The Dubins–Spanier theorems are several theorems in the theory of fair cake-cutting. They were published by Lester Dubins and Edwin Spanier in 1961. Although the original motivation for these theorems is fair division, they are in fact general theorems in measure theory.
There is a set , and a set which is a sigma-algebra of subsets of .
There are partners. Every partner has a personal value measure . This function determines how much each subset of is worth to that partner.