arXiv Machine Learning By Nawel Arab, Mohammed Nabil El Korso, Isabelle Vin, Pascal Larzabal

Stochastic Expectation Maximization for Robust State-Space Radio Interferometric Imaging

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arXiv:2606. 23944v1 Announce Type: cross Abstract: State--space models provide a flexible framework for analyzing dynamical systems, yet they often rely on Gaussian assumptions that fail to capture heavy-tailed or outlier-prone measurement noise.

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arXiv Machine Learning
Oct 16

Robust Covariance Estimation for Entry-wise Contaminated and Partially Observed Data via Expectation Maximization Algorithm

The paper presents a robust covariance estimation method for data that is both entry-wise contaminated and partially observed. It extends the Student‑t* model by using a stochastic approximation EM algorithm that operates on a reduced latent space, avoiding explicit sampling of latent Gaussian variables while maintaining a likelihood‑based framework. Experiments on synthetic and real sensor data demonstrate that this approach achieves lower Fisher‑Rao error than Gaussian, Student‑t, imputation‑based, and detect‑then‑estimate estimators, especially at moderate to high outlier rates under diffuse contamination.

By Matys Savidan, Mohammed Nabil El Korso
arXiv Machine Learning
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Generative Translation Priors: Bayesian Imaging with Cross-Modality Image Translation

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By Evan Bell, Jiaming Liu, Yifan Chen, Yu Sun