ABSTRACT
Researchers, reporters, administrators, and citizens should understand measurement, i.e., how numbers, words or other descriptors are assigned to broader concepts, behaviors, or phenomena. This is true whether data represent environmental conditions, the state of the economy, achievement, public opinion, or something else. Data can influence policy decisions, demonstrate accountability, and classify people. Understanding measurement quality allows us to assess if data are appropriately comparing different cities or counties on a characteristic, such as poverty, or a standard, such as air quality. Consequently, researchers must take care in designing measures, and data users must understand measurement concepts.
