Graphics for Categorical Data
This chapter describes plots for categorical data. Some of these plots can be produced using traditional, lattice, or ggplot2 functions, but the vcd package provides both specializations and generalizations that go beyond the facilities provided by the core graphics packages.
This chapter focuses on graphics for visualizing categorical data. Although categorical data are extremely common, the techniques for visualizing categorical data, especially in a multivariate setting, are much less well known than the corresponding plot types for continuous variables. For example, the mosaic plot for displaying the relationship between two categorical variables is much less common than the ubiquitous ...