Chronos: Learning Temporal Dynamics of Reasoning Chains for Test-Time Scaling
Kai Zhang, Jiayi Liao, Chengpeng Li, Ziyuan Xie, Sihang Li, Xiang Wang
Abstract
Test-Time Scaling (TTS) has emerged as an effective paradigm for improving the reasoning performance of large language models (LLMs). However, existing methods — most notably majority voting and heuristic token-level scoring — treat reasoning traces or tokens equally, thereby being susceptible to substantial variations in trajectory quality and localized logical failures. In this work, we introduce **Chronos**, a lightweight and plug-and-play chronological reasoning scorer that models each trajectory as a time series. Specifically, Chronos learns to capture trajectory features of token probabilities, assigns quality scores accordingly, and employs a weighted voting mechanism. Extensive evaluations on both in-domain and out-of-domain benchmarks demonstrate that Chronos consistently delivers substantial gains across a variety of models, with negligible computational overhead. Notably, Chronos@128 achieves relative improvements of 34.21% over Pass@1 and 22.70% over Maj@128 on HMMT25 using Qwen3-4B-Thinking-2507, highlighting its effectiveness.- Anthology ID:
- 2026.findings-acl.1376
- Volume:
- Findings of the Association for Computational Linguistics: ACL 2026
- Month:
- July
- Year:
- 2026
- Address:
- San Diego, California, United States
- Editors:
- Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
- Venue:
- Findings
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 27651–27664
- Language:
- URL:
- https://preview.aclanthology.org/ingest-acl/2026.findings-acl.1376/
- DOI:
- Cite (ACL):
- Kai Zhang, Jiayi Liao, Chengpeng Li, Ziyuan Xie, Sihang Li, and Xiang Wang. 2026. Chronos: Learning Temporal Dynamics of Reasoning Chains for Test-Time Scaling. In Findings of the Association for Computational Linguistics: ACL 2026, pages 27651–27664, San Diego, California, United States. Association for Computational Linguistics.
- Cite (Informal):
- Chronos: Learning Temporal Dynamics of Reasoning Chains for Test-Time Scaling (Zhang et al., Findings 2026)
- PDF:
- https://preview.aclanthology.org/ingest-acl/2026.findings-acl.1376.pdf