4arXiv cs.CL (Computation and Language)·
Reinforcement learning with verifiable rewards improves small-model legal machine translation
Researchers evaluate multiple training paradigms for legal machine translation, comparing supervised fine-tuning and reinforcement learning with verifiable rewards (RLVR) on small models (Qwen3.5 4B/9B, Gemma 3 12B) against frontier reasoning models. Using the Swiss multilingual legal system as a testbed, they find RLVR outperforms SFT for legal NMT and brings small models close to frontier performance, though a gap remains. The study also observes diminishing returns from re-training as model size increases. Code and models are publicly released.
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