During the pandemic, the wave of COVID-19 fake news spread as fast as the virus itself, hitting even languages less present in the digital world, like Romanian. To stem the tide, a research team built a brand-new Romanian dataset, collecting virus-related fake articles and sorting them into "super-narratives": major recurring themes like anti-vax propaganda, conspiracy theories, or blaming foreign powers.
The challenge was teaching an AI to spot them automatically. They tested several Large Language Models (LLMs), including LLaMA 3.1 8B, trying four strategies: from zero-shot learning (no examples) to few-shot (a handful of examples), up to classic supervised learning. The real breakthrough came with semi-supervised learning: the model studies a mountain of unlabeled text to grasp the language, then fine-tunes its aim on a few human-guided cases. The result? An F1-score of 78.81%, beating old classifiers based on grammar and syntax.
This approach is a breath of fresh air for "low-resource languages", often ignored by major systems. It also paves the way for real-time fact-checking and transparent explanations: the AI doesn't just say "it's false", but shows why and with which arguments to counter it. A step forward for healthier information, in any language.
