As briefly mentioned in chapter 1, the recall is a number between 0 and 1 equal to the number of documents that are retrieved and relevant, divided by the number of retrieved documents.

I'm not sure but it looks like the precision metrics.

According to the wikipedia page

for a text search on a set of documents, recall is the number of correct results divided by the number of results that should have been returned.

and

precision is the number of correct results divided by the number of all returned results