Yixuan Even Xu

profile.jpg

GHC 7203, Pittsburgh, PA 15213

yixuanx [at] andrew.cmu.edu

I am Yixuan (Even) Xu (徐翊轩), a second-year Ph.D. student in Computer Science at CSD, Carnegie Mellon University, where I am fortunate to be co-advised by Professor Zico Kolter and Professor Fei Fang. Prior to that, I completed my Bachelor of Engineering in Computer Science and Technology at Yao Class, Tsinghua University.

My research focuses on designing efficient and robust algorithms that improve real systems—across machine-learning pipelines and market-like mechanisms such as peer review. See my CV, publications and google scholar for more details about the projects I have done.

Besides research, I used to actively participate in competitive programming. See my CV for selected awards in OI, ICPC and CCPC. You can also find me in Codeforces, Atcoder and Project Euler.

News

Sep 18, 2025 One paper got accepted at NeurIPS 2025!
May 31, 2025 Our paper assignment algorithm was deployed in NeurIPS 2025!
May 26, 2025 Our team won 2nd place in ICPC North America Championship 2025!
Dec 12, 2024 Our paper-reviewer assignment algorithm was covered by NeurIPS conference blog!
Dec 9, 2024 Two papers got accepted at AAAI 2025 with one as an oral!
Nov 10, 2024 Our team won 1st place in ICPC East Central NA Regional 2024!
Oct 1, 2024 I am now officially advised by Prof. Zico Kolter and Prof. Fei Fang.
Sep 25, 2024 One paper got accepted at NeurIPS 2024!
Aug 26, 2024 I have just started my Ph.D. at CSD, Carnegie Mellon University.
Jun 29, 2024 I have just graduated as an outstanding graduate!
Jun 11, 2024 Our paper assignment algorithm was deployed in NeurIPS 2024!
Apr 18, 2024 Our team got 10th place in the 46th ICPC World Finals!
Apr 8, 2024 I have just decided to attend CMU CSD’s PhD program this fall.
Jan 23, 2024 One paper got accepted at WWW 2024 as an oral!
Dec 9, 2023 Two papers got accepted at AAAI 2024!
Nov 7, 2023 I was awarded Wang Dazhong Scholarship by Tsinghua University!
Sep 22, 2023 One paper got accepted at NeurIPS 2023 as a spotlight!
Sep 17, 2023 I was awarded Yao Award by IIIS!
Sep 1, 2023 I have finished my visit at Carnegie Mellon University.
Jun 23, 2023 One paper got accepted at ESA 2023!
Feb 10, 2023 I am visiting Carnegie Mellon, advised by Prof. Fei Fang and Prof. Vincent Conitzer.
Oct 28, 2022 I was awarded Jiang Nanxiang Scholarship by Tsinghua University!
Oct 25, 2021 I was awarded National Scholarship by Ministry of Education!

Selected Publications (Full List)

  1. Not All Rollouts are Useful: Down-Sampling Rollouts in LLM Reinforcement Learning
    Yixuan Even Xu*Yash Savani*Fei Fang, and J. Zico Kolter
    arXiv preprint arXiv:2504.13818, 2025
    Talk invited at Bosch Research Pittsburgh
  2. Antidistillation Sampling
    Yash Savani*, Asher Trockman*, Zhili FengYixuan Even XuAvi SchwarzschildAlexander Robey, Marc Finzi, and J. Zico Kolter
    In Advances in Neural Information Processing Systems, 2025
    Talk invited at OpenAI, Google and Simons Institute
  3. A One-Size-Fits-All Approach to Improving Randomness in Paper Assignment
    Yixuan Even XuSteven Jecmen, Zimeng Song, and Fei Fang
    In Advances in Neural Information Processing Systems, 2023
    Selected for Spotlight Presentation
    Deployed in NeurIPS 2024 and 2025
    Covered by NeurIPS conference blog
    Subsequent work deployed in AAAI 2026 and AAMAS 2026