It is important to know the central value of a distribution, but it is just one characteristic of the distribution. Measures of dispersion indicate how narrow or how spread out the values are around the central value. The dispersion of nominal level data is typically best analyzed with the range. The range or average absolute deviations from the median can be used with ordinal level data. Interval and ratio data can be examined with the variance or standard deviation. You responses should focus on range, standard deviation and variance.

Question:

What is meant by measures of dispersion? What are they and in what type of variables are they appropriate? Why should measures of dispersion be presented along with measures of central tendency? Provide applicable examples of this, to include websites.