A relevance score is a numerical value assigned to a document that indicates how relevant that document is for a given query. Relevance scores are used to order results on an SERP, and can be calculated through a wide range of different relevance models. Relevance scores are distinguished from more rudimentary relevance models, such as binary relevance, which merely determines whether or not a document is relevant to query without assigning any score to the document.
Swiftype uses a proprietary relevance model to assign documents relevance scores as users perform queries. This allows Swiftype search engines to provide higher quality result sets immediately upon implementation.