Efficient cake-cutting

Efficient cake-cutting is a problem in economics and computer science. It involves a heterogeneous resource, such as a cake with different toppings or a land with different coverings, that is assumed to be divisible - it is possible to cut arbitrarily small pieces of it without destroying their value. The resource has to be divided among several partners who have different preferences over different parts of the cake, i.e., some people prefer the chocolate toppings, some prefer the cherries, some just want as large a piece as possible, etc. The allocation should be economically efficient. Several notions of efficiency have been studied:

  • The most common notion is Pareto-efficiency. It means that no other allocation is better for at least one participant and at least as good for everyone.
  • A weaker notion is non-wastefulness. An allocation is non-wasteful if no agent receives a piece of cake that is worth 0 for him/her, and worth more than 0 for another agent.

Most often, efficiency is studied in connection with fairness, and the goal is to find a division which satisfies both efficiency and fairness criteria.