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AI hallucinations

September 10, 2025
Generative technology is now widely used in healthcare, finance, education, media, and the arts. It helps reduce costs, improve efficiency, and support creativity—for example, assisting with medical image analysis or producing design content. Alongside these benefits, however, its rapid growth has also raised concerns about accuracy and reliability, one of which is AI hallucinations.

What are AI hallucinations?

AI hallucinations are instances where an AI system generates a response that is factually incorrect, nonsensical, or unrelated to the provided context, yet presents it as if it were true. This term is a metaphor drawn from human psychology, where a hallucination is a false perception. However, unlike human hallucinations, which are often a result of neurological or psychological conditions, AI hallucinations are a by-product of how the models are designed and trained.

Why do AI hallucinations happen?

AI hallucinations are a significant challenge in generative artificial intelligence, where a model generates information that is factually incorrect, illogical, or not based on its training data. Research indicates that up to 30% of AI-generated content can contain misleading information. This issue does not come from an intention to mislead, but from the fundamental way these systems operate. As a result, AI hallucinations remain one of the most pressing limitations of generative models. Rather than verifying facts, AI models generate responses by predicting the most probable sequence of words based on learned patterns.

There are several key issues that contribute to the phenomenon of AI hallucination:

Training data limitations

AI models learn from extensive datasets that can contain inaccuracies, biases, or outdated information. When a query involves a topic with incorrect training data, the model may invent information to generate a seemingly full response, even if the details are not based on the actual data.

Vague prompts

The clarity of a prompt directly shapes the quality of the response. When a question is vague or overly complicated, the system may misinterpret what is being asked. To fill the gaps, it might add invented details in order to sound complete, which can result in information that looks convincing but is actually inaccurate.

Mixed information

Generative systems are skilled at drawing from many sources, but sometimes they combine details incorrectly. Approximately 40% of AI-generated content shows evidence of mixed information, where details from separate documents or datasets are combined in ways that do not belong together. For example, the name of one researcher might be paired with the findings of another, or statistics from different studies may be presented as if they came from the same source.

Lack of factual verification

These systems are built to generate confident, well-structured text, which can make mistakes hard to recognize. Unlike a human fact-checker, they cannot cross-reference details with real-time or external sources. Instead, they depend only on the information contained in their training data. If that data is limited or outdated, the response may still sound convincing while being inaccurate.

How to avoid AI hallucinations?

Preventing AI hallucinations is a key challenge, but users can significantly reduce their likelihood by employing a number of strategies. These methods focus on providing the AI with better information and structure, as well as on a greater degree of human oversight.

These techniques are based on how you interact with the AI model. By improving your prompts and how you evaluate the output, you can improve accuracy:

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Provide context and specifics

The more context you give the AI, the better the response. Instead of a vague request like, “Write about climate change,” give specifics: “Write a 200-word summary of climate change causes from 2000 to 2020, using data from the Intergovernmental Panel on Climate Change (IPCC).”

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Request citations

Even when sources are cited, it’s important to verify them yourself. Verifying information yourself helps ensure accuracy and avoid mistakes. This is especially important for tasks where decisions depend on correct information or where mistakes could have negative consequences.

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Fact-check everything

AI-generated responses can sometimes be inaccurate or contain misleading information. For important tasks, always double-check key facts, figures, and statements using authoritative sources to prevent reliance on insufficient data, which may influence decisions.

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Simplify complex queries

Large or multi-step questions can increase mistakes in AI outputs. Breaking a problem into smaller, focused steps makes it easier to handle each part carefully, improving overall response quality and reducing mistakes in reasoning or interpretation.

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Specify a factual source

Encourage the AI to base its responses on reliable sources whenever possible. Phrases like ‘According to the U.S. Census Bureau…’ or ‘Based on the article provided…’ help ensure answers are supported by verifiable data, reducing the chance of inaccuracies.

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Provide clear output instructions

Clearly indicate how you want the AI to present information, whether in a list, table, or short paragraph. For example, asking, “List three key benefits of exercise in bullet points,” ensures organized, readable, and professional outputs that meet your requirements.

Intern Content Marketing
Marija is a 21-year-old content marketing intern in Zwolle, originally from Lithuania. She’s in her final year of a Creative Business bachelor’s at NHL Stenden University. She loves writing and creating content for social media, but she’s also curious about the bigger world of digital marketing and enjoys picking up new skills along the way. Maria’s international background makes her adaptable and open-minded, always ready to bring fresh ideas to every project. Outside of work, Maria loves animals. She’s more of a cat person, but she also likes dogs, so she feels right at home in our dog-friendly office :)
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