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arXiv · 2512.22778

Fake News Classification in Urdu: A Domain Adaptation Approach for a Low-Resource Language

Muhammad Zain Ali·Bernhard Pfahringer·Tony Smith
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Abstract

Misinformation on social media is a widely acknowledged issue, and researchers worldwide are actively engaged in its detection. However, low-resource languages such as Urdu have received limited attention in this domain. An obvious approach is to utilize a multilingual pretrained language model and fine-tune it for a downstream classification task, such as misinformation detection. However, these models struggle with domain-specific terms, leading to suboptimal performance. To address this, we investigate the effectiveness of domain adaptation before fine-tuning for fake news classification in Urdu, employing a staged training approach to optimize model generalization. We evaluate two widely used multilingual models, XLM-RoBERTa and mBERT, and apply domain-adaptive pretraining using a publicly available Urdu news corpus. Experiments on four publicly available Urdu fake news datasets show that domain-adapted XLM-R consistently outperforms its vanilla counterpart, while domain-adapted mBERT exhibits mixed results.

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Muhammad Zain Ali, Bernhard Pfahringer, Tony Smith. 2025-12-28. Fake News Classification in Urdu: A Domain Adaptation Approach for a Low-Resource Language. https://arxiv.org/abs/2512.22778

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