Supply chain collaboration

In the past, research in operations management focused on single-firm analysis. Its goal was to provide managers in practice with suitable tools to improve the performance of their firm by calculating optimal inventory quantities, among others. Nowadays, business decisions are dominated by the globalization of markets and increased competition among firms. Further, more and more products reach the customer through supply chains that are composed of independent firms. Following these trends, research in operations management has shifted its focus from single-firm analysis to multi-firm analysis, in particular to improving the efficiency and performance of supply chains under decentralized control. The main characteristics of such chains are that the firms in the chain are independent actors who try to optimize their individual objectives, and that the decisions taken by a firm do also affect the performance of the other parties in the supply chain. These interactions among firms’ decisions ask for alignment and coordination of actions. Therefore, game theory, the study of situations of cooperation or conflict among heterogenous actors, is very well suited to deal with these interactions. This has been recognized by researchers in the field, since there are an ever increasing number of papers that applies tools, methods and models from game theory to supply chain problems

p-additive games: a class of totally balanced games arising from inventory situations with temporary discounts

We introduce a new class of totally balanced cooperative TU games, namely p -additive games. It is inspired by the class of inventory games that arises from inventory situations with temporary discounts (Toledo, 2002) and contains the class of inventory cost games (Meca et al. 2003). It is shown that every p-additive game and its corresponding subgames have a nonempty core. We also focus on studying the character concave or convex and monotone of p-additive games. In addition, the modified SOC-rule is proposed as a solution for p-additive games. This solution is suitable for p-additive games since it is a core-allocation which can be reached through a population monotonic allocation scheme. Moreover, two characterizations of the modified SOC-rule are provided

Production-inventory games and pmas games: characterizations of the Owen point

Production-inventory games were introduced in Guardiola et al. (2007) as a new class of totally balanced combinatorial optimization games. From among all core-allocations, the Owen point was proposed as a specifically appealing solution. In this paper we study some relationships of the class of production-inventory games and other classes of new and known games. In addition, we propose three axiomatic characterizations of the Owen point. We use eight axioms for these characterizations, among those, inessentiality and additivity of players' demands are used for the first time in this paper

Cooperation and profit allocation in distribution chains

We study the coordination of actions and the allocation of profit in supply chains under decentralized control in which a single supplier supplies several retailers with goods for replenishment of stocks. The goal of the supplier and the retailers is to maximize their individual profits. Since the outcome under decentralized control is inefficient, cooperation among firms by means of coordination of actions may improve the individual profits. Cooperation is studied by means of cooperative game theory. Among others we show that the corresponding games are balanced and we propose a stable solution concept for these games

Profit allocation in agricultural supply chains: exploring the nexus of cooperation and compensation

In this paper, we focus on decentralized agricultural supply chains consisting of multiple non-competing distributors satisfying the demand of their respective markets. These distributors source a single product from a farmer through an agricultural cooperative, operating in a single period. The agents have the ability to coordinate their actions to maximize their profits, and we use cooperative game theory to analyze cooperation among them. The distributors can engage in joint ordering, increasing their order size, which leads to a decrease in the price per kilogram. Additionally, distributors have the opportunity to cooperate with the farmer, securing a reduced price per kilogram at the cost price, while compensating the farmer for any kilograms not acquired in the cooperation agreement. We introduce multidistributor-farmer games and we prove that all the agents have incentives to cooperate. We demonstrate the existence of stable allocations, where no subgroup of agents can be better off by separating. Moreover, we propose and characterize a distribution of the total profit that justly compensates the contribution of the farmer in any group of distributors. Finally, we explore the conditions under which the farmer can be compensated in order to maximize their revenues when cooperating with all players

p-additive games: a class of totally balanced games arising from inventory situations with temporary discounts

We introduce a new class of totally balanced cooperative TU games, namely p-additive games. It is inspired by the class of inventory games that arises from inventory situations with temporary discounts (Toledo Ph.D. thesis, Universidad Miguel Hernández de Elche, 2002) and contains the class of inventory cost games (Meca et al. Math. Methods Oper. Res. 57:481–493, 2003). It is shown that every p-additive game and its corresponding subgames have a nonempty core. We also focus on studying the character of concave or convex and monotone p-additive games. In addition, the modified SOC-rule is proposed as a solution for p-additive games. This solution is suitable for p-additive games, since it is a core-allocation which can be reached through a population monotonic allocation scheme. Moreover, two characterizations of the modified SOC-rule are provided.This work was partially supported by the Spanish Ministry of Education and Science and Generalitat Valenciana (grants MTM2005-09184-C02-02, ACOMP06/040, CSD2006-00032)

Unitary Owen Points in Cooperative Lot-Sizing Models with Backlogging

This paper analyzes cost sharing in uncapacitated lot-sizing models with backlogging and heterogeneous costs. It is assumed that several firms participate in a consortium aiming at satisfying their demand over the planning horizon with minimal operating cost. Each individual firm has its own ordering channel and holding technology, but cooperation with other firms consists in sharing that information. Therefore, the firms that cooperate can use the best ordering channels and holding technology among members of the consortium. This mode of cooperation is stable. in that allocations of the overall operating cost exist, so that no group of agents benefit from leaving the consortium. Our contribution in the current paper is to present a new family of cost sharing allocations with good properties for enforcing cooperation: the unitary Owen points. Necessary and sufficient conditions are provided for the unitary Owen points to belong to the core of the cooperative game. In addition, we provide empirical evidence, through simulation, showing that, in randomly-generated situations, the above condition is fulfilled in 99% of the cases. Additionally, a relationship between lot-sizing games and a certain family of production-inventory games, through Owen’s points of the latter, is described. This interesting relationship enables easily constructing a variety of coalitionally stable allocations for cooperative lot-sizing models.The research authors is supported from Spain’s Ministerio de Ciencia, Innovación y Universidades (MCIU), from the Agencia Estatal de Investigación (AEI) and from the Fondo Europeo de Desarrollo Regional (FEDER) under the projects MTM2016-74983-C02-01 and PGC2018-097965-B-I00. The research of the third author is also partially supported from projects FEDER-US-1256951, CEI-3-FQM331 and NetmeetData: Ayudas Fundación BBVA a equipos de investigación científica 2019

Allocating the surplus induced by cooperation in distribution chains with multiple suppliers and retailers

The coordination of actions and the allocation of profit in supply chains under decentralized control plays an important role in improving the profits of retailers and suppliers in the supply chain. We focus on supply chains under decentralized control in which noncompeting retailers can order from multiple suppliers to replenish their stocks. The goal of the firms in the chain is to maximize their individual profits. As the outcome under decentralized control is inefficient, coordination of actions between cooperating agents can improve individual profits. Cooperative game theory is used to analyze cooperation between agents. We introduce multi-retailer-supplier games and show that agents can always achieve an optimal profit by cooperating and forming the grand coalition. Moreover, we show that there will always be stable allocations of total profit among the firms which cannot be improved by any coalition. In addition, we propose and characterize a stable allocation of the total surplus induced by cooperation.We gratefully acknowledge financial support from the Ministerio de Ciencia, Spain, Innovación y Universidades (MCIU/AEI/FEDER, UE) through project PGC2018-097965-B-I00, PID2020-114594GB–{C21,C22}, PID2022-137211NB-100; and Fundación BBVA: project NetmeetData (Ayudas Fundación BBVA a equipos de investigación científica 2019), Spain; and by Generalitat Valenciana, Spain through project PROMETEO/2021/063

Production-Inventory games: a new class of totally balanced combinatorial optimization games

In this paper we introduce a new class of cooperative games that arise from production-inventory problems. Several agents have to cover their demand over a finite time horizon and shortages are allowed. Each agent has its own unit production, inventory-holding and backlogging cost. Cooperation among agents is given by sharing production processes and warehouse facilities: agents in a coalition produce with \ the cheapest production cost and store with the cheapest inventory cost. We prove that the resulting cooperative game is totally balanced and the Owen set reduces to a singleton: the Owen point. Based on this type of allocation we find a population monotonic allocation scheme for this class of games. Finally, we point out the relationship of the Owen point with other well-known allocation rules such as the nucleolus and the Shapley value