arXiv Machine Learning

Distinguishability and Recovery for a Doubly Sparse Spiked Wigner Model

The paper investigates how to distinguish and recover a sparse rank‑one signal in a spiked Wigner model where both the signal and the noise are independently sparse. It introduces a leave‑one‑out quadratic thresholding method that identifies the signal support for sub‑Gaussian noise and bounded spikes, and shows that sign synchronization and spectral refinement can achieve exact or strong recovery for Rademacher spikes. The work also extends to sub‑Gaussian spike priors, provides an explicit trade‑off between signal sparsity, noise sparsity, and computational cost, and establishes recoverability conditions that do not rely on moment assumptions for continuous noise.

arXiv Machine Learning
Jul 14

Demixing Sparse Signals from Nonlinear Observations using Generalized Non-convex Regularization

arXiv:2607. 10618v1 Announce Type: cross Abstract: We consider the recovery of a pair of sparse vectors from a limited number of nonlinear observations of their superposition: $y_i=g(\inner{\ba_i}{\bPhi\bw^\ast+\bPsi\bz^\ast})+e_i$, $i=1,\dots,m$, with $m\ll n$, incoherent orthonormal bases $\bPhi,\bPsi$, a scalar link $g$, and noise $e_i$ that may be heavy-tailed or contaminated.

By Raziyeh Takbiri
arXiv Statistics ML
Sep 24

Rank-One Signal Recovery in Sparse Wishart Noise

arXiv:2609.28163v1 Announce Type: cross Abstract: We study the high-dimensional recovery of a signal vector $\mathbf{x}$ in the presence of sparse Wishart-like noise. We define an $N \times N$ matrix...

By Preben Forer, Urte Adomaityte, Pierpaolo Vivo
arXiv Machine Learning
Aug 20

Inference and Uncertainty Quantification for Streaming $r$-PCA

The paper tackles two key gaps in streaming PCA using Oja's algorithm: it establishes sharp operator‑norm convergence for general‑rank subspaces under sub‑Gaussian data, and it provides distributional inference for the resulting subspace estimator. The authors remove non‑vanishing remainder terms from existing analyses, achieving rates that match minimax bounds in both dense‑tail and sparse‑tail regimes. They further develop a linearization of Oja’s iterates, enabling high‑dimensional Gaussian approximations and an online multiplier bootstrap for practical inference.

By Haoshu Xu, Hongzhe Li