A statistical method for measuring 'marginal utility' and testing the justice of a progressive income tax.
a statistˈikal mˈetod fˈor meazˈuriŋɡ mardʒˈinal ʊtilˈitɪ ˈand tˈɛstiŋɡ tˈe dʒˈustitʃe ˈof a proɡressˈive inkˈome tˈaks.