arXiv Machine Learning

Efficient Support Recovery of Mixtures of Sparse Linear Classifiers with Fewer Measurements

arXiv Machine Learning
Aug 31

Towards a mathematical theory of superposition

The paper develops a mathematical theory of superposition in neural networks using frame theory and compressed sensing. It shows that a sparse binary vector of active features can be encoded by an overcomplete dictionary and recovered via a ReLU operation with a suitable bias. The authors prove recovery theorems for both random-support and worst-case support settings, providing high-probability guarantees for low-coherence dictionaries and a sharp criterion for sparsity levels, with explicit results for Gaussian random matrices and equiangular tight frames.

By Michael I. Ivanitskiy, John Jasper, Emily J. King, Dustin G. Mixon
arXiv Computer Vision
Sep 21

Classification-oriented adaptive sensing via posterior sampling

The paper proposes a classification-oriented adaptive sensing method that uses posterior sampling from diffusion models. It leverages the closed-form posterior covariance of a class-conditional Gaussian mixture model to separate within-class and between-class uncertainty, estimating these terms from diffusion posterior samples via calibrated soft classifier outputs. Experiments on MNIST and CIFAR-10 demonstrate that this approach can achieve better classification accuracy for a given measurement cost compared to reconstruction-oriented methods, while also quantifying the associated reconstruction quality.

By Andriy Enttsel, Maxime Rousselot, Vincent Corlay