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20232026
most citedPhase transitions for the existence of unregularized M-estimators in single index models

1 citations · 2 across the 11 of their papers we have counts for

collaborators

12 papers

math.ST2026

Generalization Error Estimation for Primal--Dual Algorithms in Non-Smooth Regression

Kai Tan, Pierre C Bellec

This paper studies trajectory-wise estimation of generalization error for primal--dual algorithms in non-smooth regression. Motivating examples include \(\ell_1\)-penalized least a…

math.ST2025

The Lasso error is bounded iff its active set size is bounded away from n in the proportional regime

Pierre C. Bellec

This note develops an analysis of the Lasso \( \hat b\) in linear models without any sparsity or L1 assumption on the true regression vector, in the proportional regime where dimen…

math.ST2025★ 1 cited

Phase transitions for the existence of unregularized M-estimators in single index models

Takuya Koriyama, Pierre C. Bellec

This paper studies phase transitions for the existence of unregularized M-estimators under proportional asymptotics where the sample size and feature dimension grow proport…

math.ST2025★ 1 cited

Simultaneous analysis of approximate leave-one-out cross-validation and mean-field inference

Pierre C Bellec

Approximate Leave-One-Out Cross-Validation (ALO-CV) is a method that has been proposed to estimate the generalization error of a regularized estimator in the high-dimensional regim…

math.PR2024

Optimizing over iid distributions and the Beat the Average game

Pierre C Bellec, Tobias Fritz

A casino offers the following game. There are three cups each containing a die. You are being told that the dice in the cups are all the same, but possibly nonstandard. For a bet o…

math.ST2024

Estimating Generalization Performance Along the Trajectory of Proximal SGD in Robust Regression

Kai Tan, Pierre C. Bellec

This paper studies the generalization performance of iterates obtained by Gradient Descent (GD), Stochastic Gradient Descent (SGD) and their proximal variants in high-dimensional r…

math.ST2024

Precise Asymptotics of Bagging Regularized M-estimators

Takuya Koriyama, Pratik Patil, Jin-Hong Du +2

We characterize the squared prediction risk of ensemble estimators obtained through subagging (subsample bootstrap aggregating) regularized M-estimators and construct a consistent…

stat.ML2024

Uncertainty quantification for iterative algorithms in linear models with application to early stopping

Pierre C. Bellec, Kai Tan

This paper investigates the iterates $\hbb^1,\dots,\hbb^T$ obtained from iterative algorithms in high-dimensional linear regression problems, in the regime where the feature dimens…

math.ST2024

Asymptotics of resampling without replacement in robust and logistic regression

Pierre C. Bellec, Takuya Koriyama

This paper studies the asymptotics of resampling without replacement in the proportional regime where dimension and sample size are of the same order. For a given dataset $…

math.ST2023

Error estimation and adaptive tuning for unregularized robust M-estimator

Pierre C. Bellec, Takuya Koriyama

We consider unregularized robust M-estimators for linear models under Gaussian design and heavy-tailed noise, in the proportional asymptotics regime where the sample size n and the…

math.ST2023

Existence of solutions to the nonlinear equations characterizing the precise error of M-estimators

Pierre C. Bellec, Takuya Koriyama

Major progress has been made in the previous decade to characterize the asymptotic behavior of regularized M-estimators in high-dimensional regression problems in the proportional…

math.ST2023

Corrected generalized cross-validation for finite ensembles of penalized estimators

Pierre C. Bellec, Jin-Hong Du, Takuya Koriyama +2

Generalized cross-validation (GCV) is a widely-used method for estimating the squared out-of-sample prediction risk that employs a scalar degrees of freedom adjustment (in a multip…