Everything I needed to know about econometrics, I learned from Arnold Kling
17th June 2008
Megan McArdle explains it all to you.
Correlations are, at best, suggestive. They are not by themselves evidence–nay, not even if you cross your arms, scowl at your opponent, and say “Well, then give me another explanation for this astonishing correlation!” Until you’ve got something better than a simple correlation, the burden of proof remains upon you.