Weekend cross-posting

On the book blog this past week, I discussed Steven Strogatz's column "Chances Are" in the New York Times. Professor Strogatz has been hired as a columnist to write about mathematical topics, and his most recent column concerns Bayes' Theorem, and its use in analyzing screening tests. In addition, a reader was curious about the (over-)reaction of  officials in Boston who advised residents to stop drinking tap water for fear of possible contamination which has not been verified.