural networks on adversarial examples, among which provable defense methods have been demonstrated to be effective to train neural networks that are certifiably robust to the attacker. However, most of these provable defense methods treat all examples equally during training process, which ignore the inconsistent constraint of certified robustness between correctly classified (natural) and misclassified examples. In this paper, we explore this inconsistency caused by misclassified examples and add a novel consistency regularization term to make better use of the misclassified examples. Specifically, we identified that the certified robustness of network can be significantly improved if the constraint of certified robustness on misclassified examples and correctly classified examples is consistent. Motivated by this discovery, we design a new defense regularization term called Misclassification Aware Adversarial Regularization (MAAR), which constrains the output probability distributions of all examples in the certified region of the misclassified example. Experimental results show that our proposed MAAR achieves the best certified robustness and comparable accuracy on CIFAR-10 and MNIST datasets in comparison with several state-of-the-art methods.