October 19, 2003
More Than One Way To Make A Venn Diagram

Joanne Jacobs reports that a high school in Kennewick, Washington has assigned students to compare the Salem Witch Trials, the internment of Japanese-Americans in World War II, the McCarthy era, and "the anti-terrorist fear since 9/11 which resulted in the establishment of Homeland security and the Patriot Act" as "instances where mass hysteria has ruined people's lives" (emphasis added). Students are instructed to created Venn diagrams to illustrate their work. No doubt the teacher is thinking of something like this, where objects A, B, and C all share the characteristics that would listed under ABC, and pairs of them share the characteristics AB, BC, and AC:

(I borrowed the illustration from the What is a Venn Diagram? page on the Electronic Journal of Combinatorics site, but copied it here so as not to hog their bandwidth. The first hit for "Venn Diagrams" on Google is http://www.venndiagrams.com, which sounds promising but seems to have been unplugged. Even the cached pages are missing a lot of pieces.)

Of course, this, too, is a Venn Diagram:

All it needs is a list of all the non-overlapping characteristics of contemporary Homeland Security with (e.g.) the Salem Witch Trials and Japanese-American internment. I wonder if any of the students will be clever enough to think of some approximation of the second illustration, and snarky enough to hand it in. Scratch that last part: of course high-school students are snarky enough. But will any of them be bold enough?

Post-script: It appears from Jacobs' quotation that the school doesn't think much of its students Venn proficiency, since they are asked to construct a separate diagram for each pair of events: A, B, and AB, but no C, AC, BC, or ABC. Perhaps I should redo the illustrations, but I'm too lazy.

Posted by Dr. Weevil at October 19, 2003 07:01 PM

this site doesn't provide anyone with an actual venn diagram with two circles. i think you should put that option on this site and then you will have more users.

Posted by: Alex Whalson on October 21, 2004 01:09 PM