Hello,
I have a dataset with student performance on a math test. There are
multiple cases for each student (identified by id) and the concept as a
variable.
> rtest
id test subject grade concept correct tested per_corr
year
1 1 83 Mathema 8 8.2.D 1 1 100
2011
2 1 83 Mathema 8 8.3.A 1 2 50
2011
3 1 83 Mathema 8 8.3.B 2 2 100
2011
4 1 83 Mathema 8 8.4 2 2 100
2011
5 1 83 Mathema 8 8.5.A 1 2 50
2011
6 1 83 Mathema 8 8.5.B 0 2 0
2011
7 2 83 Mathema 8 8.2.D 1 1 100
2011
8 2 83 Mathema 8 8.3.A 2 2 100
2011
9 2 83 Mathema 8 8.3.B 1 2 50
2011
10 2 83 Mathema 8 8.4 2 2 100
2011
11 2 83 Mathema 8 8.5.A 1 2 50
2011
12 2 83 Mathema 8 8.5.B 0 2 0
2011
I would like to make a variable for each concept (e.g. 8.2D, 8.3.A, 8.3B)
and then put that percentage correct currently under per_corr for that
variable.
Such as
id test subject grade 8.2D 8.3.A 8.3.B
year
1 1 83 Mathema 8 100 50 100
2011
2 2 83 Mathema 8 100 100 50
2011
Does anybody have an effcient way of doing this?
What trips me up is handling the variables such as test and subject.
Thank you,
James
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