In statistics, the average amount a number varies from the average number in a series of numbers. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.

When working with a quantitative data set, one of the first things we want to know is what the "typical" element of the set looks like, or where the middle of the set is. We do this by finding a mean ...

Ryan Eichler holds a B.S.B.A with a concentration in Finance from Boston University. He has held positions in, and has deep experience with, expense auditing, personal finance, real estate, as well as ...

Caroline Banton has 6+ years of experience as a writer of business and finance articles. She also writes biographies for Story Terrace. Chip Stapleton is a Series 7 and Series 66 license holder, CFA ...

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 ...