r - dplyr 按值组采样

Question

我想使用 dplyr 根据分组值制作样本:

我试过的:

 id <- c(1, 1, 1, 2, 3, 3, 4, 5, 5, 5, 6, 6, 7, 8, 8, 8, 8, 8)

 id <-  as.data.frame(id)

 sample <- id %>%
   group_by(id) %>%
   sample_n(2, replace = FALSE) %>%
   ungroup(id)

sample

预期结果(n样本=2):

1, 1, 1, 2

或

1, 1, 1, 3, 3

或

5, 5, 5, 6, 6

等等

我有一个错误:

Error: `size` must be less or equal than 1 (size of data), set `replace` = TRUE to use sampling with replacement

Answer 1

也许这有帮助

id %>% 
  distinct(id) %>% 
  sample_n(2, replace = FALSE) %>% 
  inner_join(id, .)