Graphics and Data Visualization
In Chapter 8, you learn how to graph and visualize data. As in other areas, R’s base graphics capabilities are fine for most day-to-day graphing purposes, but a number of packages extend R’s graphical functionality. We will use the ggplot2 package to illustrate.
The ggplot2 package was written by Hadley Wickham and Winston Chang as an implementation of the “grammar of graphics.” This term was introduced by Leland Wilkinson in his book on the subject published by Springer in 2005. The idea was to take the good parts of the base R graphics and lattice graphics, and none of the bad parts. All the graphics ...