activity
20242026
collaborators

7 papers

cs.LG2026

Decentralized Parameter-Free Online Learning with Compressed Gossip

Tomas Ortega, Hamid Jafarkhani

We study decentralized online convex optimization when agents communicate over a graph and messages may be compressed. Classical decentralized online methods typically require lear…

cs.LG2026

Communication Compression for Distributed Learning with Aggregate and Server-Guided Feedback

Tomas Ortega, Chun-Yin Huang, Xiaoxiao Li +1

Distributed learning, particularly Federated Learning (FL), faces a significant bottleneck in the communication cost, particularly the uplink transmission of client-to-server updat…

cs.LG2025

Decentralized Parameter-Free Online Learning

Tomas Ortega, Hamid Jafarkhani

We propose the first parameter-free decentralized online learning algorithms with network regret guarantees, which achieve sublinear regret without requiring hyperparameter tuning.…

cs.LG2025

Communication Compression for Distributed Learning without Control Variates

Tomas Ortega, Chun-Yin Huang, Xiaoxiao Li +1

Distributed learning algorithms, such as the ones employed in Federated Learning (FL), require communication compression to reduce the cost of client uploads. The compression metho…

eess.SP2024

LOS/NLOS Estimators for mmWave Cellular Systems With Blockages

Tomàs Ortega, Antonio Pascual-Iserte, Olga Muñoz

Designers of millimeter wave (mmWave) cellular systems need to evaluate line-of-sight (LOS) maps to provide good service to users in urban scenarios. In this letter, we derive esti…

cs.LG2024

Decentralized Optimization in Time-Varying Networks with Arbitrary Delays

Tomas Ortega, Hamid Jafarkhani

We consider a decentralized optimization problem for networks affected by communication delays. Examples of such networks include collaborative machine learning, sensor networks, a…