Local advertising externalities and cooperation in one manufacturer-two retailers channel with exogenous marginal profits

Game theory is a relevant and powerful tool for analyzing strategic interactions in a supply chain in which the decision of each player affect the payoff of other players. In order to relax the classical two supply chain members’ situation to a three supply chain members’ situation and to integrate the problem of competition at retail level, we consider a supply chain consisting of a monopolistic manufacturer and two duopolistic retailers. The latter two are geographically related. Our paper examines the optimal decisions on advertising (local, national and cooperative advertising) in a centralized and a decentralized supply chain using Stackelberg – Cournot game, Stackelberg - Collusion game and Cooperative games, and we investigate the impact of the existing of competition at retail level, the retailer coalition and the cooperation between all supply chain members’ on the channel members’ optimal decisions, on the sales volume and on the profits. Applying the equilibrium analysis and using numerical example, comparing results indicates that all advertising, the sales volume of each member and the total profit in the centralized decision-making are larger than those in the decentralized decision-making. Retailer coalition harms themselves (in terms of profit) despite the increasing of sales, but is beneficial to the manufacturer. We identify also the feasible solutions of the best cooperative advertising scheme that members are interesting in cooperation.