I have read the descriptions of mosaic plots in the book “R in Action” by Robert Kabakoff, [2], and one of the references provided in the book (“What is a mosaic plot?” by Steve Simon, [3]). I was impressed how informative mosaic plots are and I figured they can be relatively easily implemented using Prefix trees (also known as “Tries”) [4,5]. I implemented MosaicPlot while working on a document analyzing the census income data from 1998, [6]. This is the reason that data set is used in this document. A good alternative set provided by WL is ExampleData[{“Statistics”,”USCars1993”}].