根据另一列中的共识值替换列中的 NAs 值

Question

我有一个数据框，例如:

Groups Event Value
G1     1     Canidae
G1     1     Canidae
G1     1     Felidae
G1     1     NA
G1     2     Felidae
G1     2     NA
G1     2     NA 
G1     2     Felidae
G1     3     NA
G2     1     NA
G2     1     NA
G3     1     Lemuridae
G3     2     NA 
G3     3     Lemuridae 
G4     1     Felidae
G4     1     Felidae
G4     1     unknown
G5     1     unknown
G5     1     Felidae

我想在每个 Groups 和 Event 中根据共识值，比如G1 Event1中有一个NA，那么共识值就是Canidae，所以我将 NA 替换为 Canidae

最后我应该得到:

Groups Event Value
G1     1     Canidae
G1     1     Canidae
G1     1     Canidae
G1     2     Felidae
G1     2     Felidae
G1     2     Felidae
G1     2     Felidae
G1     3     NA
G2     1     Lemuridae
G2     1     Lemuridae
G3     1     Lemuridae
G3     2     NA 
G3     3     Lemuridae 
G4     1     Felidae
G4     1     Felidae
G4     1     Felidae
G5     1     Felidae
G5     1     Felidae

有人有想法吗？非常感谢您的宝贵时间。

数据如下:

structure(list(Groups = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 1L, 
1L, 1L, 2L, 2L, 3L, 3L, 3L, 4L, 4L, 4L), .Label = c("G1", "G2", 
"G3", "G4"), class = "factor"), Event = c(1L, 1L, 1L, 1L, 2L, 
2L, 2L, 2L, 3L, 1L, 1L, 1L, 2L, 3L, 1L, 1L, 1L), Value = structure(c(1L, 
1L, 2L, NA, 2L, NA, NA, 2L, NA, NA, NA, 3L, NA, 3L, 2L, 2L, 4L
), .Label = c("Canidae", "Felidae", "Lemuridae", "unknown"), class = "factor")), class = "data.frame", row.names = c(NA, 
-17L))

Answer 1

我们可以按模式进行分组

library(dplyr)
df1 %>%
   mutate(Value = as.character(Value)) %>%
   group_by(Groups, Event) %>%
   mutate(Value = replace(Value, is.na(Value)|Value %in% "unknown", 
         Mode(Value[Value != "unknown"])))

在哪里

Mode <- function(x) {
  ux <- unique(x)
  ux[which.max(tabulate(match(x, ux)))]
}