Learn why correlation—not allocation—is the key to diversification, and how ETFs can help build portfolios with assets that truly move differently.

The one-year correlation between the S&P Equal Weight Index and S&P 500 has dropped to a record low of 79%, revealing extreme ...

Adam Hayes, Ph.D., CFA, is a financial writer with 15+ years Wall Street experience as a derivatives trader. Besides his extensive derivative trading expertise, Adam is an expert in economics and ...

In general, stock correlation refers to how stocks move in relation to one another. While we can speak generally about asset classes being positively or negatively correlated, we can also specifically ...

Almost every day you can find in media commentary that XYZ is causing stocks to fall (or rise). Such definitive statements are common—but what’s almost always missing is statistical proof. And if you ...

In the first case, there is a strong upward-sloping relationship between X and Y; in the second case, no apparent relationship; in the third case, a strong downward-sloping relationship. Note the ...

Correlation doesn't imply causation. You've probably heard that before. It's a true statement that's important in statistical analysis—if more tall people own cats, that doesn't mean that cats cause ...

Depressed people send more email. They spend more time on Gchat. Researchers at the Missouri University of Science and Technology recently assessed some college students for signs of melancholia then ...