arXiv Computation and Language By Peter Schneider-Kamp, Jacob Nielsen, Gianluca Barmina, Danial Namazifard, Annemette Brok Pirchert, Kenneth Enevoldsen, Lukas Galke Poech

Mimir: A Sub-2B Hierarchical Reasoning Model Trained on Permissible Data Punches Above Its Weight Class

Read the original on arXiv Computation and Language →

Mimir is a 1.78‑B parameter language model built on the Hierarchical Reasoning Model Text (HRM‑Text) architecture, which interleaves low‑level and high‑level transformer stacks. It is trained from scratch on a curated mix of 161 instruction, reasoning, tool‑use, multilingual, and synthetic datasets totaling 70.5 B tokens per epoch (103 B for the continued‑training version Mimir v1.5), using only data that meets permissibility criteria. Across 20 benchmarks in English, Danish, and Math & Code, Mimir v1.5 outperforms all other sub‑2 B models and matches or exceeds the performance of larger 9 B‑parameter models, while memorisation audits show low risk and inference‑time ablations reveal graceful degradation when adjusting low‑level stack applications.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv Computation and Language.

arXiv AI
Oct 2

Closing the Loop: Practical Training Recipes for Looped Language Models

The paper presents practical training recipes for looped language models, showing that a compute‑efficient pipeline can reduce the training budget from 7.7 T tokens to 310 B tokens while maintaining strong reasoning performance. In controlled experiments, a 1.4 B LoopLM outperforms a parameter‑matched dense model on 12 benchmarks, achieving significant gains on GSM8K, MATH, and DROP, and approaches a 3.9 B dense model at matched inference compute. The authors also provide a minimal recipe to convert pretrained dense models into looped ones, demonstrating improvements on Qwen3‑1.7B‑Base across multiple data regimes.

By Andrei Marchenko, Viacheslav Bezrukov, Oleg Kashurin, Inessa Fedorova, Dmitry Bocharov, Yuliana Shakhvalieva, Maria Tikhonova, Valerii Ternovskii
arXiv Machine Learning
Sep 30

It's All Training: A Fully Synthetic Single-Stage Recipe for LLMs

arXiv:2609.37891v1 Announce Type: cross Abstract: Current pre-training datasets are derived from web crawls, with all their issues, and were not designed to support mid- and post-training pipelines--...

By Pierre-Carl Langlais, Pieter Delobelle, Yannick Detrois, Pavel Chizhov, Carlos Rosas-Hinostroza, Neil Si Smail, Benjamin Burtin, Hanna Shcharbakova, Ivan Yamshchikov, Anastasia Stasenko
arXiv Computation and Language
Aug 27

Rethinking the Multilingual Reasoning Gap with Layer Swap

The study investigates the performance gap between native-language reasoning and English-pivoted reasoning in large language models. By creating extensive multilingual reasoning datasets and fine‑tuning specialists on Qwen/Qwen3-8B-Base, the authors find that the native reasoning gap is much smaller (1.9–3.5%) than previously reported. They analyze weight‑space changes, discover a language‑agnostic reasoning core in the middle layers, and propose a Layer Swap technique that transfers these mid‑layer updates from an English specialist to native specialists, effectively closing most of the gap while maintaining native chain‑of‑thought output.

By Maxence Lasbordes, Am\'elie Chatelain, Djam\'e Seddah