arXiv Statistics ML

Intrinsic Information-Theoretic Analysis of ReLU Nets

arXiv:2610. 36864v1 Announce Type: new Abstract: Mutual information (MI) is fundamental to representation-learning analysis in deep networks, but in high dimensions MI estimators depend on hyperparameters whose bias often dominates the signal.

arXiv Machine Learning
Aug 26

Multi-Source Complex Network Reconstruction via Wasserstein Distributionally Robust Optimization and Algorithm Unrolling

The paper introduces MS‑WDRO, a multi‑source Wasserstein distributionally robust optimization framework for reconstructing complex network topologies from scarce target‑domain data and abundant heterogeneous source data. It fuses sources via a weighted Wasserstein barycenter, builds an ambiguity set around it, and solves a regularized Laplacian estimator using a provably convergent ADMM scheme. The authors provide finite‑sample guarantees, demonstrate that naive aggregation is suboptimal, and show through experiments on synthetic data and the ABIDE I neuroimaging dataset that MS‑WDRO outperforms seven baselines in graph recovery, sample efficiency, and diagnostic utility, especially when target samples are limited.

By Chuansen Peng, Yifan Xia, Jinshan Zhong, Xiaojing Shen
arXiv Machine Learning
Oct 28

The Geometry of Limits in ReLU Function Spaces

The paper investigates the geometry and closure properties of function spaces realized by ReLU neural networks with fixed architecture. It proves that the minimal number of convex pieces in continuous piecewise-linear functions is lower semicontinuous under pointwise convergence, and uses this to show that shallow scalar ReLU realization spaces are closed in the weighted supremum norm, while providing a counterexample that demonstrates non-closedness for a specific architecture. The work also characterizes the role of a blow‑up residue in non‑closedness and offers new geometric and functional‑analytic tools for analyzing ReLU realization spaces.

By Kathryn A. Lindsey
arXiv Machine Learning
Sep 24

Minimal-Norm Univariate Two-Layer ReLU Classification: Exact Solutions and Global Optimality with Skip Connections

The paper investigates minimal‑norm interpolation and λ2‑regularized logistic‑loss minimization for binary classification using univariate two‑layer ReLU networks. It provides exact geometric characterizations of optimal classifiers, showing that unpenalized hidden‑layer biases yield continuous piecewise‑affine functions that tightly follow label switches, while penalized biases produce a unique, sparsest classifier with a single kink per same‑label segment. Adding a free affine skip connection does not change these function‑space solutions but guarantees that every KKT point becomes globally optimal, eliminating suboptimal KKT points that can arise without the skip connection.

By Karolina Drabik, Ben Lewis, Antoni Puch, Etienne Boursier, Piotr Hofman, Matthias Englert, Ranko Lazi\'c