Entropy-Gated Branching for Efficient Test-Time Reasoning

Xianzhi Li, Ethan Callanan, Abdellah Ghassel, Xiaodan Zhu


Abstract
Test-time compute methods can significantly improve the reasoning capabilities and problem-solving accuracy of large language models. However, these approaches require substantially more computational resources, with most computation wasted on exploring low-diversity branches where the model already exhibits high confidence. We observe that a small subset of uncertain reasoning steps has a disproportionately large impact on final prediction accuracy, and branching at these points tends to yield higher-quality and more diverse candidate reasoning steps. Therefore, we introduce Entropy-Gated Branching: a novel inference technique that dynamically allocates computational resources by selectively expanding prediction sequences only at points of high uncertainty. Our method leverages entropy as a gating mechanism to identify when branching is most beneficial, coupled with an external feedback model to rank and prune candidate branches. Empirical results on mathematical and financial reasoning benchmarks show that this strategy improves accuracy by 22.6% over standard inference while operating 31%-75% faster across math benchmarks than test-time beam search with higher performance. Our results show that dynamic resource allocation during inference can substantially improve both efficiency and effectiveness, offering a more scalable pathway to enhanced LLM reasoning capabilities. We release our code and tools here[<https://github.com/JXL884/entropy_gated_branching>]
Anthology ID:
2026.eacl-long.235
Volume:
Proceedings of the 19th Conference of the European Chapter of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
March
Year:
2026
Address:
Rabat, Morocco
Editors:
Vera Demberg, Kentaro Inui, Lluís Marquez
Venue:
EACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
5054–5069
Language:
URL:
https://preview.aclanthology.org/ingest-eacl/2026.eacl-long.235/
DOI:
Bibkey:
Cite (ACL):
Xianzhi Li, Ethan Callanan, Abdellah Ghassel, and Xiaodan Zhu. 2026. Entropy-Gated Branching for Efficient Test-Time Reasoning. In Proceedings of the 19th Conference of the European Chapter of the Association for Computational Linguistics (Volume 1: Long Papers), pages 5054–5069, Rabat, Morocco. Association for Computational Linguistics.
Cite (Informal):
Entropy-Gated Branching for Efficient Test-Time Reasoning (Li et al., EACL 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-eacl/2026.eacl-long.235.pdf