What AI Can and Cannot Do – A Practical Guide By the end of this lesson, students should be able to: What hallucinations actually are. "Hallucination" in AI describes the phenomenon where a model generates specific, plausible-sounding claims that are simply wrong – invented. Not hedged, not qualified, not flagged as uncertain – just stated as fact. Examples of hallucination: Why hallucinations happen. The language model is predicting text, not retrieving verified facts. When asked about something it does not know well, it does not say "I don't know" – it generates text that looks like an answer. The generation process does not have a "confirm this exists before outputting it" step. The result is confident-sounding text describing things that are not real. Hallucination frequency varies by domain and task: Practical hallucination defenses. What bias means in AI. AI models learn from training data that reflects human writing – including the biases, perspectives, and underrepresentation in that writing. Several bias types appear in AI outputs: Representation bias: Groups, cultures, and perspectives underrepresented in training data are less fully or accurately represented in outputs. Common subjects, Anglophone perspectives, and majority-culture viewpoints are over-represented. Association bias: AI learns the associations present in training text. Stereotype-consistent associations may appear in generated content – in descriptions, examples chosen, roles assigned in generated scenarios. Perspective bias: AI may present mainstream or consensus views more fully than minority, contrarian, or non-Western perspectives – not because it was designed to, but because training data coverage is uneven. Practical bias management. Enroll to continue this lesson. The preview above shows the lesson objectives and opening lesson content. Enroll to view the full lesson, complete the practice work, and take the lesson quiz.
Lesson 4: Hallucinations, Bias, and Why AI Gets Things Wrong
Lesson Objectives
Lesson Content
