aiqbench analysis
This research exposes a significant upstream bias in large language models against the less prestigious Sa'idi Egyptian Arabic dialect, demonstrating that these models exhibit lower performance and altered preference ratings when processing this specific sub-dialect compared to the dominant Cairene variant. The study underscores critical gaps in current NLP resource development and highlights how socioeconomic hierarchies embedded in training data directly degrade model utility for diverse linguistic communities.
Some Dialects Are More Equal Than Others: Non-Prestigious Arabic Dialectal Bias in LLMs
arXiv:2609.23955v1 Announce Type: new Abstract: Previous work on Egyptian Arabic in NLP has focused largely on the prestigious Cairene Egyptian Arabic (CEA) dialect, resulting in a lack of representation for the less prestigious Sa'idi Egyptian Arabic (SEA) dialect both in LLM and resource development. Does this lack of representation influence an LLM's view of the acceptability of SEA (upstream), and does an upstream bias against SEA lead to worse performance (downstream)? We investigate the upstream effect of SEA dialectal features on LLM preferences in a Targeted Syntactic Evaluation (TSE) task which reveals a significant bias against SEA across multiple LLMs. We then analyze the effect of these same features on downstream model performance on MMLU benchmarks and show that models experience a degradation in performance when presented with SEA. This work highlights the need for further exploration on how sub-dialectal variation impacts language technologies.
Abstract:Previous work on Egyptian Arabic in NLP has focused largely on the prestigious Cairene Egyptian Arabic (CEA) dialect, resulting in a lack of representation for the less prestigious Sa'idi Egyptian Arabic (SEA) dialect both in LLM and resource development. Does this lack of representation influence an LLM's view of the acceptability of SEA (upstream), and does an upstream bias against SEA lead to worse performance (downstream)? We investigate the upstream effect of SEA dialectal features on LLM preferences in a Targeted Syntactic Evaluation (TSE) task which reveals a significant bias against SEA across multiple LLMs. We then analyze the effect of these same features on downstream model performance on MMLU benchmarks and show that models experience a degradation in performance when presented with SEA. This work highlights the need for further exploration on how sub-dialectal variation impacts language technologies.
Computation and Language (cs.CL)
arXiv:2609.23955 [cs.CL]
(or arXiv:2609.23955v1 [cs.CL] for this version)
https://doi.org/10.48550/arXiv.2609.23955 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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