Std Deviation Equation. It is also known as root mean square deviation the symbol used to represent standard deviation is greek letter sigma σ 2. This estimator denoted by s n is known as the uncorrected sample standard deviation or sometimes the standard deviation of the sample considered as the entire population and is defined as follows.
Standard deviation is defined as the square root of the mean of a square of the deviation of all the values of a series derived from the arithmetic mean. Prior to the calculation of standard deviation in excel we need to calculate sum mean average value for the datasets. In the formula above μ the greek letter mu is the mean of all our values.
Square each deviation from the mean multiply.
The formula explained step 1. Next after calculating average mean you are required to perform the x x function. They are the individual x values. Where the sum value is calculated with the help of the sum formula i e.
