A boxplot summarizes the distribution of a continuous variable for several categories. If categories are organized in groups and subgroups, it is possible to build a grouped boxplot. Here is an example with R and ggplot2.
A grouped boxplot is a boxplot where categories are organized in groups and subgroups.
Here we visualize the distribution of 7 groups (called A to G) and 2
subgroups (called low and high). Note that the group must be called
in the X
argument of ggplot2
. The subgroup
is called in the fill
argument.
# library
library(ggplot2)
# create a data frame
variety=rep(LETTERS[1:7], each=40)
treatment=rep(c("high","low"),each=20)
note=seq(1:280)+sample(1:150, 280, replace=T)
data=data.frame(variety, treatment , note)
# grouped boxplot
ggplot(data, aes(x=variety, y=note, fill=treatment)) +
geom_boxplot()
Note that an alternative to grouped boxplot is to use faceting: each subgroup (left) or each group (right) is represented in a distinct panel.
👋 After crafting hundreds of R charts over 12 years, I've distilled my top 10 tips and tricks. Receive them via email! One insight per day for the next 10 days! 🔥