AI engineering glossary · RAG vector search
What is ANN recall?
ANN recall: The fraction of the true nearest neighbours that an approximate index actually returns, measured against exact search results. It quantifies the accuracy lost for speed, and must be reported with the latency at which it was achieved.
ANN recall: an example
An index returning 9 of the true 10 nearest vectors has recall@10 of 0.9.
Related terms
More RAG vector search terms
- Answer correctness
- Answer relevance
- Approximate nearest neighbour search
- Asymmetric search
- Attribution
- Binary quantisation
- Chunk
- Chunk overlap
Where you learn it
ANN recall is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.