Annotate points of a geom_boxplot, that fulfill specified conditions?

Say I have a boxplot that I created per ggplot(). And this boxplot has points above the upper whisker and below the lower whisker. If I desire to comment only a subset of those points, for example, only points, that correspond to variable values 50 and above or 5 and below. How would I do that?


For clarification: Instead of commenting and point out, that specific
points are above or below a specified threshold, I meant commenting each point individually, like labelling the points that are above and below the threshold with their respective value. So if a value like 70 is above the upper threshold of 50, I’d like the point to be annotated directly next to it with "70".

>Solution :

I would overplot some points in a new geom_point layer using a distinct color by passing the appropriate subset of the data, then add text labels with the same subset.

df <- data.frame(x = 'Data', y = rnorm(1000, 26, 7))


ggplot(df, aes(x, y)) + 
  geom_boxplot() +
  ylim(c(0, 60)) +
  geom_point(data = subset(df, y > 50 | y < 5), color = 'red') +
  geom_text(data = subset(df, y > 50 | y < 5), aes(label = round(y, 2)),
            nudge_x = 0.08)

enter image description here

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