Something to look over with students: Recent article on bad statistics
The case echoes a similar statistical legend — the belief that to be healthy we should drink eight glasses of water a day. Last week, researchers at the University of Pennsylvania decided to search for the source of this statistic. Their conclusion: “It is unclear where this recommendation came from.” In other words, they could not find any study to support the “eight glasses” claim.
See this and other fun non-facts at the link.