Use dplyr::percent_rank() to compute percentile ranks within group

Question

Suppose I have the following data:

id    grpvar1    grpvar2    value
1     1          3          7.6
2     1          2          4
...
3     1          5                 


        

Answer 1

Try:

 library(dplyr)
 dataf %>%
 group_by(grpvar1, grpvar2) %>% 
 mutate(percrank=rank(value)/length(value))