AI engineering glossary · Evaluation metrics
What is ARI (Adjusted Rand index)?
Adjusted Rand index (also called ARI): A measure of agreement between two ways of grouping the same items, such as clusters versus true classes, that counts pairs placed together or apart in both and corrects for chance. It is 1 for identical groupings, about 0 for random ones, and can be negative.
Adjusted Rand index: an example
K-means clusters of 1,000 customers are compared with known segments; an ARI of 0.72 indicates strong agreement well beyond chance.
Related terms
More Evaluation metrics terms
Where you learn it
Adjusted Rand index is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.