no code implementations • 14 Mar 2024 • Simon Briend, Christophe Giraud, Gábor Lugosi, Déborah Sulem
This paper studies the problem of estimating the order of arrival of the vertices in a random recursive tree.
no code implementations • 31 May 2023 • Evgenii Chzhen, Christophe Giraud, Gilles Stoltz
We consider the problem of minimizing a convex function over a closed convex set, with Projected Gradient Descent (PGD).
no code implementations • 18 Mar 2022 • Solenne Gaucher, Alexandra Carpentier, Christophe Giraud
We also derive gap-dependent upper bounds on the regret, and matching lower bounds for some problem instance. Interestingly, these results reveal a transition between a regime where the problem is as difficult as its unbiased counterpart, and a regime where it can be much harder.
1 code implementation • 29 Oct 2021 • Karl Hajjar, Lénaïc Chizat, Christophe Giraud
For two-layer neural networks, it has been understood via these asymptotics that the nature of the trained model radically changes depending on the scale of the initial random weights, ranging from a kernel regime (for large initial variance) to a feature learning regime (for small initial variance).
no code implementations • 6 Aug 2021 • Christophe Giraud, Yann Issartel, Nicolas Verzelen
We consider the problem of estimating latent positions in a one-dimensional torus from pairwise affinities.
no code implementations • NeurIPS 2021 • Evgenii Chzhen, Christophe Giraud, Gilles Stoltz
We provide a setting and a general approach to fair online learning with stochastic sensitive and non-sensitive contexts.
no code implementations • 17 May 2019 • Christophe Giraud, Yann Issartel, Luc Lehéricy, Matthieu Lerasle
This paper shows that sublinear regret is achievable in the case where the graph is generated according to a Stochastic Block Model (SBM) with two communities.
no code implementations • 19 Jul 2018 • Christophe Giraud, Nicolas Verzelen
We investigate the clustering performances of the relaxed $K$means in the setting of sub-Gaussian Mixture Model (sGMM) and Stochastic Block Model (SBM).
1 code implementation • 16 Jun 2016 • Florentina Bunea, Christophe Giraud, Martin Royer, Nicolas Verzelen
The problem of variable clustering is that of grouping similar components of a $p$-dimensional vector $X=(X_{1},\ldots, X_{p})$, and estimating these groups from $n$ independent copies of $X$.
Statistics Theory Statistics Theory
1 code implementation • 8 Aug 2015 • Florentina Bunea, Christophe Giraud, Xi Luo, Martin Royer, Nicolas Verzelen
We quantify the difficulty of clustering data generated from a G-block covariance model in terms of cluster proximity, measured with respect to two related, but different, cluster separation metrics.
no code implementations • 27 Apr 2014 • Christophe Giraud, François Roueff, Andres Sanchez-Perez
It is obtained by aggregating a finite number of well chosen predictors, each of them enjoying an optimal minimax convergence rate under specific smoothness conditions on the TVAR coefficients.