Famous predictor Nate Silver explains why correlation doesn't necessarily imply causation.
Fill or Kill
HSBC Risk Index up to 2011 and Heat Maps showing correlations.
What are financial correlations?
Reasons for Correlations
Why do these arguably unrelated markets correlate?
Where there should be correlations, some they dont correlate..
Aussie - Gold a great delayed correlation trade from 12 to 600 hours apart!
How or Why was Italian stock market correlated to Copper? So how do you trade this..