Groups

The focus of this chapter is the representation of sets of data of a continuous or discrete variable (the target variable) across levels of a categorical or numerical discrete variable (the group variable). There are a variety of choices, and the selection primarily depends on the degree of data aggregation desired for the visualization. We describe how to show every data point in each group through strip plots or swarm plots, to display summary statistics of each group by box plots, or to visualize the overall frequency distribution via violin plots. The chapter also describes how to combine the above plots in various ways, for instance by overlapping strip plots with box plots and violin plots with box plots.