# How to Calculate Sigma?

Learn how to calculate Standard Deviation / Sigma (Ïƒ).

## Standard Deviation Calculation

Standard Deviation in mathematics is a measure of how much the data of a group differ from the mean value for the group. It is expressed as SD, or Greek letter sigma Ïƒ. Hence, standard deviation is also termed as sigma.
Let us learn here how to calculate sigma Ïƒ for a set of data with a simple example. Formula Used:  Step 1: Let us consider a data set : 6, 1, 4, 3, 10, 8 Step 2: Find the mean of the data set,
6+1+4+3+10+8 / 6 = 32 / 6 = 5.333 Step 3: Subtract the mean from each individual value and square the result.
(6 - 5.333)2 = (0.667)2 = 0.444889
(1 - 5.333)2 = (-4.333)2 = 18.774
(4 - 5.333)2 = (-1.333)2 = 1.776889
(3 - 5.333)2 = (-2.333)2 = 5.442889
(10 - 5.333)2 = (4.667)2 = 21.780889
(8 - 5.333)2 = (2.667)2 = 7.112889 Step 4: Find the mean of the above squared differences.
0.444889 + 18.774 + 1.776889 + 5.442889 + 21.780889 + 7.112889 / 6 = 55.332445 / 6 = 9.222 Step 5: Find the square root of the above result to get sigma Ïƒ value,
2âˆš9.222 = 3.036
sigma Ïƒ = 3.036 