R in Action, Third Edition

4 Getting started with graphs

This chapter covers

• Introducing the ggplot2 package
• Creating a simple bivariate (two-variable) graph
• Using grouping and faceting to create multivariate graphs
• Saving graphs in multiple formats

On many occasions, I’ve presented clients with carefully crafted statistical results in the form of numbers and text, only to have their eyes glaze over while the chirping of crickets permeated the room. Yet those same clients had enthusiastic “Ah-ha!” moments when I presented the same information to them in the form of graphs. Often, I can see patterns in data or detect anomalies in data values by looking at graphs—patterns or anomalies that I completely missed when conducting more formal statistical analyses.

Human beings ...