In the field of information retrieval, precision is the fraction of retrieved documents that are relevant to the query:

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For example, for a text search on a set of documents, precision is the number of correct results divided by the number of all returned results.

Precision takes all retrieved documents into account, but it can also be evaluated at a given cut-off rank, considering only the topmost results returned by the system. This measure is called "precision at n" or "P@n".

Precision is used with recall, the percent of "all" relevant documents that is returned by the search. The two measures are sometimes used together in the F1 Score (or f-measure) to provide a single measurement for a system.

Note that the meaning and usage of "precision" in the field of information retrieval differs from the definition of accuracy and precision within other branches of science and technology.

সংগা (ইনফরমেশন রিট্রিভাল কনটেক্সট))
Limitations as goals
প্রিসিশন
Probabilistic interpretation