Standard deviation (SD) is still the most widely used measure of dispersion, or in financial markets, risk.That all sounds a bit technical but it's actually pretty straightforward to understand. It is ...

About the author: Rick Lear is the founder and chief investment officer at Lear Investment Management. The idea of adding to or maintaining fixed-income exposure at a time of heightened market fear ...

In response to my article, Is the Stock Market Too Concentrated?, which relied upon standard-deviation calculations to assess investment risk, a reader wrote: “My problem [with your argument] is ...