This document discusses measures of dispersion such as mean deviation. It provides formulas to calculate mean deviation from the mean, median, and mode. It also gives examples of calculating mean deviation from given data sets and interpreting the results. Mean deviation is the average of the absolute deviations from the mean, median, or mode. It indicates how far the values are spread out from the central tendency. The document shows how to compute mean deviation and its coefficient from sample data for different measures of central tendency.