I need your kind help typing data using R. A sample of my original data looks like this:
> dput(mydata1)
structure(list(subject = c("E1", "E1", "E1", "E1", "E1", "E1",
"E1", "E1", "E1", "E1", "E1", "E1"), block = c(3, 3, 3, 4, 4,
4, 5, 5, 5, 6, 6, 6), condition = c("EI", "EI", "I", "EI", "EI",
"I", "EI", "EI", "I", "EI", "EI", "I"), RT = c(271, 370, 469,
409, 560, 1506, 544, 544, 978, 452, 340, 645), Item_number = c(1,
2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3)), row.names = c(NA, -12L), class = c("tbl_df",
"tbl", "data.frame"))
> mydata1
# A tibble: 12 x 5
subject block condition RT Item_number
<chr> <dbl> <chr> <dbl> <dbl>
1 E1 3 EI 271 1
2 E1 3 EI 370 2
3 E1 3 I 469 3
4 E1 4 EI 409 1
5 E1 4 EI 560 2
6 E1 4 I 1506 3
7 E1 5 EI 544 1
8 E1 5 EI 544 2
9 E1 5 I 978 3
10 E1 6 EI 452 1
11 E1 6 EI 340 2
12 E1 6 I 645 3
I am trying to compare RT value for condition EI in block 3 with RT values for condition I in block 3, 4, 5, and 6. So, for the purpose of the research question I am trying to address, I am considering all RT values for condition I while I am only considering the RT value for condition EI in block 3. To make the comparison easy to read by R, I would like to replace the RT values for condition EI in block 4, 5 and 6 by the RT value of the same condition in block 3.
So, if the condition is EI and the block is either 4,5,6: then, the RT value for this condition in that block for that Item_number and subject should be equivalent to the RT value for the same condition, Item_number, and subject in block 3. This should work for condition EI across each subject and Item_number.
The desired output should be something like this:
> dput(data2_cleaned)
structure(list(subject = c("E1", "E1", "E1", "E1", "E1", "E1",
"E1", "E1", "E1", "E1", "E1", "E1"), block = c(3, 3, 3, 4, 4,
4, 5, 5, 5, 6, 6, 6), condition = c("EI", "EI", "I", "EI", "EI",
"I", "EI", "EI", "I", "EI", "EI", "I"), RT = c(271, 370, 469,
271, 370, 1506, 271, 370, 978, 271, 370, 645), Item_number = c(1,
2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3)), row.names = c(NA, -12L), class = c("tbl_df",
"tbl", "data.frame"))
> data2_cleaned
# A tibble: 12 x 5
subject block condition RT Item_number
<chr> <dbl> <chr> <dbl> <dbl>
1 E1 3 EI 271 1
2 E1 3 EI 370 2
3 E1 3 I 469 3
4 E1 4 EI 271 1
5 E1 4 EI 370 2
6 E1 4 I 1506 3
7 E1 5 EI 271 1
8 E1 5 EI 370 2
9 E1 5 I 978 3
10 E1 6 EI 271 1
11 E1 6 EI 370 2
12 E1 6 I 645 3
I would greatly appreciate your kind help and thoughts in how to achieve the desired output.
CodePudding user response：
You could try the following with dplyr. After grouping by subject and Item_number, check to see if the block is 4-6 and condition is "EI" - if so, change the RT value to the one where block is 3.
library(dplyr)
mydata1 %>%
group_by(subject, Item_number) %>%
mutate(RT = ifelse(block %in% 4:6 & condition == "EI", RT[block == 3], RT))
Output
subject block condition RT Item_number
<chr> <dbl> <chr> <dbl> <dbl>
1 E1 3 EI 271 1
2 E1 3 EI 370 2
3 E1 3 I 469 3
4 E1 4 EI 271 1
5 E1 4 EI 370 2
6 E1 4 I 1506 3
7 E1 5 EI 271 1
8 E1 5 EI 370 2
9 E1 5 I 978 3
10 E1 6 EI 271 1
11 E1 6 EI 370 2
12 E1 6 I 645 3