When comparing economic well-being using income or expenditures, an equivalence scale is often used to adjust for differences in characteristics that affect needs. For example, a family of two is assumed to need more income than a single person, but not twice as much due to the economies of...

Equivalence scales are often used to adjust household income for differences in characteristics that affect needs. For example, a family of two is assumed to need more income than a single person, but not double due to economies of scale in consumption. However, in comparing economic well-being...