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A shark attack on a chart

Happy New Year!

Starting 2011 with shark attacks courtesy of Julien D.


Sharkattack It seems like the good chart did not survive a shark attack if one were to judge from what's left of it.

It's a distorted pie chart with some kind of 3D hemispherical add-on, or it's a cross-sectional chart with the top of a sphere lopped off.

Charts of the USA Today variety do not usually feature here but this one has the aspiration to inform readers -- the chart appears on a web page that purports to correct some myths about shark attacks.

The biggest casualty of the shark attack is the ordering of the data labels. It is a brain teaser as to what criterion was used to order the pie slices: it's not the total number of accidents, nor the number of deaths, nor the death rate, nor alphabetical.

It's also unclear why the data labels were made vertical. The palette of colors is, however, typical of pie charts.

Since a death rate is usually defined as deaths / total accidents, not the other way round, even the numerical data labels is harder to read than necessary.


There are two primary questions this chart is intended to address: the prevalence of different types of shark attacks, and the death rate of each type of attack (as a proportion of reported accidents).

We try a scatter plot showing these two metrics, adding notes to point out where the interesting data is.