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arXiv:2609.38721AICV30 sep 2026

UniEvo-VL: An On-policy Self-Distillation Training Recipe for Multimodal Model Self-improvement

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UNIEVO-VL (GPT5.6-LUNA)0.88UNIEVO-VL + VERIFICATION0.82UNIEVO-VL0.81BASE0.7501 GENEVAL NATIVE SCORE
fig. geneval native scoreSelf-critique helps; a stronger critic helps more

An image model critiques its own pictures, then trains itself to get them right the first time.

0.808GenEval score (0–1)

GenEval score after self-training

No external teacher or reward model needed for the gain

How it works

  1. Critiques help only once

    A unified model can spot flaws in its own images, but fixing them needs an extra reflection pass every time.

  2. Same model, two roles

    The teacher copy sees a critique-revised prompt; the student sees the original. The student matches the teacher's denoising steps.

  3. Better first drafts

    Direct generation improves on GenEval, GenEval2 and OCR. Reflection still adds gains on top.

generateinspectrewriteteacher contextLoRA updateOriginalpromptDraft imageSelfcritiqueVerifiedrevised promptTeacher-studentmatchingUpdatedgeneratorgenerateinspectrewriteteacher contextLoRA updateOriginalpromptDraft imageSelfcritiqueVerifiedrevised promptTeacher-studentmatchingUpdatedgenerator

What they found

Which comes out on top on GenEval native score?

Self-training over updates

try it

Drag the number of optimizer updates and watch the direct-generation score.

Optimizer updatesGenEval scorebase modelevolved model
GenEval score
medium
here
base model
Gains build from corrective experience then level off; easy prompts may slip slightly.Illustrative model, not the paper's data

Terms

6 terms

Privileged information The critique-revised prompt only the teacher sees during training.

A cook tastes a dish, writes notes, cooks it again following the notes, then practices until the first attempt matches the note-guided version.

Where it breaks
The model never trains on the corrected dish itself, only step-by-step predictions.

Limits

  • Text-rendering gains are mixed; unverified setup falls below base on OCR.
  • Easy prompts regress by 1–4 points on a 0–100 scale.
  • Biggest gains need a stronger external critic, not pure self-feedback.
From the paper