English

Pantheon: Personalized Multi-objective Ensemble Sort via Iterative Pareto Policy Optimization

Social and Information Networks 2025-05-21 v1

Abstract

In this paper, we provide our milestone ensemble sort work and the first-hand practical experience, Pantheon, which transforms ensemble sorting from a "human-curated art" to a "machine-optimized science". Compared with formulation-based ensemble sort, our Pantheon has the following advantages: (1) Personalized Joint Training: our Pantheon is jointly trained with the real-time ranking model, which could capture ever-changing user personalized interests accurately. (2) Representation inheritance: instead of the highly compressed Pxtrs, our Pantheon utilizes the fine-grained hidden-states as model input, which could benefit from the Ranking model to enhance our model complexity. Meanwhile, to reach a balanced multi-objective ensemble sort, we further devise an \textbf{iterative Pareto policy optimization} (IPPO) strategy to consider the multiple objectives at the same time. To our knowledge, this paper is the first work to replace the entire formulation-based ensemble sort in industry RecSys, which was fully deployed at Kuaishou live-streaming services, serving 400 Million users daily.

Keywords

Cite

@article{arxiv.2505.13894,
  title  = {Pantheon: Personalized Multi-objective Ensemble Sort via Iterative Pareto Policy Optimization},
  author = {Jiangxia Cao and Pengbo Xu and Yin Cheng and Kaiwei Guo and Jian Tang and Shijun Wang and Dewei Leng and Shuang Yang and Zhaojie Liu and Yanan Niu and Guorui Zhou and Kun Gai},
  journal= {arXiv preprint arXiv:2505.13894},
  year   = {2025}
}

Comments

Work in progrees

R2 v1 2026-07-01T02:23:54.454Z