UniSD: Towards a Unified Self-Distillation Framework for Large Language Models

May 7, 2026ยท
Yiqiao Jin
Yiyang "Diana" Wang
Yiyang "Diana" Wang
,
Lucheng Fu
,
Yijia Xiao
,
Yinyi Luo
,
Haoxin Liu
,
B. Aditya Prakash
,
Josiah Hester
,
Jindong Wang
,
Srijan Kumar
ยท 1 min read
Diagram of the unified UniSD self-distillation framework and its component mechanisms. Overview of the UniSD framework (adapted from Figure 1 of the paper).
Abstract
Self-distillation (SD) offers a promising path for adapting large language models (LLMs) without relying on stronger external teachers. However, SD in autoregressive LLMs remains challenging because self-generated trajectories are free-form, correctness is task-dependent, and plausible rationales can still provide unstable or unreliable supervision. Existing methods mainly examine isolated design choices, leaving their effectiveness, roles, and interactions unclear. In this paper, we propose UniSD, a unified framework to systematically study self-distillation. UniSD integrates complementary mechanisms that address supervision reliability, representation alignment, and training stability, including multi-teacher agreement, EMA teacher stabilization, token-level contrastive learning, feature matching, and divergence clipping. Across six benchmarks and six models from three model families, UniSD reveals when self-distillation improves over static imitation, which components drive the gains, and how these components interact across tasks. Guided by these insights, we construct UniSD_full, an integrated pipeline that achieves the strongest overall performance, improving over the base model by +5.4 points and the strongest baseline by +2.8 points.
Type
Publication
arXiv preprint

Abstract

Self-distillation offers a promising path for adapting large language models without stronger external teachers, but it remains hard to apply reliably in autoregressive LLMs. We propose UniSD, a unified framework that systematically studies self-distillation by integrating complementary mechanisms โ€” multi-teacher agreement, EMA teacher stabilization, token-level contrastive learning, feature matching, and divergence clipping. Across six benchmarks and six models from three families, UniSD clarifies when and why self-distillation helps, and its integrated pipeline improves over the base model by +5.4 points and the strongest baseline by +2.8 points.