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UltraBERT Jev 380M (sigmoid-norm)
Fine-tuned UltraBERT-380M decision model on Hugging Face that scores a state, question, and option list in one forward pass. Uses sigmoid of yes minus no normalized over options; 72.8% dev and 71.9% test accuracy across 13 datasets, with an evidence head documented on the card.
- Reading time
- 2 min
- Published by
- Community
- Added
- Nov 2026
Highlights
- Reads a state, a question, and a list of options and picks one option in a single forward pass, without generating text.
- Option k is scored from masked-token logits as sigmoid of " yes" minus " no", divided by the sum over options.
- Trained for one epoch at batch 32 and learning rate 1.5e-5 on the 13-dataset Reason+Long mixture with Nimble added.
- Reports 72.8% mean accuracy on the dev split and 71.9% on the test split across 13 datasets.
- Model card includes an Evidence head section alongside usage, related checkpoints, and limitations.
Questions about this entry
Short answers drawn from the linked project or page.
Load it with transformers AutoTokenizer and AutoModelForMaskedLM using the repo id, in fp32 via dtype=torch.float32, then move it to CUDA and call eval(). It was tested with transformers 5.20.2 and torch 2.9.
Both are UltraBERT-380M fine-tunes on the same 13-dataset mixture. This one scores options with sigmoid of " yes" minus " no" divided by the sum over options, and reports 72.8% dev and 71.9% test accuracy.
Yes. Masked-token logits are around 200 in magnitude, and bf16 weights changed accuracy by up to 8 points on long documents (MuSiQue). All reported numbers use fp32 weights.
No. The model was trained on a specific prompt format with the tokens " yes" and " no"; plain fill-mask use will not give the reported results, so the card's prompt must be used exactly.
Apache-2.0. It is a fine-tune of dmis-lab/UltraBERT-380M with 429,966,336 F32 parameters in one unsharded safetensors file.
arxiv:2610.02076, "LLM-as-Jev: LLMs Are Already Jev-Style Decision Models -- When and How to Fine-Tune Them", and arxiv:2502.09604, "SelfCite: Self-Supervised Alignment for Context Attribution in Large Language Models".
It is an English encoder that picks one option per forward pass and generates no text. It requires the exact trained prompt format and fp32 weights, and the card documents limitations.
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