Output Evaluation and Validation·Task 2.2·Bloom: remember·Difficulty 1/5·5 min read·Updated 2026-07-14

The Three Signatures of AI Hallucination

Identify hallucinations, inconsistencies, and biases in responses

SUBy Solomon UdohReviewed by Solomon UdohAI-assisted · human-reviewed
In short
The hallucination taxonomy names three signatures of AI-generated inaccuracy: plausible-but-unsupported claims that sound reasonable but have no basis in fact or source, fabricated specifics such as invented statistics, dates, names, or citations that read as authoritative because they are precise, and confident tone that does not track actual certainty. Fluent writing quality is not a reliable indicator of correctness for any of the three.

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