j-raghavan/s1-gemma4-26b-decision

VISIONPricing:Input $0.4 / Cached $0.08 / Output $0.8Concurrent Unit Cost:2Model Size:26BQuant:FP8Context Size:32kTool Calling:SupportedPublished:Oct 7, 2026License:apache-2.0Architecture:Transformer0.0K Open Weights Featherless Exclusive Cold

j-raghavan/s1-gemma4-26b-decision is an open, calibrated System One (s1) decision model based on google/gemma-4-26B-A4B-it, a 26 billion parameter mixture-of-experts architecture with approximately 4 billion active parameters. Fine-tuned with LoRA on 100,000 typed decision rows, this model provides probabilities for every option in a single forward pass given a state and a typed question, without generating text. It excels at structured decision-making tasks, offering calibrated probability outputs for choice, yes/no, and scoring questions.

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s1-gemma4-26b-decision: A Calibrated Decision Model

s1-gemma4-26b-decision is an open, calibrated System One (s1) decision model, fine-tuned from Google's gemma-4-26B-A4B-it (a 26B parameter Mixture-of-Experts model with ~4B active parameters). Unlike traditional LLMs that generate text, s1 provides a probability for every option in a single forward pass, making it highly efficient for structured decision tasks.

Key Capabilities

  • Direct Probability Outputs: Given a state (text or JSON) and a typed question, it returns probabilities for each option without generating conversational text.
  • Multiple Question Types: Supports choice (keyed options with descriptions), noul (yes/no conditions), and score (ordered levels with probabilities and expected level).
  • High Performance: Achieves strong results on held-out test sets, including 0.817 (calibrated) on JevBench subsets and 0.981 (calibrated) on custom structured decisions.
  • Efficiency: Offers low latency, with median decision times of 28 ms (FP8) or 40 ms (bf16) on an NVIDIA RTX PRO 6000.
  • Quantized Support: Available in int4 quantization for local deployment (e.g., via Ollama), enabling use on consumer hardware like Apple-silicon laptops with comparable accuracy.

Good For

  • Automated Decision-Making: Ideal for applications requiring rapid, probabilistic decisions based on structured inputs.
  • Routing and Classification: Can be used to route customer tickets, classify intents, or make binary choices with confidence scores.
  • Resource-Constrained Environments: The efficient single-pass inference and int4 quantization make it suitable for deployment where computational resources are limited.
  • Research and Development: The open-source nature of its code, data, and evaluation allows for transparent research and further development in calibrated decision models.