# What is the variance of {12, 6, 7, 0, 3, -12}?

Feb 16, 2016

Population variance: $56.556$
Sample variance: $67.867$

#### Explanation:

To calculate the variance:

1. Calculate the arithmetic average (the mean)
2. For each data value square the difference between that data value and the mean
3. Calculate the sum of the squared differences

If your data represents the entire population:
4. Divide the sum of the squared differences by the number of data values to get the population variance

If your data represents only a sample taken from a larger population
4. Divide the sum of the squared differences by 1 less than the number of data values to get the sample variance