alkhder at ImageEval 2026 Shared Tasks: Constrained Selection and Rotation-Averaged Logit Scoring for Multimodal Hallucination Detection

Maher Pasa, Maria Hanini, Amro Najjar, Hasan Alkhder


Abstract
We describe our submission to Subtask 1b of ImageEval 2026. The task consists of selecting the single visually valid statement from three candidates paired with an image, and is in both English and Modern Standard Arabic (MSA). Our system uses a pre-trained 7B vision–language model in a zero-shot setting, without task-specific training or fine-tuning. We formulate the task as a constrained selection problem and choose the answer using next-token log-probabilities. To reduce answer-position bias, we apply a Latin-square rotation to the candidate statements. Our system achieves CI scores of 0.0510 on the English test set and 0.0960 on the MSA test set, reducing CI relative to the official 3B baselines reported on devtest by 83.7% and 80.4%, respectively.
Anthology ID:
2026.arabicnlp-sharedtasks.92
Volume:
Proceedings of The Fourth Arabic Natural Language Processing Conference: Shared Tasks
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Muhammad Abdul-Mageed, Tamer Elsayed, Houda Bouamor, Samhaa El-Beltagy, Hend Al-Khalifa, Ahmed Abdelali, AbdelRahim Elmadany, Abdellah El Mekki, Kareem Darwish, Sakhar Alkhereyf, Hamzah Luqman, Salam Khalifa, Samar Magdy, Zaid Alyafeai, Injy Hamed, Wajdi Zaghouani, Imed Zitouni
Venue:
ArabicNLP
SIG:
SIGARAB
Publisher:
Association for Computational Linguistics
Note:
Pages:
740–746
Language:
URL:
https://aclanthology.org/2026.arabicnlp-sharedtasks.92/
DOI:
Bibkey:
Cite (ACL):
Maher Pasa, Maria Hanini, Amro Najjar, and Hasan Alkhder. 2026. alkhder at ImageEval 2026 Shared Tasks: Constrained Selection and Rotation-Averaged Logit Scoring for Multimodal Hallucination Detection. In Proceedings of The Fourth Arabic Natural Language Processing Conference: Shared Tasks, pages 740–746, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
alkhder at ImageEval 2026 Shared Tasks: Constrained Selection and Rotation-Averaged Logit Scoring for Multimodal Hallucination Detection (Pasa et al., ArabicNLP 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.arabicnlp-sharedtasks.92.pdf