Cord learned when to break from confidence decoding for masked diffusion language models, lifting average task success from 32.0 to 48.2 percent
AspireAI community · arXiv
Masked diffusion language models decode by revealing tokens in some order, and the usual rule - reveal whichever token the model is most confident about - ignores whether that reveal actually helps the rest of the generation. Cord keeps confidence decoding as a stable reference and learns a small prompt-conditioned residual over generation direction, proximity to revealed context and two-sided infilling, sampling one low-dimensional coefficient matrix per rollout so a single policy decision induces a whole reveal trajectory. Across three dLLMs and five reasoning, code and constraint-satisfaction benchmarks, average task success rose from 32.0% to 48.2%, beating the best per-domain fixed residual. It costs 0.53 million trainable parameters, no extra backbone forward passes and 5.39% inference latency overhead, and because it is trained as a contextual bandit on sequence-level rewards there is no step-level credit assignment.
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