A utility function that can be subjected to a positive affine transformation without altering the implied preference order. A positive affine transformation applied to the initial utility function U generates the transformed utility function U* = a + bU, where b > 0. The utility function U is cardinal if the functions U and U* represent the same set of underlying preferences. An example of cardinal utility is an expected utility function.
|Reference: Oxford Press Dictonary of Economics, 5th edt.|