Мы можем использовать quantile
library(doBy)
summaryBy(pd ~ industry + region + date, FUN=
function(x) c(Mean = mean(x), Quantile = quantile(x, probs = 0.75)), data=six_month_pd)
Используя воспроизводимый пример
data(warpbreaks)
out <- summaryBy(breaks ~ wool + tension, warpbreaks, FUN=function(x)
c(Mean = mean(x), Quantile = quantile(x, probs = .75)))
str(out)
#'data.frame': 6 obs. of 4 variables:
# $ wool : Factor w/ 2 levels "A","B": 1 1 1 2 2 2
# $ tension : Factor w/ 3 levels "L","M","H": 1 2 3 1 2 3
# $ breaks.Mean : num 44.6 24 24.6 28.2 28.8 ...
# $ breaks.Quantile.75%: num 54 30 28 31 39 21