On alternative pizzas, pie charts and datavis pedantry

So our usually calm data visualization corner on Twitter was shaken by this tweet:

quickly followed by this one:

What was all the fuss about? Well, Elijah Meeks summarizes it nicely:

So, was this much ado about nothing? I don’t think so.

Putting a few percentages near all things circular is a dangerous thing to do on social media. It invites scrutiny by the pie-charts-are-bad mob, so do it at your own peril. The fine line between humor and trollish behavior is often blurred. If it is round like a pie chart, percentages are displayed as in a pie chart, has slices as a pie chart, then it can only be a pie chart. So let’s have some fun!

People tend to follow the path of least effort. That means using  defaults and following the rules. There is nothing wrong with defaults and rules, but some are stupid, and some need context to be understood. I’m often worried that “no pies” is the only part of the message heard beyond the choir.

Now, I don’t have the time to check all the replays to the original tweet, but I couldn’t find a mention to the elephant in the room. If you look closely, there is a note below that says, among other things, “Other items not depicted include: onions (62%), chicken (56%)….”. So, because @yougov couldn’t find a stock photo depicting onions and chicken these very large items where relegated to a footnote.

This is the real issue: molding the data to fit your clever (?) design, and it happens too often. This pizza-not-pie incident is just silly and light. But think about it a bit: replace “molding the data” with “alternative facts” and “design” with “ideology” and things suddenly become very serious. There are some red lines, don’t let l’air du temps blur them too.