Somewhere back in your middle school and high school math classes, you no doubt learned about the mean and standard deviation as fairly fundamental concepts in arithmetic and statistics. You also knew ...

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How They Differ and Practical Uses in Finance and Investing Henry Hoenig has three decades of journalism experience as a news and economics editor in the U.S. and Asia, handling coverage of global ...

There are two formulae for standard deviation. \(s = \sqrt {\frac{{\sum {{{(X - \bar X)}^2}} }}{{n - 1}}}\) (where n is the sample size). The second formula is a re ...