Recall = A/(A+D)

Proportion of documents relevant to a search question
that are retrieved by a given search formulation.

Precision = A/(A+B)

Proportion of documents retrieved by a given search
formulation that is relevant to the search question.

How to improve PRECISION

NARROW the search:

• Condense FACETS with fewer synonyms or more specific terms
• Add a new FACET
• Search in fewer SUBJECT FIELDS (Title, Abstract, Descriptors)
• Use more restrictive WORD OPERATORS

How to improve RECALL

BROADEN the search:

• Expand FACETS with more search terms
• Drop an existing FACET
• Search in more SUBJECT FIELDS (Title, Abstract, Descriptors)
• Use less restrictive WORD OPERATORS