What does recall mean in Machine Learning?

Question

I know that the meaning of recall in search engine, but what\'s the meaning of recall of a classifier, e.g. bayes classifier? please give a an example, thanks.

for examp

Answer 1

In very simple language: For example, in a series of photos showing politicians, how many times was the photo of politician XY was correctly recognised as showing A. Merkel and not some other politician?

• precision is the ratio of how many times ANOTHER person was recognized (false positives) : (Correct hits) / (Correct hits) + (false positives)

• recall is the ratio of how many times the name of the person shown in the photos was incorrectly recognized ('recalled'): (Correct calls) / (Correct calls) + (false calls)