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CommunityJev Models & Reimplementations
Towards Foundation Decision Models: Drex
arXiv paper introducing Drex, a family of four open decision models at 8B, 9B, 35B with 3B active, and 27B parameters. Reports 67.52 on Decision Index 0.4.1 versus 60.70 for Jev 1.14.0.
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- Added
- Nov 2026
Highlights
- Four open decision models: 8B (DLM), 9B (v1.5), 35B with 3B active (v2.0), and 27B (Max).
- Requests pair a state (document, record, or agent context, optionally with images) with questions offering options, yes/no, or ordered scales.
- Training combines supervised fine-tuning with reinforcement learning from adjusted feedback (RLAF), plus vision tuning for Max.
- Max scores 67.52 on the Decision Index 0.4.1 public suite versus 60.70 for Jev 1.14.0.
- Max answers a typical request in 183 ms, against about 2.0 s for GPT-6 Sol and 3.5 s for Claude Opus 5.5.
Questions about this entry
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Four open decision models: DLM at 8B parameters, v1.5 at 9B, v2.0 at 35B with 3B active, and Max at 27B parameters.
Each request pairs a state, such as a document, record, or agent context optionally with images, with questions about it. Each question asks for a choice among options, a yes/no judgment, or a score on an ordered scale.
Training combines supervised fine-tuning with reinforcement learning from adjusted feedback (RLAF), plus vision tuning for Max. Ablations show RLAF improves accuracy and consistency losses improve robustness to option order.
On Decision Index 0.4.1, Max scores 67.52 on the public suite against 60.70 for Jev 1.14.0, which the paper describes as a new state of the art among the decision models compared.
Max answers a typical request in 183 ms, against about 2.0 s for GPT-6 Sol and 3.5 s for Claude Opus 5.5.
Yes. All four models are open source, and the paper points to the nace-ai/drex-decision-models repository.
Consistency losses during training improve robustness to option order, and the paper reports that Max's outputs are stable under option reordering.
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