NLP-FSDM at SemEval-2026 Task 4: Narrative Similarity via Multiple Negatives Ranking and Instruction-Based Embeddings

Abdessamad Benlahbib, Zouhir Essalmani, Achraf Boumhidi, Anass Fahfouh, Hamza Alami


Abstract
The identification of narrative similarity is a complex NLP challenge that requires modeling deeper plot and thematic alignment rather than relying solely on lexical overlap. In this paper, we detail the participation of team NLP-FSDM in SemEval-2026 Task 4. Our approach utilizes the bge-large-en-v1.5 encoder. For Track A, we fine-tune it using Multiple Negatives Ranking Loss (MNRL), while for Track B we rely on the pretrained encoder to generate fixed narrative representations. We achieved an accuracy of 65.50% in Track A and 62.50% in Track B. This paper provides an extensive comparison of our results with competitive baselines and top-performing systems, analyzing the efficacy of dense encoders in low-resource narrative contexts.
Anthology ID:
2026.semeval-1.88
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:
612–616
Language:
URL:
https://preview.aclanthology.org/ingest-acl-workshops/2026.semeval-1.88/
DOI:
Bibkey:
Cite (ACL):
Abdessamad Benlahbib, Zouhir Essalmani, Achraf Boumhidi, Anass Fahfouh, and Hamza Alami. 2026. NLP-FSDM at SemEval-2026 Task 4: Narrative Similarity via Multiple Negatives Ranking and Instruction-Based Embeddings. In Proceedings of the 20th International Workshop on Semantic Evaluation (2026), pages 612–616, San Diego, California, USA. Association for Computational Linguistics.
Cite (Informal):
NLP-FSDM at SemEval-2026 Task 4: Narrative Similarity via Multiple Negatives Ranking and Instruction-Based Embeddings (Benlahbib et al., SemEval 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-acl-workshops/2026.semeval-1.88.pdf