To finish off the loose theme of data visualization that has been around in the last few posts, here is a great story of the misuse of graphics.
Recently the Romney presidential campaign team put out a series of Venn diagrams, which they called infographics, about President Obama’s promise and gaps (see left). Unfortunately, these are not Venn diagrams in the truest sense. Venn diagrams are designed to show all possible combinations between a finite collection of sets. Venn diagrams normally comprise overlapping circles, where the interior of the circle symbolically represents the elements of the set, while the exterior represents elements that are not members of the set, and the intersection of these circles are elements which belong to all sets, beautifully illustrated below (or here for mythical creatures).
The Romney campaigns inability to make a Venn diagram has become a source of Venn diagrams by various Venn-savvy bloggers. Upworthy has created a Mitt, Venn and Now tumblr with some great Venns, below is a nice sampling.
My favorite is the one below, which proves that when used properly Venn diagrams can be very effective in clearly presenting information about a candidate.