What is Document frequency?

Document frequency is the number of times a given term or query appears in a specific document within a larger search index. Document frequency is an important measurement for determining how relevant a particular document is for a given query, and is an essential piece of the widely used TF-IDF relevancy algorithm.

In Swiftype

Swiftype Site Search and App Search use document frequency, along with a host of other full text search and language analysis tools, to provide highly relevant results for user-generated queries.