Which of the following is NOT one of the five common measures of dispersion?

The correct answer is the mean because it is a measure of central tendency, not a measure of dispersion. Measures of dispersion are used to describe the variability or spread of a dataset, indicating how much the data points differ from each other and from the center of the distribution.

Standard deviation quantifies the amount of variation or dispersion in a set of values, where a low standard deviation indicates that the values tend to be closer to the mean, while a high standard deviation indicates that the values are spread out over a wider range. The range, simply the difference between the highest and lowest values in a dataset, provides a basic measure of variability. Percentiles categorize data points into relative standing within the dataset, indicating the value below which a certain percentage of observations fall, which also reflects dispersion.

Understanding these distinctions highlights that while the mean provides insight into the central value of a dataset, it does not indicate how spread out the data is. Therefore, the mean does not fit into the category of measures of dispersion.