Ran across this on Twitter via the wonderful economist Noah Smith (@noahpinion, love that handle) of the statistical "work" of the "Spurious Correlations" web site (http://tylervigen.com/):
Source Spurious Correlations
People using random correlations to prove things is one of my pet peeves. The press does this a lot when a scientist in an announcement mentions a correlation as supporting evidence, and it gets translated in the article as "proof," but what's so much worse today is the tendency for pseudo-science to use outright false statements of causation based on data like this.
Worse still is the fad among climate-deniers to claim that the correlation between CO2 increases and global average temperatures is a "spurious correlation" and concluding that there's no proof of causation. Of course there's been endless experimental proof of the mechanisms on both micro and macro scales of the causation, but that fact is unfortunately often overlooked.
Where have you seen false correlation/causation examples?
The traveller must, of course, always be cautious of the overly broad generalisation. But I am an American, and a paucity of data does not stop me from making sweeping, vague, conceptual statements and, if necessary, following these statements up with troops.