@inproceedings{mohammed-bouchekif-2026-psl,
title = "{PSL} at {QIAS} 2026: Which Models Perform Better in {A}rabic Inheritance Reasoning?",
author = "Mohammed, amine and
Bouchekif, Chahinez",
editor = "Al-Khalifa, Hend and
El-Haj, Mo and
Ezzini, Saad",
booktitle = "The 7th Workshop on Open-Source {A}rabic Corpora and Processing Tools ({OSACT}7) with 5 Shared Tasks",
month = may,
year = "2026",
address = "Palma, Mallorca (Spain)",
publisher = "Association for Computational Linguistics",
url = "https://aclanthology.org/2026.osact-1.25/",
doi = "10.63317/3q67jok59yam",
pages = "204--208",
abstract = "This paper presents the participation of team PSL in the QIAS 2026 Shared Task on Arabic Islamic inheritance reasoning. The task evaluates the ability of large language models to solve inheritance cases that require legal interpretation, multi-step reasoning, and precise numerical computation. We compare commercial and open-source models under a unified prompting strategy to assess their effectiveness in structured legal reasoning with minimal task-specific adaptation. Our results show a clear gap in reliability between the two model families. Commercial models demonstrate stronger performance in identifying eligible heirs, applying exclusion rules, and maintaining consistency across reasoning steps. In contrast, open-source models exhibit greater instability, particularly in cases involving dependent legal decisions and fractional share adjustments. The best performance is achieved by Gemini 2.5 Flash, with an MRE of 0.989."
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%0 Conference Proceedings
%T PSL at QIAS 2026: Which Models Perform Better in Arabic Inheritance Reasoning?
%A Mohammed, amine
%A Bouchekif, Chahinez
%Y Al-Khalifa, Hend
%Y El-Haj, Mo
%Y Ezzini, Saad
%S The 7th Workshop on Open-Source Arabic Corpora and Processing Tools (OSACT7) with 5 Shared Tasks
%D 2026
%8 May
%I Association for Computational Linguistics
%C Palma, Mallorca (Spain)
%F mohammed-bouchekif-2026-psl
%X This paper presents the participation of team PSL in the QIAS 2026 Shared Task on Arabic Islamic inheritance reasoning. The task evaluates the ability of large language models to solve inheritance cases that require legal interpretation, multi-step reasoning, and precise numerical computation. We compare commercial and open-source models under a unified prompting strategy to assess their effectiveness in structured legal reasoning with minimal task-specific adaptation. Our results show a clear gap in reliability between the two model families. Commercial models demonstrate stronger performance in identifying eligible heirs, applying exclusion rules, and maintaining consistency across reasoning steps. In contrast, open-source models exhibit greater instability, particularly in cases involving dependent legal decisions and fractional share adjustments. The best performance is achieved by Gemini 2.5 Flash, with an MRE of 0.989.
%R 10.63317/3q67jok59yam
%U https://aclanthology.org/2026.osact-1.25/
%U https://doi.org/10.63317/3q67jok59yam
%P 204-208
Markdown (Informal)
[PSL at QIAS 2026: Which Models Perform Better in Arabic Inheritance Reasoning?](https://aclanthology.org/2026.osact-1.25/) (Mohammed & Bouchekif, OSACT 2026)
ACL