Standard deviation is a metric that shows the variability of a security’s returns over time. It can be used to gauge volatility based on past performance and compare a future return to past returns.

Rate of return and standard deviation are two of the most useful statistical concepts in business. These two figures will tell you whether a business project is worth the investment and trouble, given ...

Usually when it comes to writing, mathematics and statistics probably aren’t the first things that come to mind. However, quite the number of us have had to face an instance where a source based on ...

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 ...