Yuki Ichihara

Starting in Aug 2026, I will join MBZUAI as a Ph.D. student, supervised by Junpei Komiyama.

My interests include Best-of-N and Minimum Bayes Risk decoding, language model alignment, and RL-based fine-tuning methods.

Profile photo

News

I will join MBZUAI as a Ph.D. student, supervised by Junpei Komiyama.

MO-GRPO was accepted to TACL.

Publications

  1. Reliable Chain-of-Thought via Prefix Consistency N. Iwase, Y. Ichihara, M. A. Quamar, J. Komiyama. arXiv preprint, 2026. Paper Code
  2. CITE: Anytime-Valid Statistical Inference in LLM Self-Consistency H. Ota, N. Iwase, Y. Ichihara, J. Komiyama, M. Imaizumi. arXiv preprint, 2026. Paper
  3. Consensus Group Relative Policy Optimization for Text Generation Y. Ichihara, Y. Jinnai, K. Ariu, E. Uchibe. Workshop at ACL, 2026. Paper Code
  4. MO-GRPO: Mitigating Reward Hacking of Group Relative Policy Optimization on Multi-Objective Problems Y. Ichihara, Y. Jinnai, T. Morimura, M. Sakamoto, R. Mitsuhashi, E. Uchibe. TACL, 2026. Paper Code
  5. Auto-Weighted Group Relative Preference Optimization for Multi-Objective Text Generation Tasks Y. Ichihara, Y. Jinnai. EMNLP Industry Track, 2025. Paper Code
  6. Theoretical Guarantees for Minimum Bayes Risk Decoding Y. Ichihara, Y. Jinnai, K. Ariu, T. Morimura, E. Uchibe. ACL, 2025. Paper
  7. Evaluation of Best-of-N Sampling Strategies for Language Model Alignment Y. Ichihara, Y. Jinnai, T. Morimura, K. Abe, K. Ariu, M. Sakamoto, E. Uchibe. TMLR, 2025. Paper
  8. A Policy Gradient Primal-Dual Algorithm for Constrained MDPs with Uniform PAC Guarantees T. Kitamura, T. Kozuno, M. Kato, Y. Ichihara, S. Nishimori, A. Sannai, S. Sonoda, W. Kumagai, Y. Matsuo. RLSW, 2024. Paper

Background

Education

MBZUAI, Ph.D. (incoming), supervised by Junpei Komiyama

Nara Institute of Science and Technology, Ph.D. program in Engineering (withdrew to re-enroll at MBZUAI)

Nara Institute of Science and Technology, M.S. in Engineering

Tokyo University of Science, B.S. in Electrical Engineering

Research Experience

JST SPRING Fellowship, Doctoral fellowship

CyberAgent AI Lab, Research Intern

ATR, Research Assistant

AIST, Research Assistant

Reviewing

Reviewer, ARR; ICML (nominated as Gold Reviewer)

Contact

For research discussions or collaboration, email is the best way to reach me.