A Unified Matrix-Spectral Framework for Stability and Interpretability in Deep Learning
Ronald Katende
TL;DR
This work introduces a unified matrix-spectral framework for stability and interpretability in deep learning by representing networks through data-dependent matrix operators and aggregating their spectra into a Global Matrix Stability Index $\mathfrak{S}(f_\theta;\mu,\nu)$. It couples forward sensitivity, attribution robustness, NTK conditioning, and curvature into a single spectral scale and adds spectral entropy $H_S$ to capture typical, not just worst-case, sensitivity, yielding refined analytic guarantees and diagnostics. The Canonical Unified Matrix Stability Theorem connects finite $\mathfrak{S}$ to stability properties, while the Spectral Entropy framework (including SERR) links initialization and depth to stability behavior under NTK dynamics. Empirical results on synthetic data, MNIST, CIFAR-10, and CIFAR-100 show that modest spectral regularization improves attribution stability and reduces distributional changes in attributions, even when global spectra change little, providing a practical toolkit for robustness-aware design and training.
Abstract
We develop a unified matrix-spectral framework for analyzing stability and interpretability in deep neural networks. Representing networks as data-dependent products of linear operators reveals spectral quantities governing sensitivity to input perturbations, label noise, and training dynamics. We introduce a Global Matrix Stability Index that aggregates spectral information from Jacobians, parameter gradients, Neural Tangent Kernel operators, and loss Hessians into a single stability scale controlling forward sensitivity, attribution robustness, and optimization conditioning. We further show that spectral entropy refines classical operator-norm bounds by capturing typical, rather than purely worst-case, sensitivity. These quantities yield computable diagnostics and stability-oriented regularization principles. Synthetic experiments and controlled studies on MNIST, CIFAR-10, and CIFAR-100 confirm that modest spectral regularization substantially improves attribution stability even when global spectral summaries change little. The results establish a precise connection between spectral concentration and analytic stability, providing practical guidance for robustness-aware model design and training.
