collaborators

5 papers

cs.LG2026

Combinatorial Allocation Bandits with Nonlinear Arm Utility

Yuki Shibukawa, Koichi Tanaka, Yuta Saito +1

A matching platform is a system that matches participants of different types, such as companies and job-seekers. In such a platform, maximizing matches may concentrate assignments…

cs.LG2026

Beyond Match Maximization and Fairness: Retention-Optimized Two-Sided Matching

Ren Kishimoto, Rikiya Takehi, Koichi Tanaka +4

On two-sided matching platforms such as online dating and recruiting, recommendation algorithms often aim to maximize the total number of matches. However, this objective creates a…

cs.LG2026

Off-Policy Learning with Limited Supply

Koichi Tanaka, Ren Kishimoto, Bushun Kawagishi +4

We study off-policy learning (OPL) in contextual bandits, which plays a key role in a wide range of real-world applications such as recommendation systems and online advertising. T…

cs.LG2026

Off-Policy Evaluation for Ranking Policies under Deterministic Logging Policies

Koichi Tanaka, Kazuki Kawamura, Takanori Muroi +6

Off-Policy Evaluation (OPE) is an important practical problem in algorithmic ranking systems, where the goal is to estimate the expected performance of a new ranking policy using o…

stat.ML2024

Effective Off-Policy Evaluation and Learning in Contextual Combinatorial Bandits

Tatsuhiro Shimizu, Koichi Tanaka, Ren Kishimoto +3

We explore off-policy evaluation and learning (OPE/L) in contextual combinatorial bandits (CCB), where a policy selects a subset in the action space. For example, it might choose a…