Glossary term
Glossary term
Evaluation and Benchmarks
The percentage of claims in a response that aren't grounded. For example, if an LLM's response makes 10 claims but only 1 is grounded, the UCR is 90%.
A high UCR implies that an LLM is hallucinating too frequently.
See also citation precision and citation recall.
Created for this library
A factuality evaluation team monitors unsupported claim rate on generated summaries to detect grounding regressions before release.
A legal-tech vendor reports unsupported claim rate on its contract summaries so reviewers see how often claims lack a citation.
An LLM safety team uses unsupported claim rate alongside groundedness as part of release gating.
Definition source: Google for Developers Machine Learning Glossary | Creative Commons Attribution 4.0 License