Telling Stories with Data - Data Points: Visualization That Means Something - page 11

Relationships

Have you ever seen a graphic with a whole bunch of charts on it that
seemed like they've been randomly placed? I'm talking about the graph-
ics that seem to be missing that special something, as if the designer gave
only a little bit of thought to the data itself and then belted out a graphic to
meet a deadline. Often, that special something is relationships.

In statistics, this usually means correlation and causation. Multiple vari-
ables might be related in some way. Chapter 6, “Visualizing Relation-
ships,” covers these concepts and how to visualize them.

 The World
Progress Report
was a graphi-
cal report that
compared prog-
ress around the
world using data
from UNdata. See
the full version at
http://datafl
.ws/12i.

At a more abstract level though, where you're not thinking about equations
and hypothesis tests, you can design your graphics to compare and con-
trast values and distributions visually. For a simple example, look at this
excerpt on technology from the World Progress Report in Figure 1-8.

These are histograms that show the number of users of the Internet,
Internet subscriptions, and broadband per 100 inhabitants. Notice that the
range for Internet users (0 to 95 per 100 inhabitants) is much wider than
that of the other two datasets.

FIGurE 1-8 Technology adoption worldwide