# mammoth-1

Baseten's research lab released two open-source decision models, mammoth-1 (27B) and elephant-1 (9B), which return a probability distribution over every possible answer instead of generating text. mammoth-1 ranks first among 208 decision models on the Jev Decision Index 0.4, while elephant-1 is tied for eighth there and is the leading 9B decision model, and is tied for first with d1-ultra on the separate Artificial Analysis Decision Index. Both were post-trained from Qwen3.5-9B and Qwen3.5-27B on 6.21 million decision-making examples, are free to try for a week on Baseten Model APIs, and are open-source on Hugging Face.

Baseten's research lab released two open-source decision models, mammoth-1 (27B) and elephant-1 (9B), which return a probability distribution over every possible answer instead of generating text. mammoth-1 ranks first among 208 decision models on the Jev Decision Index 0.4, while elephant-1 is tied for eighth there and is the leading 9B decision model, and is tied for first with d1-ultra on the separate Artificial Analysis Decision Index. Both were post-trained from Qwen3.5-9B and Qwen3.5-27B on 6.21 million decision-making examples, are free to try for a week on Baseten Model APIs, and are open-source on Hugging Face.