6.1 6.2 Grouped and stacked bars

• Plot a quantitative variable versus a categorical variable split by another categorical variable via an aesthetic (e.g. colour)

• Which categorical variable is assigned to the axis vs. the aesthetic affects messaging

• Grouped bars are plotted side by side and stacked bars are plotted one on top of the other

• Facetting is another approach that avoids scaling a categorical variable via an aesthetic

• Simple bar charts can convey a message without axes labels for the quantitative variable