A brief peek at ggplot2

Tufte (2001) and Wilkinson (2005) emphasize the aesthetics of graphics a lot. There is indeed more to graphics than mere mathematics, and the subtle changes/corrections in a display may lead to an improved, enhanced, and pleasing feeling on the eye diagrams. Wilkinson emphasizes on what he calls grammar of graphics, and an R adaptation of it is given by Wickham (2009).

Thus far, we have used various functions, such as barchart, dotchart, spineplot, fourfoldplot, boxplot, plot, and so on. The grammar of graphics emphasizes that a statistical graphic is a mapping from data to aesthetic attributes of geometric objects. The aesthetics aspect consist of color, shape, and size, while the geometric objects are composed of points, lines, and bars. A detailed discussion of these aspects is unfortunately not feasible in this book, and we will satisfy ourselves with a quick introduction to the grammar of graphics. To begin with, we will simply consider the qplot function from...