If you review after the test, your memory is further enhanced. In the psychologist Karpicke and Blunt's experiments (*18), 80 college students have read the texts related to science and conducted a test to test their understanding in a week. Subjects were divided into three groups, and each studied in different ways. (*19)

Onetime learning group: Groups that read the texts only once

Repeated learning group: Groups that read the texts 4 times

Recalling group: Group that

read textbooks once,

try to recall,

then read the texts again,

and try to recall.

The accuracy rate of the onetime learning group was about 30%, and the repeated learning group was higher than that by about 50%. This difference is nothing special that memory by reading four times is stronger than reading once. However, what is important is the record of the recalling group. This group had an even higher 70% correct answer rate. Rather than repeating the input 4 times, it was better to use a part of the time for the tests.

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Footnotes:

*18 Karpicke, J.D. and Blunt, J.R., 2011. Retrieval practice produces more learning than elaborative studying with concept mapping. Science, 331(6018), 772-775.

*19 In the experiments, there is the fourth group to draw the "concept map" while reading texts, but I omit it because there are no noticeable results.