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20232026
most citedVerbosity Bias in Preference Labeling by Large Language Models

11 citations · 11 across the 6 of their papers we have counts for

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5 papers · 1 filter

cs.LG2026

Safety Hacking in Constrained Best-of- Inference-time Scaling

Akifumi Wachi, Takumi Tanabe, Youhei Akimoto

Inference-time pipelines often sample multiple outputs, filter them with a learned safety model, and return the proxy-feasible output with the highest learned reward. We show that…

cs.LG2026

Evolutionary Bilevel Reward Shaping for Generalization in Reinforcement Learning

Ekasit Usaratniwart, Xilin Gao, Marc Ong +1

Reinforcement learning (RL) often suffers from performance degradation when deployed in environments that differ from those encountered during training. Existing techniques such as…

cs.LG2026

Sample-Efficient Hypergradient Estimation for Decentralized Bi-Level Reinforcement Learning

Mikoto Kudo, Takumi Tanabe, Akifumi Wachi +1

Many strategic decision-making problems, such as environment design for warehouse robots, can be naturally formulated as bi-level reinforcement learning (RL), where a leader agent…

cs.LG2025

Cost-Minimized Label-Flipping Poisoning Attack to LLM Alignment

Shigeki Kusaka, Keita Saito, Mikoto Kudo +3

Large language models (LLMs) are increasingly deployed in real-world systems, making it critical to understand their vulnerabilities. While data poisoning attacks during RLHF/DPO a…

cs.LG2025

A Provable Approach for End-to-End Safe Reinforcement Learning

Akifumi Wachi, Kohei Miyaguchi, Takumi Tanabe +2

A longstanding goal in safe reinforcement learning (RL) is a method to ensure the safety of a policy throughout the entire process, from learning to operation. However, existing sa…