http://1-formula.com/mathematical-formulas/standard-deviation-formula.html Read a most original, thorough analysis of standard deviation. Learn formula, algorithm, software to calculate standard deviation. en-us Sun, 21 Dec 2008 15:30:08 GMT Tue, 6 Jan 2009 19:10:47 GMT www.1-formula.com www.1-formula.com http://1-formula.com/mathematical-formulas/standard-deviation-formula/standard-deviation-formula2.html The standard deviation measures the spread of the data about the mean value. It is useful in comparing sets of data which may have the same mean but a different range. Tue, 6 Jan 2009 19:10:47 GMT http://1-formula.com/mathematical-formulas/standard-deviation-formula/standard-deviation-formula2.html