Monday, September 12, 2016

Maybe This Information is Beautiful, It's Just Not Accurate

This is an image from the e-book Information is Beautiful from the site of the same name. But they've made the same mistake that has long served to help people learn How to Lie with Statistics by Darrell Huff.  The graphic below, from Huff's book, shows the comparison of bags of money representing an average weekly wages from two countries. The one on the right earning twice as much as the one on the left. Showing how to lie, the bags are drawn so that the on the right is twice as tall as the one on the left, but this doesn't give us the correct visual image, since the graphic artist has doubled both the height and the width to produce the image on the right. The resulting visual impression is that the bag on the right is four times the one on the right. A perfect image to mislead.

Now the graphic from Information is Beautiful purports to represent the percentage of children in poverty. On the left is shown a small shadow silhouette of a young child with arms raised that represents 2%, the percentage of children in poverty in Denmark. Compare this with the larger silhouette for Germany representing 10%. Even in this flat 2-d outline more than 5 of the Denmark outlines could fit in the Germany outline.  The problem, of course, is that a graphic artist has lied again and doubled both the height and width of the silhouettes to represent these numbers. This distorts any comparisons that could be made with these data. And it gets worse, since we are to understand these are images of 3-dimensional children!

I recall decades ago this, now classic graphic, when it appeared in the Washington Post. The same mistake of displaying data using the same error with the same methods (compare the Eisenhower dollar with the Carter dollar). You would think....


gasstationwithoutpumps said...

The money-bag illustration is worse than you say: because it looks like a 3D picture, the visual impression is of 8× not just 4×.

Robert W. Jernigan said...

Yes, you are right, as is mentioned in Huff's book.