collaborators

8 papers

q-bio.PE2026

Immune history shapes recurrent epidemics of antigenically related variants

Ryuichi Kumata, Yuma Fujimoto, Hisashi Ohtsuki +1

Population immunity carried over from past epidemics of an antigenically variable pathogen influences the epidemic of new variants based on their antigenic similarity to the previo…

cs.LG2026

Linear Convergence in Games with Delayed Feedback via Extra Prediction

Yuma Fujimoto, Kenshi Abe, Kaito Ariu

Feedback delays are inevitable in real-world multi-agent learning. They are known to severely degrade performance, and the convergence rate under delayed feedback is still unclear,…

cs.GT2026

Time-Varyingness in Auction Breaks Revenue Equivalence

Yuma Fujimoto, Kaito Ariu, Kenshi Abe

Auction is applied for trade with various mechanisms. A simple but practical question is which mechanism, typically first-price or second-price auctions, is preferred from the pers…

cs.GT2025

Hamiltonian of polymatrix zero-sum games

Toshihiro Ota, Yuma Fujimoto

The understanding of a dynamical system's properties can be significantly advanced by establishing it as a Hamiltonian system and then systematically exploring its inherent symmetr…

cs.LG2025

Learning from Delayed Feedback in Games via Extra Prediction

Yuma Fujimoto, Kenshi Abe, Kaito Ariu

This study raises and addresses the problem of time-delayed feedback in learning in games. Because learning in games assumes that multiple agents independently learn their strategi…

cs.GT2025

Synchronization in Learning in Periodic Zero-Sum Games Triggers Divergence from Nash Equilibrium

Yuma Fujimoto, Kaito Ariu, Kenshi Abe

Learning in zero-sum games studies a situation where multiple agents competitively learn their strategy. In such multi-agent learning, we often see that the strategies cycle around…