Rubric Curriculum RL Improves RLVR in Non-Verifiable Domains
The paper introduces Rubric Curriculum RL (RcRL), a method that exploits the generation-verification gap in domains without ground-truth rewards by combining pairwise preferences over rollouts with a curriculum over rubric criteria. This creates a more discriminative and non-stationary training signal, avoiding the plateau seen in baselines. RcRL achieves a 70.5% human win rate on creative writing and improves HealthBench performance by 14.6% (full set) and 25.4% (consensus subset), outperforming all training baselines.
Why it matters: This presents a concrete, novel training method with measurable gains in open-ended domains, addressing a key limitation of RLVR.