ELF: Federated Langevin Algorithms with Primal, Dual and Bidirectional Compression


Avetik Karagulyan (Université Paris-Saclay, CNRS, CentraleSupélec, L2S)
February 07, 2025 — 11:00 — "new L2S location (IBM building), Room Hopper (Third floor)" (and Teams)

Abstract

Federated sampling algorithms have recently gained great popularity in the community of machine learning and statistics. This paper studies variants of such algorithms called Error Feedback Langevin algorithms (ELF). In particular, we analyze the combinations of EF21 and EF21-P with the federated Langevin Monte-Carlo. We propose three algorithms: P-ELF, D-ELF, and B-ELF that use, respectively, primal, dual, and bidirectional compressors. We analyze the proposed methods under Log-Sobolev inequality and provide non-asymptotic convergence guarantees.

Bio

I am a Research Scientist at CNRS/L2S. Previously, I was a PostDoctoral fellow at KAUST in the team of professor Peter Richtárik. I have defended my thesis at Center of Research in Economics and STatistics (CREST), Paris under the supervision of professor Arnak Dalalyan. In 2018, I received my MSc Mathematics, Vision, Learning (MVA) diploma at ENS Paris-Saclay with highest honors (mention “très bien”). I graduated from Yerevan State University’s faculty of Mathematics and Mechanics in 2017 with excellence. My research focuses on the study of different methods of sampling and their connections to optimization.