Recall and precision in the field of knowledge and information science in Persian article data bases and surveying overlap of them

The present study purpose is surveying the Recall and Precision and overlap in the databases such as Noormags, Magiran and Sid on the field ofknowledge and information science
Approach (Method): The research has been done as applied and survey approach. In order to surveying the amount of recall and precision and overlap in databases, the number 15 keywords was selected by consultation with professors. The keywords were searched in all three databases simultaneously. The first 10 results were retrieved at each database, their recall, precision and overlap calculated by the formula.
Finding: The result of research showed that Noormas with the %48 recall has the most amount of recall. Then, Sid and Magiran have respectively the %33 and %32 recall and have ranked the second and third. In terms of precision, Noormags with the %79 has the most amount of precision. Also, the result showed that Noormags with the %10 overlap in title and %72 overlap in information resources has the most amount of overlap with other databases.
The Noormags has a better performance in terms of recall and precision than other databases. This data bases have high overlap with other databases in terms of information resources. So, Noormags is the most appropriate database for all users in the field of knowledge and information science.