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Discrete Markov random fields are undirected graphical models that capture complex conditional dependencies between discrete variables. Conducting exact posterior inference in these models is often computationally challenging because…

Methodology · Statistics 2026-03-10 Giuseppe Arena , Maarten Marsman

Random sampling is a fundamental tool in modern machine learning and numerical linear algebra for reducing the computational cost of large-scale matrix problems. Existing analyses, however, rely primarily on subspace embedding guarantees,…

Numerical Analysis · Mathematics 2026-05-26 Chengmei Niu , Sachin Garg , Michał Dereziński , Zhenyu Liao

This paper is devoted to the problem of sampling Gaussian fields in high dimension. Solutions exist for two specific structures of inverse covariance : sparse and circulant. The proposed approach is valid in a more general case and…

Computation · Statistics 2011-05-31 F. Orieux , O. Féron , J. -F. Giovannelli

Compressed sensing allows perfect recovery of sparse signals (or signals sparse in some basis) using only a small number of random measurements. Existing results in compressed sensing literature have focused on characterizing the achievable…

Information Theory · Computer Science 2015-05-18 Dmitry Malioutov , Sujay Sanghavi , Alan Willsky

The compressed sensing (CS) framework leverages the sparsity of MR images to reconstruct from undersampled acquisitions. CS reconstructions involve one or more regularization parameters that weigh sparsity in transform domains against…

For a tall $n\times d$ matrix $A$ and a random $m\times n$ sketching matrix $S$, the sketched estimate of the inverse covariance matrix $(A^\top A)^{-1}$ is typically biased: $E[(\tilde A^\top\tilde A)^{-1}]\ne(A^\top A)^{-1}$, where…

Data Structures and Algorithms · Computer Science 2021-07-13 Michał Dereziński , Zhenyu Liao , Edgar Dobriban , Michael W. Mahoney

Many key problems in machine learning and data science are routinely modeled as optimization problems and solved via optimization algorithms. With the increase of the volume of data and the size and complexity of the statistical models used…

Optimization and Control · Mathematics 2020-08-28 Filip Hanzely

Models based on approximation capabilities have recently been studied in the context of Optimal Recovery. These models, however, are not compatible with overparametrization, since model- and data-consistent functions could then be…

Optimization and Control · Mathematics 2020-04-02 Simon Foucart

A wide variety of problems in machine learning, including exemplar clustering, document summarization, and sensor placement, can be cast as constrained submodular maximization problems. Unfortunately, the resulting submodular optimization…

Machine Learning · Computer Science 2015-04-23 Rafael da Ponte Barbosa , Alina Ene , Huy L. Nguyen , Justin Ward

Deep neural networks (DNN) have been used to model nonlinear relations between physical quantities. Those DNNs are embedded in physical systems described by partial differential equations (PDE) and trained by minimizing a loss function that…

Numerical Analysis · Mathematics 2020-02-26 Kailai Xu , Eric Darve

Recovering scene color from images captured in scattering media is a fundamental inverse problem in optical imaging. Yet the problem is intrinsically ill-posed as multiple solutions can explain the same observation, and prediction error…

Computer Vision and Pattern Recognition · Computer Science 2026-05-06 Grigory Solomatov , Derya Akkaynak

We propose a fast and scalable optimization method to solve chance or probabilistic constrained optimization problems governed by partial differential equations (PDEs) with high-dimensional random parameters. To address the critical…

Optimization and Control · Mathematics 2020-11-20 Peng Chen , Omar Ghattas

In this letter, we consider a problem of reconstructing an unknown discrete signal taking values in a finite alphabet from incomplete linear measurements. The difficulty of this problem is that the computational complexity of the…

Information Theory · Computer Science 2015-03-19 Masaaki Nagahara

Complex networks theory has commonly been used for modelling and understanding the interactions taking place between the elements composing complex systems. More recently, the use of generative models has gained momentum, as they allow…

Physics and Society · Physics 2016-05-19 Massimiliano Zanin , Marco Correia , Pedro A. C. Sousa , Jorge Cruz

Neural networks have emerged as effective tools for solving ill-posed inverse problems. In many scientific applications, however, observational training data are insufficient, and learned inverse operators must instead be trained on…

Numerical Analysis · Mathematics 2026-05-26 Sandra R. Babyale , Jodi Mead

In this paper we analyze approximation and recovery properties with respect to systems satisfying universal sampling discretization property and a special incoherence property. We apply a powerful nonlinear approximation method -- the Weak…

Numerical Analysis · Mathematics 2024-01-02 V. Temlyakov

The vast majority of work in self-supervised learning, both theoretical and empirical (though mostly the latter), have largely focused on recovering good features for downstream tasks, with the definition of "good" often being intricately…

Machine Learning · Computer Science 2022-02-21 Bingbin Liu , Daniel Hsu , Pradeep Ravikumar , Andrej Risteski

The problem of high-dimensional and large-scale representation of visual data is addressed from an unsupervised learning perspective. The emphasis is put on discrete representations, where the description length can be measured in bits and…

Machine Learning · Computer Science 2019-01-25 Sohrab Ferdowsi

We investigate the recovery of structures from large-area, low dose exposures that distribute the dose over many identical copies of an object. The reconstruction is done via a maximum likelihood approach that does neither require to…

Materials Science · Physics 2018-03-28 C. Kramberger , J. C. Meyer

We present a method for the reconstruction of networks, based on the order of nodes visited by a stochastic branching process. Our algorithm reconstructs a network of minimal size that ensures consistency with the data. Crucially, we show…

Data Structures and Algorithms · Computer Science 2010-06-07 Nick Fyson , Tijl De Bie , Nello Cristianini
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