library(tidyverse)
library(kableExtra)
df <- data.frame(
'time' = c(1, 2, 3, 1, 2, 3, 1, 2, 3),
'id' = c(1, 1, 1, 2, 2, 2, 3, 3, 3),
'score' = c(rnorm(9, 10, 2))
)
df <- df %>%
group_by(id) %>% mutate(lagscore = lag(score)) %>%
mutate(diffscore = score - lagscore)
df %>% kable() %>% kable_styling()
| time | id | score | lagscore | diffscore |
|---|---|---|---|---|
| 1 | 1 | 8.381000 | NA | NA |
| 2 | 1 | 9.016563 | 8.381000 | 0.6355627 |
| 3 | 1 | 10.187045 | 9.016563 | 1.1704821 |
| 1 | 2 | 8.388847 | NA | NA |
| 2 | 2 | 12.958878 | 8.388847 | 4.5700310 |
| 3 | 2 | 13.313880 | 12.958878 | 0.3550016 |
| 1 | 3 | 13.206961 | NA | NA |
| 2 | 3 | 10.130180 | 13.206961 | -3.0767809 |
| 3 | 3 | 8.783671 | 10.130180 | -1.3465091 |
Bo\(^2\)m =)