# Measures of Variability

A measure of central tendency which represents the centralness of a data set is not sufficient to describe the data distribution completely. If it is observed the means of two data distributions are equal, it cannot be concluded that the individual values in the two distributions are distributed in a similar way. In one distribution most of the values might be found clustered around the mean and in another, the data values might be spread over a greater range of values. Thus we need a measure that will convey the spread of the data set to understand the distribution better. Such measures are called the measures of variability.