Question

What is the difference between variance and variability?

Answer 1

To know the difference between variance and variability firstly we will write their definition. As we know that variance is the expectation of a random variable from its mean of the squared deviation. Variability is the extent to which the data points vary from the average value in a data set or statistical distribution.

Complete step-by-step answer:
Both of the terms given are used in the statistical distribution data.
Variance is the average of the squared deviation from its mean of a random variable. Its formula is given as below:
For Variance of random variable $X$ we use given formula:
$Var\left( X \right)=E\left[ {{\left( X-\mu \right)}^{2}} \right]$
Variability is used for the inconsistency of a data set; it measures how much the data varies in a data set.
We can say that Variance, standard deviation and InterQuartile range of a data set are all measures of Variability.
Hence the difference between Variance and Variability is that Variance is a measure of Variability.

Note: Variability is an extent to which a data set can vary from the average value and also an extent to which a data point differs from each other. It is commonly used in financial and statistical sectors. A distribution with the same mean can have different amounts of variability. Variance is used to measure how spread out the data points are from their average value. Variance ideas are used in many statistics topics such as in descriptive statistics, hypothesis testing and in many more topics.