arXiv Computation and Language

Where Does Long-Context Supervision Actually Go? Effective-Context Exposure Balancing

The paper introduces EXACT, a supervision-allocation objective that reweights long-context targets by inverse frequency to address a token-level supervision mismatch in packed training. Across seven Qwen/LLaMA configurations, EXACT consistently improves NoLiMa and RULER metrics, with notable gains on Qwen2.5-0.5B and LLaMA-3.2-3B. Standard QA and reasoning performance remain largely unchanged, and a distance-resolved probe shows benefits primarily when evidence is thousands of tokens away.

arXiv AI
Jul 13

Self-Guided Test-Time Training for Long-Context LLMs

arXiv:2607. 09415v1 Announce Type: cross Abstract: Long-context processing has become increasingly important for large language models (LLMs), but simply extending the context window does not guarantee effective utilization of long inputs.

By Xinyu Zhu, Zhe Xu, Xiaohan Wei, Yunchen Pu, Fei Tian, Chonglin Sun, Kaushik Rangadurai, Hua Zhi, Frank Shyu, Sandeep Pandey, Luke Simon, Yu Meng, Xi Liu
arXiv Computation and Language
Oct 22

Don't Stop Long-Context Continual Pre-Training Too Early: An Empirical Scaling Law

The paper studies how long‑context continual pre‑training (LCCP) scales with token budget and model size. An empirical additive power law is derived that predicts LCCP performance across five model scales and over a hundred budget configurations, and a new Constant‑Last4 protocol is introduced for stable monitoring. Experiments show that performance continues to improve without clear saturation, even after 128K context extension and fine‑tuning, indicating that scaling LCCP yields transferable gains for downstream tasks.

By Ziqing Qiao, Xiaoyue Xu, Sikui Zhang, Yinuo Xu, Bingxiang He, Chaojun Xiao, Xu Han
arXiv Computation and Language
Oct 15

MemDuet: Learning Dual-Process Memory for Long-Context Reasoning

arXiv:2610.19928v1 Announce Type: new Abstract: Reasoning over infinitely long documents is becoming a reality with recurrent memory agents. However, increasing context length exacerbates the trade-o...

By Jiangcheng Song, Haodong Jing, Yulin Mu, Lesong Tao, Jixin Wang, Jin Cui, Tianjing Ren, Runxuan Xie, Yongqiang Ma, Nanning Zheng
arXiv AI
Jul 8

LongCrafter: Towards Diverse Long-Context Understanding via Evidence-Graph-Guided Instruction Synthesis

arXiv:2607. 06160v1 Announce Type: cross Abstract: Synthesizing long-context supervised fine-tuning (SFT) data is a scalable way to enhance the long-context understanding of large language models (LLMs), yet existing approaches share three limitations: narrow task coverage, insufficient instruction difficulty, and a lack of faithfulness supervision.

By Chenhao Yuan, Yinhao Xu, Shuwen Xu, Xizhi Yang, Jiaxiang Liu, Chenxi Zhou, Shaoping Huang, Haolin Ren, Pengfei Cao, Jun Zhao, Kang Liu
arXiv Machine Learning
Sep 23

The Sirens' Song: When Proximal Background Context Overshadows Distant Evidence

The paper introduces the Proximity Trap, a problem where long-context language models fail to attend to distant evidence because of competition from abundant, irrelevant proximal background. To mitigate this, the authors propose LYRA, a t‑distributed directional matching mechanism that reshapes the retrieval distribution to focus more on task‑relevant evidence while preserving positional information. Experiments on LongBench‑v2, RULER, and LongBench show consistent performance gains, and a new benchmark, ProxBench, is presented to evaluate distant evidence usage under varying proximal interference.

By Xiaoyu Yang, Jie Lu, Wei Duan, En Yu