복수의 공급업체가 경쟁하는 공급사슬의 최적가격정책

Abstract

본 연구는 임의의 공급사슬에서 서로 경쟁하는 복수의 공급업체와 하나의 소매업체가 존재하는 경우에 해당 공급사슬 전체가 달성하는 이익을 최대화할 수 있는 거래가격과 그 가격의 결정과정을 분석하였다. 보다 구체적으로 경쟁 공급업체의납품가격이 주어진 상황에서 특정 공급업체는 자신이 속한 공급사슬의 이익을 최대화하기 위해 최적의 납품가격을 어떻게결정하여야 하며 그 가격의 특성은 어떠한지를 살펴보았다. 결과적으로 경쟁하는 두 공급업체 중 일방이 납품가격을 조정하게 되면, 상대 공급업체는 이익의 감소가 발생하게 되므로 이를 방지하기 위하여 동일한 방향으로 납품가격을 조정하게됨을 증명하였다. 그리고 위와 같은 역학적 구조가 반복되어 납품가격이 균형에 이르게 되는 과정에서 소매업체도 소매가격을 조정하게 됨을 논증하였다. 이 때 공급사슬 전체의 이익은 두 공급업체가 각각의 납품가격을 자사 제품에 대한 취득 또는 생산원가수준으로 조정하면 최대화될 수 있다는 것을 밝혀내었다. 이러한 과정은 결국 최적소매가격의 하락으로 귀결되어, 최종소비자를 포함하여 거래에 참가하는 모든 당사자의 효용을 조정 전보다 향상시킬 수 있게 된다.

We analyze an optimal pricing scheme of a product and its inherent dynamics to maximize the profit for the entire supply chain with two competing suppliers and a monopolistic retailer when the demand pattern is uncertain and the back-order is allowed in case. In this environment we assume that the products by the suppliers are substitutable each other with a certain degree even though their retail prices could be different each other in the market depending on the retailor's decision. It is proved that each player in the supply chain is able to achieve increased profit comparing with the present one by following the suggested pricing scheme with some game theoretical process. In addition we show that the model appears to show equivalent results with the independent demand case if there is no substitutability between two products in our model. Under the circumstance the suggested pricing scheme for the products become mutually exclusive, which is consistent with many well-known results in the past researches. Also we show that the new retail price as well as the whole prices are quite sensitive to various market related parameters such as production costs by the suppliers and the relative size of each product's retail market. From the standpoint of suppliers, the new pricing scheme suggests that each supplier in the supply chain should determine its wholesale price considering several relevant factors of the scheme to maximize the joint profit with its retailer when the competitor maintains a certain level of its wholesale price. On the other hand, the competitor is supposed to suffer a significant deal of loss in its demand and profit if it sticks to its existing wholesale price when the competing supplier changes its wholesale price following the scheme we suggested. Therefore the process to determine the wholesale prices are supposed to follow an game theoretical procedure considering the competing rival's pricing policy. If a supplier deviates the scheme and apply some different wholesale price, it has to swallow a bitter pill. The magnitude of such an impact tends to depend on the degree of substitutability between two products as well as some other market related parameters such as the production costs of both sides and the price elasticity of the two products. As a result the scheme evokes a strong incentive for the competitor to participate in the cooperative pricing policy with its retailor to avoid such an embarrassing situation. If both suppliers join in the suggested pricing scheme in this research, then all players including the retailer are able to enjoy a certain degree of increased profit creating more demand in the market with the lower retailor prices. Therefore the suggested pricing scheme is beneficial even to the retail customers. More specifically, this reciprocal relation between two suppliers is continued until it reaches a certain equilibrium in terms of their wholesale pricing. That relation is extended to the retailer so that it changes its retail price so as to maximize its profit based on the new wholesale prices set by the two competing suppliers. Finally we prove that the profit achieved by the entire supply chain applying the suggested pricing scheme is maximized when the suppliers offer their competing products to its retailor with the prices equivalent to their production costs without adding any supplier's margins. In such a case the suppliers are encouraged to take a part of the increased profit through the supply chain by adopting a new profit sharing program such as a revenue sharing transaction model or so-called a franchise transaction model to make the transactions feasible. With these kind of sharing programs, the suppliers are guaranteed to achieve the profits which are at least as large as the previous ones. Furthermore under the new pricing scheme, even the retail price tends to be lower than the previous one so that it is beneficial to the retail customers in the market eventually.