activity
20242026
collaborators

11 papers

cs.LG2026

Refined Analysis of Entropy-Regularized Actor-Critic

Safwan Labbi, Paul Mangold, Daniil Tiapkin +1

In this paper, we study the role of the critic in actor--critic for entropy-regularized, finite, discounted environments. We establish that, when the critic is exact, using the lat…

stat.ML2026

Gaussian Approximation and Multiplier Bootstrap for Federated Linear Stochastic Approximation

Ilya Levin, Maksim Shuklin, Eric Moulines +2

In this paper, we establish Berry-Esseen-type bounds for federated linear stochastic approximation (LSA). Our results provide the first federated Gaussian approximations for LSA th…

cs.LG2026

Tight Analysis of Decentralized SGD: A Markov Chain Perspective

Lucas Versini, Paul Mangold, Aymeric Dieuleveut

We propose a novel analysis of the Decentralized Stochastic Gradient Descent (DSGD) algorithm with constant step size, interpreting the iterates of the algorithm as a Markov chain.…

cs.LG2026

Beyond Softmax and Entropy: Convergence Rates of Policy Gradients with f-SoftArgmax Parameterization & Coupled Regularization

Safwan Labbi, Daniil Tiapkin, Paul Mangold +1

Policy gradient methods are known to be highly sensitive to the choice of policy parameterization. In particular, the widely used softmax parameterization can induce ill-conditione…

cs.LG2025

Convergence Guarantees for Federated SARSA with Local Training and Heterogeneous Agents

Paul Mangold, Eloïse Berthier, Eric Moulines

We present a novel theoretical analysis of Federated SARSA (FedSARSA) with linear function approximation and local training. We establish convergence guarantees for FedSARSA in the…

cs.LG2025

On Global Convergence Rates for Federated Softmax Policy Gradient under Heterogeneous Environments

Safwan Labbi, Paul Mangold, Daniil Tiapkin +1

We provide global convergence rates for vanilla and entropy-regularized federated softmax stochastic policy gradient (FedPG) with local training. We show that FedPG converges to a…

stat.ML2025

Scaffold with Stochastic Gradients: New Analysis with Linear Speed-Up

Paul Mangold, Alain Durmus, Aymeric Dieuleveut +1

This paper proposes a novel analysis for the Scaffold algorithm, a popular method for dealing with data heterogeneity in federated learning. While its convergence in deterministic…

stat.ML2024

Refined Analysis of Federated Averaging and Federated Richardson-Romberg

Paul Mangold, Alain Durmus, Aymeric Dieuleveut +2

In this paper, we present a novel analysis of \FedAvg with constant step size, relying on the Markov property of the underlying process. We demonstrate that the global iterates of…

cs.LG2024

Federated UCBVI: Communication-Efficient Federated Regret Minimization with Heterogeneous Agents

Safwan Labbi, Daniil Tiapkin, Lorenzo Mancini +2

In this paper, we present the Federated Upper Confidence Bound Value Iteration algorithm (), a novel extension of the algorithm (Azar et al., 2…

eess.SP2024

Joint Channel Selection using FedDRL in V2X

Lorenzo Mancini, Safwan Labbi, Karim Abed Meraim +4

Vehicle-to-everything (V2X) communication technology is revolutionizing transportation by enabling interactions between vehicles, devices, and infrastructures. This connectivity en…

stat.ML2024

SCAFFLSA: Taming Heterogeneity in Federated Linear Stochastic Approximation and TD Learning

Paul Mangold, Sergey Samsonov, Safwan Labbi +4

In this paper, we analyze the sample and communication complexity of the federated linear stochastic approximation (FedLSA) algorithm. We explicitly quantify the effects of local t…