چكيده به لاتين
Several factors affect customers' decisions regarding service selection. Two of the essential factors are the price and the service quality. The seller's credibility is also among the influential factors in selecting a service that is reinforced by advertising and service quality level. The emergence of the Internet has led to increasing attention by sellers to advertising through online group buying (OGB) platforms. Online group buying platforms (OGBPs) as a new form of e-commerce, offer a new channel for sellers to provide discounts on assorted services through promotion, and attract new customers with the opportunity to experience their services. This paper is conducted based on genuine issues observed in OGBPs where a seller decides to advertise its service by offering a discount coupon on an OGBP. Sellers aim to attract new customers by offering discounts on OGB platforms. Considering the cognitive uncertainty of parameters in a supply chain, all parameters of the problem are specified as fuzzy variables based on experts’ opinions. Accordingly, this paper develops a fuzzy mathematical model to simultaneously determine price, service quality, and advertising level in a dual channel supply chain during two current and future periods according to the centralized and decentralized models. The supply chain includes a seller, an OGB platform, and customers. The seller can sell the service through individual sales strategy (offline channel) or mixed sales strategy, selling its service through the OGB platform and offline channels. The demand function used in this study allows for the simultaneous examination of the three elements of price, service level, and advertising level on customer demand in an integrated manner. Initially, it is assumed that the competition between the seller and the platform is cooperative, and a centralized decision-making model is used. In addition, there is another game structure in the OGB market, which is called the decentralized decision model, in which the market is controlled by the platform called as OGBP-leader Stackelberg. Therefore, in this study, cooperative and non-cooperative behavior are examined. Also, in the following, three cooperative models and two non-cooperative models are developed for two competitive sellers in a dual group buying supply chain. By considering the structures of group buying platforms, different refunding policies and revenue sharing policies of unredeemed coupons are developed under different scenarios for the centralized and decentralized models. The optimal solutions of the problem are then defined using the game theory approach and fuzzy sets theory for each scenario. In addition, sensitivity analyses in this study also provide the effect of changes in essential parameters on the seller’s decisions to indicate the effectiveness of theoretical results of models and developing management insights. The problem studied in this research has various scientific applications, such as its application in cultural centers, recreation centers, health and beauty centers for determining prices, level of services, and advertisements.
