Retailers’ coalition and quantity discounts under demand uncertainty

Coalition of retailers is a nowadays phenomenon in retailing channels (RCs) that makes it possible for the retailers to enhance their business performance and respond to the consumers' needs more effectively. This paper discusses the retailers' coalition advantages and challenges in a two-echelon retailing channel consist of one wholesaler and two non-competing retailers who serve the consumers. The model is developed under a classic newsvendor problem where an all-unit quantity discount is offered by the wholesaler. Our investigations are conducted for both homogeneous/heterogeneous retailers under three different scenarios. In the developed models, the retailers start to make a coalition and make a joint order in order to gain more from the offered discount by the wholesaler, and then using a heuristic procedure they allocate the received order to serve their individual markets. The main objective of this study is to analyze and resolve challenges of the retailers' coalition when a quantity discount is offered in order to make them capable to meet consumers' needs in the best possible manner. Three models are developed: (1) no-coalition decentralized scheme, (2) decentralized coalition where the retailers coalesce, and (3) centralized coalition where not only the retailers but the wholesaler participate in the coalition scheme. Our paper contributes to the RC management literature by analyzing the benefits of the retail coalition in taking most advantage from an offered quantity discount. Results demonstrate that the optimal configuration of the retailers' coalition increases profits of both the retailers and the RC in comparison with the no-coalition scenario. Our findings help procurement managers to rethink their ordering policy toward forming coalition to gain more profits and enhance their service level to meet consumers’ needs.