- Abstract: We present a new approach to neural network verification based on estimating the proportion of inputs for which a property is violated. Specifically, we estimate the probability of the event that the property is violated under an input model. This permits classic verification as a special case, for which one considers only the question of whether this expectation is exactly zero or not. When the property can be violated, our approach provides an informative notion of how robust the network is, rather than just the conventional assertion that the network is not verifiable. Furthermore, it provides an ability to scale to larger networks than classical formal verification approaches. Key to achieving this is an adaptation of multi-level splitting, a Monte Carlo approach for estimating the probability of rare events, to our statistical verification framework. We demonstrate that our approach is able to emulate existing verification procedures on benchmark problems, while scaling to larger networks and providing reliable additional information in the form of accurate estimates of the violation probability.
- Keywords: neural network verification, multi-level splitting, formal verification
- TL;DR: We introduce a statistical approach to neural network verification that provides an informative notion of how robust a network is, rather than just the conventional binary assertion of whether or not of property is violated.