Precision

• Precision

  Fraction of retrieved documents that are relevant; measures quality of retrieved set; high precision indicates few false positives.

• Measuring Search Effectiveness by Hand

  Before you tune a search system you need a way to know whether your changes made things better or worse. This guide shows you how to build a hand-crafted relevance judgement set — a spreadsheet of queries, documents, and expected rankings — and how to use it as a repeatable baseline.