Verifying Generalization in Deep Learning
This addresses the risk of deploying DNN-based systems in mission-critical or variable real-world environments, though it is incremental as it builds on existing verification techniques.
The paper tackles the problem of poor generalization in deep neural networks (DNNs) by proposing a verification-driven methodology to identify decision rules that generalize well to new input domains, showing its usefulness on three deep reinforcement learning benchmarks including an Internet congestion control system.
Deep neural networks (DNNs) are the workhorses of deep learning, which constitutes the state of the art in numerous application domains. However, DNN-based decision rules are notoriously prone to poor generalization, i.e., may prove inadequate on inputs not encountered during training. This limitation poses a significant obstacle to employing deep learning for mission-critical tasks, and also in real-world environments that exhibit high variability. We propose a novel, verification-driven methodology for identifying DNN-based decision rules that generalize well to new input domains. Our approach quantifies generalization to an input domain by the extent to which decisions reached by independently trained DNNs are in agreement for inputs in this domain. We show how, by harnessing the power of DNN verification, our approach can be efficiently and effectively realized. We evaluate our verification-based approach on three deep reinforcement learning (DRL) benchmarks, including a system for Internet congestion control. Our results establish the usefulness of our approach. More broadly, our work puts forth a novel objective for formal verification, with the potential for mitigating the risks associated with deploying DNN-based systems in the wild.