Date of publication November 2011. Previous submissions of same underlying story from other sites:<p><a href="http://news.ycombinator.com/item?id=3237261" rel="nofollow">http://news.ycombinator.com/item?id=3237261</a><p><a href="http://news.ycombinator.com/item?id=2364425" rel="nofollow">http://news.ycombinator.com/item?id=2364425</a><p>These discussions are about a single, unreplicated observational study. The study doesn't prove causation and may not be generalizable to other countries besides the UK (where the study occurred).<p><a href="http://norvig.com/experiment-design.html" rel="nofollow">http://norvig.com/experiment-design.html</a>