This section describes how to use a mosaic plot to visualize the cells of a contingency table. A mosaic plot displays the frequency of data with respect to multiple nominal variables.

A mosaic plot is a set of adjacent bar plots formed first by dividing the horizontal axis according to the proportion of observations in each category of the first variable and then by dividing the vertical axis according to the proportion of observations in the second variable. For more than two nominal variables, this process can be continued by further horizontal or vertical subdivision. The area of each block is proportional to the number of observations it represents.