Variance and Standard Deviation

The variance and the standard deviation are the most common and useful measures of variability. These two measures provide information about how the data vary about the mean.

If the data are clustered around the mean, then the variance and the standard deviation will be somehow small.

If, however, the data are widely scattered about the mean, the variance and the standard deviation will be somewhat large.

Learn more about variance and standard deviation by reading the explanation below.

Practice: Answer the following exercises about variance and standard deviation.