Distributionally Robust Statistical Verification with Imprecise Neural Networks
Souradeep Dutta, Michele Caprio, Vivian Lin, Matthew Cleaveland, Kuk Jin Jang, Ivan Ruchkin, Oleg Sokolsky, Insup Lee
TL;DR
The paper tackles the challenge of providing guarantees for high-dimensional autonomous systems under distributional uncertainty. It introduces distributionally robust statistical verification using Imprecise Neural Networks (INN) to quantify uncertainty and a Sherlock-based active-learning loop to explore input regions efficiently. By constructing an α-contaminated distribution family 𝒫 and deriving a worst-case lower bound Φ^l, the authors prove guarantees that hold across all distributions in 𝒫 with probability at least 1 − 1/λ. Empirically, the approach scales to complex Mujoco control tasks and exhibits robustness to distribution shift, outperforming standard conformal prediction in shifted settings. The framework offers a practical, provable pathway for pre-deployment validation and online monitoring of high-dimensional autonomous systems.
Abstract
A particularly challenging problem in AI safety is providing guarantees on the behavior of high-dimensional autonomous systems. Verification approaches centered around reachability analysis fail to scale, and purely statistical approaches are constrained by the distributional assumptions about the sampling process. Instead, we pose a distributionally robust version of the statistical verification problem for black-box systems, where our performance guarantees hold over a large family of distributions. This paper proposes a novel approach based on uncertainty quantification using concepts from imprecise probabilities. A central piece of our approach is an ensemble technique called Imprecise Neural Networks, which provides the uncertainty quantification. Additionally, we solve the allied problem of exploring the input set using active learning. The active learning uses an exhaustive neural-network verification tool Sherlock to collect samples. An evaluation on multiple physical simulators in the openAI gym Mujoco environments with reinforcement-learned controllers demonstrates that our approach can provide useful and scalable guarantees for high-dimensional systems.
