What is Hallucination?

Hallucination

Definition When an AI model generates text that is factually incorrect, fabricated, or unsupported by its input, while presenting it with apparent confidence. Hallucination is a fundamental reliability challenge for large language models.

In Depth

Hallucinations occur because LLMs are trained to produce fluent, plausible token sequences rather than verified facts. Common forms include invented citations, incorrect dates, fabricated statistics, and nonexistent people or products. Mitigation strategies include RAG, grounding with external tools, chain-of-thought prompting, and confidence calibration. Hallucination rates are a key metric when evaluating LLMs for high-stakes applications.

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AI Agent AI Alignment Agentic AI Artificial General Intelligence Artificial Superintelligence Attention Mechanism AutoML Benchmark Bias (AI) Chain-of-Thought Computer Vision Deepfake Diffusion Model Edge AI Embedding Federated Learning Few-Shot Learning Fine-Tuning Function Calling GPT