create a boxplot in R that labels a box with the sample size (N)

Question

Is there a way to create a boxplot in R that will display with the box (somewhere) an \"N=(sample size)\"? The varwidth logical adjusts the width of the box on the basis of sam

Answer 1

Here's some ggplot2 code. It's going to display the sample size at the sample mean, making the label multifunctional!

First, a simple function for fun.data

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

Now, to demonstrate with the diamonds data

ggplot(diamonds, aes(cut, price)) + 
   geom_boxplot() + 
   stat_summary(fun.data = give.n, geom = "text")

You may have to play with the text size to make it look good, but now you have a label for the sample size which also gives a sense of the skew.