Final answer:
Demographic questions like gender, education, and ethnicity are categorized using nominal scales, which are used to label data without implying any order or numeric value.
Step-by-step explanation:
Many demographic questions, such as gender, education, and ethnicity are examples of nominal scales. A nominal scale is a level of measurement used to categorize data without a numeric value or order. Gender, ethnicity, and various demographic attributes are typically labeled without a hierarchical ranking or score, staying true to the nominal scale definition. Unlike ordinal, interval, or ratio scales, nominal scale data are not ordered, and no arithmetic comparison between data points is possible. For example, classifying people by their ethnicity, such as Asian, Hispanic, African American, or Caucasian, is nominal since no order or ranking is implied.