Hi all,
i'm trying to run a two-sample t-test.
i have a longitudinal data that looks like this:
idn age class
1 22 1
1 22 1
1 22 1
1 22 1
2 63 3
2 63 3
2 63 3
3 43 2
3 43 2
3 43 2
3 43 2
3 43 2
3 43 2
4 37 1
4 37 1
4 37 1
.
.
.
i want to compare between class 1 and 3, to see if there are any age
differences, and want to count every id once (not all id numbers have the
same number of rows).
i tried:
with(
subset(x1, !duplicated(idn)),
t.test(age[class=="1"],age[hidclass=="3"]
)
but it didn't work. any suggestions?
thank you,
sigalit.
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