(This article was originally published at Effective Graphs, and syndicated at StatsBlogs.)
Thanks to Jason Oberholtzer (@ilovecharts) for tweeting about the following graph from the Boston Metro. His tweet just said, “Ugly polls.”
Figure 1. Source: http://ilovecharts.tumblr.com/post/33308788744/from-the-boston-metro-oct-10th-hannabeth-well
How many problems do you see with this figure?
As a starter, donut charts do not communicate very well. However, that is minor next to the fact that the segments of a donut must add to 100%. This is clearly the wrong chart for the data. If that’s not enough, it is not drawn to scale. I don’t trust my eyes to judge this since I know that dark colors appear smaller than lighter colors. Therefore, to check my assertion, take out your rulers and measure.
Here is the same data in a simple bar chart. The default in Microsoft Excel did not use a zero baseline for the bars so I needed to edit the figure.
Figure 2. The data from Figure 1 is redrawn more accurately.
Let’s demand more from our news sources.
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