Types of measurement in Metrics:
A) Nominal: a nominal scale assigns items to a category. For example, the category may be a simple "yes" or "no." In the case of a family, a nominal scale assigns items to categories like grandfather, grandmother, father, mother, son or daughter. In the case of an automobile, categories could be small sedan, midsize sedan, large sedan, SUV, etc.
B) Ordinal: an ordinal scale identifies items in order of magnitude. For example, a customer survey might ask for ratings of service on a scale of 1 through 5, where 5 is best. That means a score of 4 is better than a score of 2. But it does not mean that a 4 is twice as good as a 2, or that a 4 is four times as good as a 1.
C) Cardinal: a cardinal scale is also known as a ratio scale. For example, the numbers 1, 2, 3, ... represent a cardinal scale. For a ratio scale, 12 is four times 3, and two times 6.