In an increasingly data-driven world, it is more important than ever for students as well as professionals to better understand basic statistical concepts. 100 Questions (and Answers) About Statistics addresses the essential questions that students ask about statistics in a concise and accessible way. It is perfect for instructors, students, and practitioners as a supplement to more comprehensive materials, or as a desk reference with quick answers to the most frequently asked questions.

What Are Levels of Measurement, and Why Are They Important?

What Are Levels of Measurement, and Why Are They Important?

Levels of measurement (sometimes called scales of measurement) are the particular levels at which an outcome is assessed. There are four scales of measurement—nominal, ordinal, interval, and ratio—and each has its own set of characteristics.

Nominal levels of measurement are characterized by the categorical nature of the variable being measured. Variables such as political affiliation (party 1, party 2, or party 3), hair color (auburn, black, blond), and gender (male or female) are all categorical variables. This is the least precise level of measurement.

Ordinal levels of measurement are characterized by rank. Variables such as rank in class, order of finishing a race, and best-to-worst school project are ordinal in nature.

Interval levels of measurement are characterized ...