In statistics' confusion matrix, why does 'recall' have that name?

Question

There are a number of words used very frequently to describe properties of a confusion matrix (or contingency table).

Among them there is the word 'recall', this is to describe:

tp
 ―――――
 tp+tf

which means, the rate of your predicted positive instance out of the real true instance number (the true positives plus false negatives).

But this was given the name recall, which has confused me a lot.

After some digging within Cambridge Dictionary, I found that 'recall' sounds to me like you have your memory back and then you think of something you might have forgotten. Another is to describe how you want something you already sent out back.

So why can recall the word be used to describe the confusion matrix rate? When (and by who) was the first use of 'recall' in this way?

Greybeard · Answer

https://en.wikipedia.org/wiki/Precision_and_recall has

Suppose a computer program for recognizing dogs in photographs identifies 8 dogs in a picture containing 12 dogs and some cats. Of the 8 identified as dogs, 5 actually are dogs (true positives), while the rest are cats (false positives). The program's precision is 5/8 while its recall is 5/12.

In this case "to recall" has the meaning of "to return to the originator; to order/command the return of someone or something" as in "In January, he was appointed Ambassador to Ruritania, but was recalled in March."
OED:
2. a. transitive. To call back or summon (a person, or figurative a thing) to return to or from a place; to restore (a person) to a former position or occupation, membership of a team, etc.
1961   D. Heller & D. Heller Kennedy Cabinet iv. 69   Impressed by Dillon's skill and breadth of economic experience, Secretary Dulles recalled him to Washington.
2003   Bang Apr. 38/1   In time, the mysterious Frankie Poullain was recalled from Venezuela to add the bass.
b. transitive. Without reference to physical location: to bring back (a thing or person) by or as by a call.
1854   Capt. Rafter tr. A. de Lamartine Hist. Restoration Monarchy in France (new ed.) IV. xli. 134   He burned with impatience to return to the great political stage, and to recall absent attention to himself once more, by going back to France.
2000   G. Cook Soldiers Live 1   We were supernatural, many recalled from the dead, the ultimate Stone Soldiers.

seshadri Gopalakrishnan · Answer

Wikipedia on Recall and Precision clearly tells us what these terms mean. Recall is the proportion of relevant items retrieved among those that should have actually been retrieved. hence recall.

In statistics' confusion matrix, why does 'recall' have that name?

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