Vertical position of stat_summary() in ggplot

Question

I am trying to do something like the first solution here:

give.n <- function(x){
   return(c(y = mean(x), label = length(x)))
}
ggplot(diamonds, aes(cut, price)) + 
   geom_boxplot() + 
   stat_summary(fun.data = give.n, geom = "text")

But I want those sample sizes to be displayed at position y = 0, not in the boxes of the boxplots. How do I do this?

Answer 1

The function give.n() returns both, the y-coordinate at which to display the number and the number to be displayed (i.e., the label). You simply need to change the y-coordinate returned by give.n():

give.n <- function(x){
   return(c(y = 0, label = length(x)))
}