Telling Stories with Data - Data Points: Visualization That Means Something - page 16

As you can see, plenty of options are available to you. They're easy to use,
but these small details can make a huge difference on how your graphic
reads.
Label Axes
Along the same lines as explaining your encodings, you should always
label your axes. Without labels or an explanation, your axes are just there
for decoration. Label your axes so that readers know what scale points are
plotted on. Is it logarithmic, incremental, exponential, or per 100 flush-
ing toilets? Personally, I always assume it's that last one when I don't see
labels.
To demonstrate my point, rewind to a contest I held on FlowingData a
couple of years ago. I posted the image in Figure 1-12 and asked readers to
label the axes for maximum amusement.
FIGurE 1-12 Add your caption here.
There were about 60 different captions for the same graph; Figure 1-13
shows a few.
As you can see, even though everyone looked at the same graph, a simple
change in axis labels told a completely different story. Of course, this was
just for play. Now just imagine if your graph were meant to be taken seri-
ously. Without labels, your graph is meaningless.