Architectural Components

Trace a search query through rewriting, understanding, document selection, ranking, and blending. The design uses a funnel so that the more expensive ranking stages receive fewer documents.

Architecture

The diagram shows the request path and the feedback used to generate training data.

Each component answers a different question: what the user meant, which documents are candidates, how to order them, and which result types to display.

Query rewriting

Queries are often poorly worded and far from describing the searcher’s actual information needs. Hence, we use query rewriting to increase recall, i.e., to retrieve a larger set of relevant results. Query rewriting has multiple components which are mentioned below.

Spell checker