Before even embarking on any numerical analyses, you may want to get a good idea about the data through a few quick plots. Although the base R system supports powerful graphics, we will generally turn to other plotting options like
ggplot for more advanced plots. Therefore, we cover only the simplest forms of basic graphs.
If you have not already done so, download the data files for this chapter and ensure that they are available in your R environment's working directory and run the following commands:
> auto <- read.csv("auto-mpg.csv") > > auto$cylinders <- factor(auto$cylinders, levels = c(3,4,5,6,8), labels = c("3cyl", "4cyl", "5cyl", "6cyl", "8cyl")) ...