Reference

AI Hallucination Examples

A categorized reference of documented AI hallucination types — what they are, how they occur, and why they matter.

Citation Fabrication

AI models generate plausible-looking references — complete with author names, journal titles, publication years, and DOIs — that don't correspond to real published works. The citations pass superficial formatting checks but fail verification against actual databases.

Fake journal articles in research summaries
High impact

When asked to summarize the research landscape on a topic, AI tools will sometimes populate reference lists with papers whose titles, authorship, and journal placement are all generated rather than retrieved from actual publication databases.

Invented book chapters and page numbers
Medium impact

Specific chapter titles and page ranges are generated to match what 'should' exist given a book's stated scope — even when the book itself is real but the specific sections don't exist.

Knowledge Cutoff Errors

AI models have a training data cutoff, beyond which they have no direct knowledge. Rather than clearly acknowledging the limit, they sometimes present pre-cutoff information as current, or conflate different time periods without indicating uncertainty.

Outdated leadership and organizational information
Medium impact

AI tools frequently state current executives, department heads, or organizational structures from their training data period — without flagging that the information may have changed. This is particularly common for government positions and technology company leadership.

Superseded research findings
High impact

Scientific findings that were widely cited at the time of training but have since been challenged, retracted, or superseded may be presented as current consensus without caveat.

Outdated pricing, features, and product specifications
Medium impact

Software pricing, API limits, hardware specifications, and product features change frequently. AI tools trained before a major product revision will state outdated specifications with no indication of the time gap.

Laws and regulations that have since changed
High impact

Statutory requirements, regulatory thresholds, and procedural rules that were in force during the training period may be presented as current law — even when subsequent amendments have changed the applicable rules.

Reasoning Drift and Confabulation

AI models sometimes construct responses where the chain of reasoning appears internally consistent but contains factual errors introduced mid-argument — each inference 'makes sense' given the previous statement, but the underlying premise was wrong.

Compounding numerical errors in analysis
High impact

An AI may state a statistic correctly, then apply a formula to it correctly, then arrive at a wrong conclusion because the initial statistic was subtly wrong. The final answer inherits and amplifies the original error.

Correct process, wrong specific data
Medium impact

When explaining how something works, AI tools often get the conceptual process correct while filling in specific data points (dates, names, numbers) with plausible but inaccurate values.

Cross-domain concept conflation
Medium impact

A term or concept from one field may be applied using the rules of another field — particularly where the same word has different technical meanings in different disciplines (e.g., 'hazard' in epidemiology vs. engineering vs. insurance).

Biographical and Factual Person Errors

Biographical information about real individuals — particularly those who are real but not extensively documented — is frequently confabulated. Birth dates, affiliations, achievements, and quotes get assigned to the wrong person or invented entirely.

Invented quotes attributed to real people
High impact

AI tools will generate quotes in a person's documented 'style' and attribute them to that person. The person is real; the quote is not. This is particularly common for academics, historical figures, and public intellectuals.

Wrong credentials and affiliations
Medium impact

Professional credentials, institutional affiliations, and academic titles are frequently wrong for individuals who are real but not extensively covered by online sources. The model 'fills in' plausible-sounding credentials.

Merged individuals
Medium impact

Where two or more people share a name or are closely associated in training data, biographical details from one may be attributed to another — creating a composite profile that accurately describes neither individual.

Technical Specification Errors

In technical contexts — code, APIs, hardware, specifications — AI tools produce plausible-sounding but incorrect specifics. Functions, parameters, version numbers, configuration syntax, and endpoint names are particularly prone to this.

Non-existent API methods and parameters
High impact

An AI will describe a function that logically should exist in a library, complete with a plausible name, parameter list, and return type — when the function doesn't exist. The pattern fits the library's naming conventions, which makes the error harder to spot.

Deprecated syntax presented as current
High impact

Code patterns that were standard in an older framework version continue to appear in AI responses after the library has shipped a breaking change. The code runs without error in old versions and silently fails in current ones.

Wrong version-specific behavior
Medium impact

Behavior that changed across versions — default values, configuration option names, module paths — is often stated without version qualification, leading to version-specific bugs that can be difficult to trace.

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