Cost allocation studies on the rational allocation method for the common cost of the joint products or services that provide different benefits to each economic entity under the constraints of the efficiency and fairness. Cooperative game theory is often used for cost allocation and studies on a fair and efficient allocation of the utility if some feasible utility for a whole or subset of the players in a game is given. This study shows a variety of cooperative game theory approaches and discusses the pros and cons of each approach.

If the coalition of players orders the product together, then they can reduce the inventory costs such as ordering cost and holding cost. Inventory game can be defined as the allocation of the inventory costs to the players in a fair and rational manner. The characteristics recommended for the solutions provided by the method for the inventory game are completeness, rationality, and marginality. The solutions that satisfy these characteristics are in the core, where the proportional method may depend on the allocator. This study has found out that the solutions of the proportional method with some allocators for economic order quantity model exist in the core.