Creat data label for geom_count

Question

I am really new to R, and I am now practicing making data visualizations with the "palmerpenguins" package: I have made the following plot to check the distributions of penguins based on their species and islands:

ggplot(data=penguins_raw,mapping=aes(x=Species,y=Island))+
  geom_count(aes(color=after_stat(n)))

However, I would also like to add the data labels to show the count of penguins of each species/island. I understood that I should use the "geom_text" function, but I have tried but could not write the function correctly. Really appreciate your help!

The functions I have tried include: #1:

ggplot(data=penguins_raw,mapping=aes(x=Species,y=Island))+
  geom_count(aes(color=after_stat(n)))+
  geom_text(aes(label=n,color = "#ffffff"))

#2:

ggplot(data=penguins_raw,mapping=aes(x=Species,y=Island))+
  geom_count(aes(color=after_stat(n)))+
  geom_text(aes(label=after_stat(n),color = "#ffffff"))

but obviously I am not writting the correct function.

Answer 1

The issue is that geom_count uses stat="sum" under the hood to compute the "counts", whereas the stat defaults to "identity" for geom_text. Instead, if you want to add the counts displayed by geom_count to your chart you have use stat="sum" for geom_text too. Only then can you use after_stat to display the counts as labels:

library(ggplot2)
library(palmerpenguins)

ggplot(data = penguins_raw, mapping = aes(x = Species, y = Island)) +
  geom_count(aes(color = after_stat(n))) +
  geom_text(aes(label = after_stat(n)),
    color = "#ffffff",
    stat = "sum"
  )