AKCIT-UFG at SemEval-2026 Task 8: Structured Chunking and Optimized Query Reformulation for Efficient Multi-Turn Retrieval

David Ferreira, Wilson Ramos, Priscila Ribeiro, Emanuel Passinato, Diogo Fernandes, Arlindo Filho


Abstract
This submission investigates efficient multi-turn retrieval under constrained computational settings. We analyze how passage granularity and conversational query rewriting affect retrieval effectiveness across four benchmark domains. Using compact, locally deployable components, we show that smaller passage segmentation improves early-rank performance and that lightweight keyword-oriented query reformulation substantially enhances dense retrieval quality.Importantly, we observe that rewriting interacts differently with encoder backbones: some compact models benefit significantly from increased query specificity, while others degrade, indicating sensitivity to rewrite-induced distribution shifts. Our findings demonstrate that competitive multi-turn retrieval does not require large proprietary models, but can emerge from principled structural and preprocessing design choices. The results highlight the importance of aligning chunking strategy, rewriting policy, and encoder characteristics in resource-efficient MT-RAG systems.
Anthology ID:
2026.semeval-1.395
Volume:
Proceedings of the 20th International Workshop on Semantic Evaluation (2026)
Month:
July
Year:
2026
Address:
San Diego, California, USA
Editors:
Ekaterina Kochmar, Debanjan Ghosh, Kai North, Mamoru Komachi
Venues:
SemEval | WS
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
3149–3155
Language:
URL:
https://preview.aclanthology.org/ingest-acl-workshops/2026.semeval-1.395/
DOI:
Bibkey:
Cite (ACL):
David Ferreira, Wilson Ramos, Priscila Ribeiro, Emanuel Passinato, Diogo Fernandes, and Arlindo Filho. 2026. AKCIT-UFG at SemEval-2026 Task 8: Structured Chunking and Optimized Query Reformulation for Efficient Multi-Turn Retrieval. In Proceedings of the 20th International Workshop on Semantic Evaluation (2026), pages 3149–3155, San Diego, California, USA. Association for Computational Linguistics.
Cite (Informal):
AKCIT-UFG at SemEval-2026 Task 8: Structured Chunking and Optimized Query Reformulation for Efficient Multi-Turn Retrieval (Ferreira et al., SemEval 2026)
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PDF:
https://preview.aclanthology.org/ingest-acl-workshops/2026.semeval-1.395.pdf
Supplementarymaterial:
 2026.semeval-1.395.SupplementaryMaterial.zip