Introductory statistics textbooks rarely discuss the concept of variability for a categorical variable and thus, in this case, do not provide a measure of variability. The impression is thus given that there is no measurement of variability for a categorical variable. A measure of variability depends on the concept of variability. Research has shown that "unalikeability" is a more natural concept than "variation about the mean" for many students. A "coefficient of unalikeablity" can be used to measure this type of variability. Variability in categorical data is different from variability in quantitative data. This paper develops the coefficient of unalikeability as a measure of categorical variability.
- Prof Dev