# What is the difference between the formula for variance and sample variance?

Nov 5, 2015

Degrees of freedom of variance is $n$ but degrees of freedom of sample variance is $n - 1$

#### Explanation:

Note that

$\text{Variance} = \frac{1}{n} {\sum}_{i = 1}^{n} {\left({x}_{i} - \overline{x}\right)}^{2}$

Also note that

$\text{Sample Variance} = \frac{1}{n - 1} {\sum}_{i = 1}^{n} {\left({x}_{i} - \overline{x}\right)}^{2}$