aiqbench analysis
This arXiv preprint proposes Self-Policy Distillation (SPD), a method that improves LLMs by fine-tuning on their own outputs after projecting activations into a low-rank subspace derived from gradients on correctness-defining tokens. The authors report gains of up to 13% over prior self-distillation methods and up to 16.3% over pre-trained baselines across code, math, and multiple-choice QA, along with a 15.7% out-of-domain advantage. These are self-reported results on benchmarks, so readers should look for independent replication, but the approach of reducing reliance on external verification signals is worth watching for practitioners training models without costly labeled data.
Self-Policy Distillation via Capability-Selective Subspace Projection
arXiv:2605.22675v2 Announce Type: replace Abstract: Self-distillation bootstraps large language models (LLMs) by training on their own generations. However, existing methods either rely on external signals to curate self-generated outputs (e.g., correctness filtering, execution feedback, and reward search), which are costly and unavailable for the best-performing frontier models, or skip curation entirely and train on all raw outputs, an approach that is often domain-specific and hard to generalize. Both also share a deeper weakness that self-generated outputs entangle task-relevant capability with others, such as stylistic patterns, formatting artifacts, and model-specific errors, diluting the signal for the specific capability one aims to improve. In this paper, we propose Self-Policy Distillation (SPD), which achieves generalizable, capability selective with only minimal external signal (<5% labeled data in each domain). Specifically, SPD extracts a low-rank capability subspace from the model's own gradients on correctness-defining tokens, projects key-value (KV) activations into this subspace during self-generation, and fine-tunes on the resulting raw outputs with standard next-token prediction loss.Through extensive experiments across code generation, mathematical reasoning, and multiple-choice QA, we show that SPD achieves up to 13% improvement over state-of-the-art self-distillation methods and up to 16.3% improvement over pre-trained baselines. Notably,SPD demonstrates superior generalizability, achieving 15.7% better performance under out-of-domain generalization settings.
Abstract:Self-distillation bootstraps large language models (LLMs) by training on their own generations. However, existing methods either rely on external signals to curate self-generated outputs (e.g., correctness filtering, execution feedback, and reward search), which are costly and unavailable for the best-performing frontier models, or skip curation entirely and train on all raw outputs, an approach that is often domain-specific and hard to generalize. Both also share a deeper weakness that self-generated outputs entangle task-relevant capability with others, such as stylistic patterns, formatting artifacts, and model-specific errors, diluting the signal for the specific capability one aims to improve. In this paper, we propose Self-Policy Distillation (SPD), which achieves generalizable, capability selective with only minimal external signal (<5% labeled data in each domain). Specifically, SPD extracts a low-rank capability subspace from the model's own gradients on correctness-defining tokens, projects key-value (KV) activations into this subspace during self-generation, and fine-tunes on the resulting raw outputs with standard next-token prediction this http URL extensive experiments across code generation, mathematical reasoning, and multiple-choice QA, we show that SPD achieves up to 13% improvement over state-of-the-art self-distillation methods and up to 16.3% improvement over pre-trained baselines. Notably,SPD demonstrates superior generalizability, achieving 15.7% better performance under out-of-domain generalization settings.
Computation and Language (cs.CL)
arXiv:2605.22675 [cs.CL]
(or arXiv:2605.22675v2 [cs.CL] for this version)
https://doi.org/10.48550/arXiv.2605.22675 Focus to learn more arXiv-issued DOI via DataCite
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