activity
20172026
most citedHandling correlated and repeated measurements with the smoothed multivariate square-root Lasso

17 citations · 75 across the 23 of their papers we have counts for

collaborators

26 papers

cs.CV2026

Principled MAP estimation for inverse problems: bridging the gap between convergence and performance

Alexandre Lagier, Valentine Tosel, Anne Gagneux +2

Pretrained denoisers provide a powerful way to incorporate image priors into restoration algorithms. Plug-and-Play and RED approaches exploit fixed-noise-level denoisers within fir…

cs.LG2026

Beyond the Manifold Hypothesis: Hybrid Spectral Parameterizations for Flow Matching

Ségolène Martin, Anne Gagneux, Quentin Bertrand +2

Flow matching and diffusion can be trained to predict different quantities, most commonly the data , the source noise , or the velocity~. Although theoretically equiva…

cs.CV2026

Training Flow Matching: The Role of Weighting and Parameterization

Anne Gagneux, Ségolène Martin, Rémi Gribonval +1

We study the training objectives of denoising-based generative models, with a particular focus on loss weighting and output parameterization, including noise-, clean image-, and ve…

stat.CO2025

Efficient Solvers for SLOPE in R, Python, Julia, and C++

Johan Larsson, Malgorzata Bogdan, Krystyna Grzesiak +2

We present a suite of packages in R, Python, Julia, and C++ that efficiently solve the Sorted L-One Penalized Estimation (SLOPE) problem. The packages feature a highly efficient hy…

cs.CV2025

The Generation Phases of Flow Matching: a Denoising Perspective

Anne Gagneux, Ségolène Martin, Rémi Gribonval +1

Flow matching has achieved remarkable success, yet the factors influencing the quality of its generation process remain poorly understood. In this work, we adopt a denoising perspe…

math.OC2025

Proximal Operators of Sorted Nonconvex Penalties

Anne Gagneux, Mathurin Massias, Emmanuel Soubies

This work studies the problem of sparse signal recovery with automatic grouping of variables. To this end, we investigate sorted nonsmooth penalties as a regularization approach fo…

eess.IV2025

DeepInverse: A Python package for solving imaging inverse problems with deep learning

Julián Tachella, Matthieu Terris, Samuel Hurault +24

DeepInverse is an open-source PyTorch-based library for solving imaging inverse problems. The library covers all crucial steps in image reconstruction from the efficient implementa…

cs.LG2025

On the Closed-Form of Flow Matching: Generalization Does Not Arise from Target Stochasticity

Quentin Bertrand, Anne Gagneux, Mathurin Massias +1

Modern deep generative models can now produce high-quality synthetic samples that are often indistinguishable from real training data. A growing body of research aims to understand…

cs.LG2025

Convexity in ReLU Neural Networks: beyond ICNNs?

Anne Gagneux, Mathurin Massias, Emmanuel Soubies +1

Convex functions and their gradients play a critical role in mathematical imaging, from proximal optimization to Optimal Transport. The successes of deep learning has led many to u…

cs.LG2024★ 1 cited

Schur's Positive-Definite Network: Deep Learning in the SPD cone with structure

Can Pouliquen, Mathurin Massias, Titouan Vayer

Estimating matrices in the symmetric positive-definite (SPD) cone is of interest for many applications ranging from computer vision to graph learning. While there exist various con…

cs.LG2023★ 1 cited

Implicit Differentiation for Hyperparameter Tuning the Weighted Graphical Lasso

Can Pouliquen, Paulo Gonçalves, Mathurin Massias +1

We provide a framework and algorithm for tuning the hyperparameters of the Graphical Lasso via a bilevel optimization problem solved with a first-order method. In particular, we de…

math.OC2022

Coordinate Descent for SLOPE

Johan Larsson, Quentin Klopfenstein, Mathurin Massias +1

The lasso is the most famous sparse regression and feature selection method. One reason for its popularity is the speed at which the underlying optimization problem can be solved.…

cs.LG2022★ 9 cited

Benchopt: Reproducible, efficient and collaborative optimization benchmarks

Thomas Moreau, Mathurin Massias, Alexandre Gramfort +18

Numerical validation is at the core of machine learning research as it allows to assess the actual impact of new methods, and to confirm the agreement between theory and practice.…

stat.ML2022

Beyond L1: Faster and Better Sparse Models with skglm

Quentin Bertrand, Quentin Klopfenstein, Pierre-Antoine Bannier +2

We propose a new fast algorithm to estimate any sparse generalized linear model with convex or non-convex separable penalties. Our algorithm is able to solve problems with millions…

math.OC2022

Iterative regularization for low complexity regularizers

Cesare Molinari, Mathurin Massias, Lorenzo Rosasco +1

Iterative regularization exploits the implicit bias of an optimization algorithm to regularize ill-posed problems. Constructing algorithms with such built-in regularization mechani…

stat.ML2021★ 3 cited

Implicit differentiation for fast hyperparameter selection in non-smooth convex learning

Quentin Bertrand, Quentin Klopfenstein, Mathurin Massias +4

Finding the optimal hyperparameters of a model can be cast as a bilevel optimization problem, typically solved using zero-order techniques. In this work we study first-order method…

stat.ML2020★ 1 cited

Anderson acceleration of coordinate descent

Quentin Bertrand, Mathurin Massias

Acceleration of first order methods is mainly obtained via inertial techniques à la Nesterov, or via nonlinear extrapolation. The latter has known a recent surge of interest, with…

stat.ML2020★ 2 cited

Iterative regularization for convex regularizers

Cesare Molinari, Mathurin Massias, Lorenzo Rosasco +1

We study iterative regularization for linear models, when the bias is convex but not necessarily strongly convex. We characterize the stability properties of a primal-dual gradient…

math.PR2020★ 4 cited

Dimension-free convergence rates for gradient Langevin dynamics in RKHS

Boris Muzellec, Kanji Sato, Mathurin Massias +1

Gradient Langevin dynamics (GLD) and stochastic GLD (SGLD) have attracted considerable attention lately, as a way to provide convergence guarantees in a non-convex setting. However…

stat.ML2020★ 3 cited

Support recovery and sup-norm convergence rates for sparse pivotal estimation

Mathurin Massias, Quentin Bertrand, Alexandre Gramfort +1

In high dimensional sparse regression, pivotal estimators are estimators for which the optimal regularization parameter is independent of the noise level. The canonical pivotal est…

stat.ML2019★ 8 cited

Dual Extrapolation for Sparse Generalized Linear Models

Mathurin Massias, Samuel Vaiter, Alexandre Gramfort +1

Generalized Linear Models (GLM) form a wide class of regression and classification models, where prediction is a function of a linear combination of the input variables. For statis…

stat.ML2019★ 4 cited

Learning step sizes for unfolded sparse coding

Pierre Ablin, Thomas Moreau, Mathurin Massias +1

Sparse coding is typically solved by iterative optimization techniques, such as the Iterative Shrinkage-Thresholding Algorithm (ISTA). Unfolding and learning weights of ISTA using…

stat.ML2019★ 17 cited

Handling correlated and repeated measurements with the smoothed multivariate square-root Lasso

Quentin Bertrand, Mathurin Massias, Alexandre Gramfort +1

Sparsity promoting norms are frequently used in high dimensional regression. A limitation of such Lasso-type estimators is that the optimal regularization parameter depends on the…

stat.ML2018★ 2 cited

Celer: a Fast Solver for the Lasso with Dual Extrapolation

Mathurin Massias, Alexandre Gramfort, Joseph Salmon

Convex sparsity-inducing regularizations are ubiquitous in high-dimensional machine learning, but solving the resulting optimization problems can be slow. To accelerate solvers, st…