Certified Rehabilitation Counselor Practice

Which measurement scale assigns numerals without distinguishing sizes or amounts?

1. Ordinal scale

2. Nominal scale

3. Interval scale

4. Ratio scale

The correct answer is: Nominal scale

The nominal scale is the correct choice because it categorizes data without implying any order or quantifiable difference between the categories. In this scale, numbers serve merely as labels or identifiers for distinct groups. For example, in a nominal scale, numbers might represent different types of fruit, such as 1 for apples, 2 for oranges, and 3 for bananas. The numbers have no mathematical significance; they simply indicate categories. Understanding the nature of the nominal scale distinguishes it from other measurement scales like the ordinal scale, which does indicate a rank order (e.g., 1st, 2nd, 3rd) but does not quantify the differences between those ranks. Interval and ratio scales, on the other hand, provide meaningful numerical values that allow for the comparison of magnitudes and include specific properties such as equal distances between values (interval) or a true zero point (ratio). Thus, the essence of the nominal scale lies in its role as a categorical classification without any inherent numerical hierarchy or distinction in size or amount.