Chasing the Tail: Effective Rubric-based Reward Modeling for Large Language Model Post-Training - Zhang, Junkai; Wang, Zihao; Gui, Lin; Mysore Sathyendra, Swarnashree; Jeong, Jaehwan; Veitch, Victor; Wang, Wei; He, Yunzhong; Liu, Bing; Jin, Lifeng (International Conference on Learning Representations, 2026)