Reranking applies a second, more computationally intensive model to score the top results from an initial retrieval pass. The initial pass optimizes for recall across a large index, while reranking optimizes precision among the candidates.

It is a standard component of production retrieval systems.

Alternative Names:

Rerank, Result Reranking

Why it Matters?

Reranking addresses the practical constraint that only a limited number of passages fit in a model's context. If the genuinely relevant passage ranks twentieth and only the top five are supplied, the answer will be wrong regardless of model quality. In matters with large document sets, reranking quality is frequently the difference between an accurate answer and a confident wrong one.

Frequently Confused with

Related terms

Frequently asked questions

Why is reranking necessary?

Why is reranking necessary?

Because only a limited number of passages fit in the context window, so ordering matters. A relevant passage ranked too low never reaches the model.

How does it differ from initial retrieval?

How does it differ from initial retrieval?

Initial retrieval favors recall across a large index quickly. Reranking applies a more precise and expensive model to a small candidate set.