Editing Information retrieval (section)

== {{anchor|Precision}} Performance and correctness measures ==
{{main|Evaluation measures (information retrieval)}}
The evaluation of an information retrieval system' is the process of assessing how well a system meets the information needs of its users. In general, measurement considers a collection of documents to be searched and a search query. Traditional evaluation metrics, designed for [[Standard Boolean model|Boolean retrieval]]{{huh|date=June 2018}} or top-k retrieval, include [[precision and recall]]. All measures assume a [[ground truth]] notion of relevance: every document is known to be either relevant or non-relevant to a particular query. In practice, queries may be [[ill-posed]] and there may be different shades of relevance.