Measures of Variability

Measures of Variability or Spread

Measures of Variability also known as the measure of spread shows us the dispersion in the dataset and how the data is distributed around the center (Measure of Location) of the dataset. The most commonly used Measures of Variability are discussed below.

Variance

The Variance is the expected value (mean) of the squared differences of the data values from the mean. It shows us how close or far the values in a dataset are from the mean of the dataset in squared units.

Formula

$s^2={\frac{1}{n-1}\sum_{i=1}^n(x_i-\bar{x})^2}$

• $s^2$ is the variance.

• $n$ is the total number of values in the dataset

• $\sum_{i=1}^n$ is the sum of the values from 1 to n.

• $(x_i-\bar{x})^2$ is the square of the difference of each value in the dataset from the mean.

• $\sum_{i=1}^n(x_i-\bar{x})^2$ ...