ReTraceQA: Evaluating Reasoning Traces of Small Language Models in Commonsense Question Answering

Francesco Maria Molfese, Luca Moroni, Ciro Porcaro, Simone Conia, Roberto Navigli


Abstract
While Small Language Models (SLMs) have demonstrated promising performance on an increasingly wide array of commonsense reasoning benchmarks, current evaluation practices rely almost exclusively on the accuracy of their final answers, neglecting the validity of the reasoning processes that lead to those answers. To address this issue, we present ReTraceQA, a novel benchmark that introduces process-level evaluation for commonsense reasoning tasks. Our expert-annotated dataset reveals that in a substantial portion of instances (14-24%), SLMs provide correct final answers despite flawed reasoning processes, suggesting that the capabilities of SLMs are often overestimated by evaluation metrics that focus only on comparing the final answer with the ground truth. Indeed, we show that, when employing strong Large Language Models (LLMs) as automated judges for reasoning-aware evaluation rather than answer-only metrics, SLM performance drops significantly across all models and datasets, with scores decreasing by up to 25%.
Anthology ID:
2026.acl-long.1798
Volume:
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
38817–38832
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.1798/
DOI:
Bibkey:
Cite (ACL):
Francesco Maria Molfese, Luca Moroni, Ciro Porcaro, Simone Conia, and Roberto Navigli. 2026. ReTraceQA: Evaluating Reasoning Traces of Small Language Models in Commonsense Question Answering. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 38817–38832, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
ReTraceQA: Evaluating Reasoning Traces of Small Language Models in Commonsense Question Answering (Molfese et al., ACL 2026)
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PDF:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.1798.pdf
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