هماهنگی زنجیره تامین از طریق قراردادهای ناشی از تخفیف

In this paper three different types of rebate induced contract namely direct-rebate and revenue sharing contract; downward direct rebate contract; direct-rebate and effort sharing contract are proposed for supply chain coordination perspective. Effectiveness and flexibility of proposed contracts under linear and iso-elastic demand are discussed analytically. It is shown that under certain conditions both manufacturer and retailer can gain more profit by means of appropriate coordination contracts. Several important implications are derived analytically to point out relationship among characteristically different contracts. Results are illustrated with numerical examples.

A growing body of literature on operations management has suggested that a high degree of supply chain integration is needed in order to optimize the performance of chain. In this paper, three different rebate and effort induced contracts, like mixing of push–pull strategies are proposed to coordinate the supply chain where the manufacturer is the Stackelberg leader. The proposed coordination policies are based on the combination of “retailer rebate” and “customer rebate”. These two forms of rebate are characteristically different as retailer rebate enlarges the retailer’s margin on every unit sold, whereas consumer rebate enhances the demand for the product. The marketing and economics literature have investigated the use of customer rebates as well as retailer rebate. Gerstner and Hess (1995) have examined how retailer and consumer rebate induce the retailer and how such promotions influence manufacturer and channel profits. Taylor (2002) has considered retailer rebates in a model where demand is stochastic, but the retail price is exogenously given. The author has demonstrated that the sales rebate contract that does not coordinate on its own, can coordinate the channel if it is combined with buy back contract. Krishnan et al. (2004) have focused on the use of retailer rebates in the presence of retailer efforts. Bruce et al. (2006) have analyzed trade promotions and cash rebates by explicitly incorporating a durability measure for the manufacturer’s products. Chen et al. (2007) have claimed that rebates always benefit the manufacturer unless all of the buyers redeem their rebates. Aydin and Porteus (2009) have compared a per-unit retailer rebate and a per-unit customer rebate. The authors have concluded that neither the manufacturer nor the retailer always prefers one particular rebate to the other. Demirag et al. (2010) have analyzed customer rebate and retailer incentive promotions in the auto industry. (Yang et al., 2010) have shown that rebate promotions, combined with manufacturer’s suggested retail pricing, can dampen price-setting retailers’ possible adverse response to the promotion. Although rebate increases sales, revenues and market share; operation managers suggest that a high degree of coordination is essential for the improvement of overall supply chain performance. Coordination of supply chain is imperative for improving its performance. By applying contractual relationships among members of a supply chain double marginalization can be eliminated. As a result optimal output of a supply chain can be obtained. Mainly, buybacks (Lee and Rhee, 2007 and Xiao et al., 2010); mail-in-rebate (Chen et al., 2007) quantity discount (Weng, 1995, Cachon, 2003 and Hsieh et al., 2010); Revenue sharing (Cachon and Lariviere, 2005 and Gerchak et al., 2006); two part tariffs (Lariviere, 1999); quantity flexibility contracts (Tsay, 1999); target-level sales rebates (Taylor, 2002) and so forth have been studied as tools for supply chain coordination. There are rich literatures on supply chain coordination with revenue-sharing and whole sale price discount contracts. Gerchak and Wang (2004) have investigated two very distinct types of arrangements between a retailer and its suppliers. They have explored the resultant equilibrium in components delivery quantities in the decentralized supply chain, and its implications for participants and systems expected profits. Cachon and Lariviere (2005) have found that revenue-sharing is equivalent to buy-backs in the news-vendor case and concluded that revenue-sharing well coordinates a supply chain with retailers competing in terms of sales volumes. Veen and Venugopal (2005) have illustrated that revenue-sharing contract optimizes the chain and delivers a win–win situation for all the players in a video retail supply chain. Yao et al., 2008a and Yao et al., 2008b have argued that revenue-sharing contract improves supply chain performance. Linh and Hong (2009) have studied channel coordination through a revenue-sharing contract between a single retailer and a single supplier in a two-period newsboy problem and concluded that wholesale prices should be set lower than retail prices and the optimal revenue-sharing ratio should be increased linearly. Monahan (1984) has studied the use of all-unit quantity discount schedules to increase the order size in a two stage supply chain under the classical EOQ framework. Lee and Rosenblatt (1986) have extended the model by relaxing the lot-for-lot production assumption and imposing constraints on the price discount to remain below the selling price. Weng (1995) has showed that whole sale price discount does not provide coordination when demand is price-sensitive and transaction costs are functions of order quantities. The author has suggested the use of franchise fee and quantity discount simultaneously to restore coordination. Further, Wang and Wang (2005) have provided a generalized news-vendor model to use discount decisions as incentive policy to coordinate the supply chain. But to the best of author’s knowledge no one uses revenue sharing coupled with rebate as a tool for supply chain coordination. Again most of the cited papers consider only the effect of price, but it is also observed that the demand is not only dependent on price of the product but also on effort of the manufacturer. It is quite common in practice; the manufacturer applies selling effort to develop the market for the product such as stipulation of product information in market, advertisement, expenditure on social activities, greening effort, free repair or after-sales service. Coexistence of above factors is common in most of the retail sectors as stipulation of high effort to improve market demand. But a higher effort level sustains more cost to the individual paying such effort. From the above literature, it is also observed that consequence of supply chain coordination as well as influence of manufacturer’s extra marketing efforts are overlooked. Although use of rebate, thereby effects of these for individual benefit are studied extensively under a variety of modeling assumptions, none has discussed effects of rebate promotion and supply chain coordination simultaneously under manufacturer sales effort. We examine and compare three different coordination contracting approaches, DR&RS”, “DDR” and ”DR&ES”. The effectiveness of the contracting approach is verified with respect to supply chain coordination perspective. In “DR&RS”, the manufacturer offers customer rebate to the end customer and retailer compensates manufacturers loss by sharing a percentage of her revenue with manufacturer. In “DDR” manufacturer provides retailer rebate by reducing her wholesale price and as a consequence retailer also reduces her price to enhance demand of the product. In “DR&ES”, the manufacturer offers customer rebate to the end customer and each member in supply chain wants to promote the product by providing promotional effort. The purpose of the paper is to examine coordination of the supply chain when these coordination mechanisms are used. We have verified analytically that all the proposed coordination mechanisms can coordinate the system for linear demand. But for iso-elastic demand, DR&RS and DDR coordinate the system but DR&ES does not. Effectiveness, flexibility, equivalence and preference of proposed mechanism are discussed analytically. The rest of this paper is organized as follows: The model is formally developed for decentralized and integrated decision making in Section 2 and then coordination of the chain is analyzed under linear and iso-elastic demand. A final discussion, in Section 3, provides some comments on the main results obtained, on the shortcomings of the model and some suggestions for future research. The proofs are reported in the appendices.

To improve the coordination between the manufacturer and the retailer, there are increasing interests to examine various types of supply chain contracts to achieve channel coordination as well as win–win situations for each partner of the chain. This observation, together with the observed industrial practices, has motivated us to examine power of above three hybrid contracts both for linear and iso-elastic price and effort sensitive demand. We have studied the impact of various forms of rebate and the manufacturer effort on supply chain performance and efficiency. It is established that supply chain profits are improved by the use of retailer rebate or customer rebate. But, in this paper we prove that in combination with revenue sharing, price discount or effort (cost sharing) sharing, retailer or customer rebate can coordinate the chain also. Three new coordination mechanisms are proposed, namely DR&RS, DDR and DR&ES. We proved that DR&RS and DDR are equivalent and both the retailer and the manufacturer have equal opportunity to gain extra profit. Out comes of the mechanisms are demand sensitive as DR&ES contract does not coordinate the system for iso-elastic demand, but DR&RS and DDR coordinate the system for linear as well as iso-elastic demand. The Contributions of the paper to the literature are as follows: first, in previous researches rebate induced promotional policies are applied thereby impacts of these are analyzed on individual activities and profits of chain members. Obviously, coordination issue for overall performance of the chain is neglected. Here promotional policies are used aimed at improved performance of entire chain and improved performances of each chain member also. Secondly, revenue sharing contract used here is different from traditional revenue sharing contract in the sense that downstream channel members provide a percentage of their generated revenues to upstream channel members without claiming any reduction on decentralized wholesale price of upstream channel member but in traditional revenue sharing contract, it is necessary that the whole sale price of the manufacturer must be less than the marginal cost of the product. Thirdly, it is proved that if members of the supply chain operate jointly with retailer’s decentralized retail price and manufacturer’s decentralized wholesale price and apply rebate then also the channel conflict can be eliminated. From the perspective of operation and marketing management this situation is acceptable because the profit of entire supply chain is maximized and the surplus profit is allocated arbitrarily. That is, entire channel profit is maximized and win–win outcomes for all channel members are realized simultaneously. Obviously this result is acceptable for its intuitive appeal. Fourthly, although by strategically implementing either DR&RS or DDR the manufacturer and the retailer can achieve full channel coordination and improve their individual profits, still manufacturer prefers DDR or DR&RS, whereas the retailer prefers DR&ES for linear demand, but for which particular values of revenue sharing fractions and discount fractions the chain members settle will depend obviously on their bargaining powers. Member having more bargaining power will definitely receive more profit surplus. Fifthly, when push promotion DDR is applied the supply chain is coordinated and win–win outcome is achieved and to eliminate channel conflict and to achieve improved profit, the manufacturer and the retailer cooperate actively by complementing one another through contribution to invariant rebate that is provided to customers. Sixthly, an interesting objective of DR&RS and DDR policies revealed in this paper is its transitional behavior from the strange phenomena achieved under iso-elastic demand that the Stacklberg leader, the manufacturer obtains less profit than the retailer, to the anticipated normal situation. Under iso-elastic demand by applying coordination policy, the manufacturer can also achieve higher profit compare to the retailer without violating system coordination. In addition, several suggestions for future research are given. On the demand side incorporation of either fuzzy or stochastic properties can be considered. It will be interesting to analyze the performance of propose contract by considering the retailer as a Stackelberg leader under iso-elastic demand. Moreover, more investigations are warranted on the long term effect of promotional programs on demand as in practice the effect of promotions decrease over time. On the supply side, the use of “bargaining game theory” to illustrate the bargaining power of the cooperative dyadic members and the resulting effect on the cooperation and solutions can also be worth mentioning for future research.