aiqbench analysis
This research investigates how Arabic large language models encode dialectal features, revealing that while sparse neurons exist for specific varieties, they are insufficient for inducing dialects from standard prompts without fine-tuning. The study demonstrates that successful steering relies on distributed activation directions rather than localized neuron populations, offering a novel inference-time mechanism to improve dialect generation.
Can Dialects Be Steered Like Languages? Sparse Neurons and Distributed Directions in Arabic LLMs
arXiv:2607.03936v2 Announce Type: replace Abstract: Dialectal data are scarce relative to Modern Standard Arabic (MSA), causing Arabic LLMs to overproduce MSA and struggle with dialectally accurate generation. This raises a fundamental interpretability question about where and how dialectal features are encoded within model internals and whether these representations can improve dialect generation without fine-tuning. We study two inference-time approaches as interpretability probes and control mechanisms. First, neuron-level analysis identifies sparse populations that encode dialect-specific features and tests whether amplifying or suppressing them steers model outputs toward target dialects. Second, vector steering extracts dialect-specific activation directions and injects them during inference, motivated by feature entanglement at the neuron level. We find that these neurons are real but only partially explanatory. They occupy under 1\% of MLP dimensions but span only 5\% to 21\% of the residual dialect direction. This limited coverage is causally consequential. Neuron steering reinforces dialect in some varieties when the prompt is already dialectal but cannot induce it from MSA prompts, whereas vector steering succeeds in both settings. Arabic dialects are therefore steerable mainly through distributed rather than localized representations
Title:Can Dialects Be Steered Like Languages? Sparse Neurons and Distributed Directions in Arabic LLMs
Abstract:Dialectal data are scarce relative to Modern Standard Arabic (MSA), causing Arabic LLMs to overproduce MSA and struggle with dialectally accurate generation. This raises a fundamental interpretability question about where and how dialectal features are encoded within model internals and whether these representations can improve dialect generation without fine-tuning. We study two inference-time approaches as interpretability probes and control mechanisms. First, neuron-level analysis identifies sparse populations that encode dialect-specific features and tests whether amplifying or suppressing them steers model outputs toward target dialects. Second, vector steering extracts dialect-specific activation directions and injects them during inference, motivated by feature entanglement at the neuron level. We find that these neurons are real but only partially explanatory. They occupy under 1\% of MLP dimensions but span only 5\% to 21\% of the residual dialect direction. This limited coverage is causally consequential. Neuron steering reinforces dialect in some varieties when the prompt is already dialectal but cannot induce it from MSA prompts, whereas vector steering succeeds in both settings. Arabic dialects are therefore steerable mainly through distributed rather than localized representations
Computation and Language (cs.CL)
arXiv:2607.03936 [cs.CL]
(or arXiv:2607.03936v2 [cs.CL] for this version)
https://doi.org/10.48550/arXiv.2607.03936 Focus to learn more arXiv-issued DOI via DataCite
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