Quote from bone:
ProfLogic:
If your meaning of "consistent" is the entire lifespan of your 15 years of correlation study, then I cede your point.
If your meaning of "consistent" is an annual refreshment of your correlation analyses, then I cede 75% of your point.
If your meaning of "consistent" includes fresher and higher frequency correlation analyses updates, then you are flat wrong.
I've had bankable correlations hold up for 3 years, 3 months, or only 3 weeks.
Case in point: three years ago, there was a very high intraday correlation between crude oil and the euro currency. (at that time crude was also very highly correlated with gold on an intraday basis) When that faded away to the point of statistical elimination, it was soon replaced by the Canadian dollar. When that faded away, the next (and current sweetheart) correlation was the Mexican Peso.
Is there a fundamental reasoning behind the statistical fitness? Sure - in the case of Gold, Euro, and Crude it was flight-to-quality in terms of capital flows. With the CD it was all about Canadian Oil Sands, and with the Peso it's all about PEMEX delivery into Cushing OK and the Gulf Coast refinery complex.
Some very good correlations cannot be explained by fundamentals and so I tend to shy away from them - RBOB Gasoline versus Copper being a case in point.
I could not possibly trade the market without correlations. And I have more consulting work than I can manage at the moment because of correlations.