Optimization and Coordination of Fresh Product Supply Chains with Freshness‐Keeping Effort

We consider a supply chain in which a distributor procures from a producer a quantity of a fresh product, which has to undergo a long‐distance transportation to reach the target market. During the transportation process, the distributor has to make an appropriate effort to preserve the freshness of the product, and his success in this respect impacts on both the quality and quantity of the product delivered to the market. The distributor has to determine his order quantity, level of freshness‐keeping effort, and selling price, by taking into account the wholesale price of the producer, the cost of the freshness‐keeping effort, the likely spoilage of the product during transportation, and the possible demand for the product in the market. The producer, on the other hand, has to determine the wholesale price based on its effect on the order quantity of the distributor. We develop a model to study this problem, and characterize each party's optimal decisions in both decentralized and centralized systems. We further develop an incentive scheme to facilitate coordination between the two parties. Computational results are reported to show the effects of freshness‐keeping efforts.     

Supply Chain Management of Fresh Products with Producer Transportation*

This article considers a class of fresh‐product supply chains in which products need to be transported by the upstream producer from a production base to a distant retail market. Due to high perishablility a portion of the products being shipped may decay during transportation, and therefore, become unsaleable. We consider a supply chain consisting of a single producer and a single distributor, and investigate two commonly adopted business models: (i) In the “pull” model, the distributor places an order, then the producer determines the shipping quantity, taking into account potential product decay during transportation, and transports the products to the destination market of the distributor; (ii) In the “push” model, the producer ships a batch of products to a distant wholesale market, and then the distributor purchases and resells to end customers. By considering a price‐sensitive end‐customer demand, we investigate the optimal decisions for supply chain members, including order quantity, shipping quantity, and retail price. Our research shows that both the producer and distributor (and thus the supply chain) will perform better if the pull model is adopted. To improve the supply chain performance, we propose a fixed inventory‐plus factor (FIPF) strategy, in which the producer announces a pre‐determined inventory‐plus factor and the distributor compensates the producer for any surplus inventory that would otherwise be wasted. We show that this strategy is a Pareto improvement over the pull and push models for both parties. Finally, numerical experiments are conducted, which reveal some interesting managerial insights on the comparison between different business models.     

Supply Chain Coordination in the Presence of Gray Markets and Strategic Consumers

The practice of diverting genuine products to unauthorized gray markets continues to challenge companies in various industries and creates intense competition for authorized channels. Recent industry surveys report that the abuse of channel incentives is a primary reason for the growth of gray market activities. Therefore, it is crucial that companies take the presence of gray markets into consideration when they design contracts to distribute products through authorized retailers. This issue has received little attention in the extensive literature on contracting and supply chain coordination. In this study, we analyze the impacts of gray markets on two classic contracts, wholesale price and quantity discount, in a supply chain with one manufacturer and one retailer when the retailer has the opportunity to sell to a domestic gray market. Our analysis provides interesting and counterintuitive results. First, a classic quantity‐discount contract that normally coordinates the supply chain can perform so poorly in the presence of a gray market that the supply chain would be better off using a wholesale price contract instead. Second, the presence of gray market can also degrade the performance of the wholesale price contract; therefore, a more sophisticated contract is needed for coordinating the supply chain. We show that contracts that solely depend on retailer's order quantity cannot coordinate the supply chain, and provide the conditions for coordinating the supply chain with price‐dependent quantity discount contracts. We also provide comparative statics and show that when there is a gray market, coordinating the supply chain enhances total consumer welfare.     

Competition and Coordination in a Two‐Channel Supply Chain

We study competition and coordination in a supply chain in which a single supplier both operates a direct channel and sells its product through multiple differentiated retailers. We study analytically the supply chain with symmetric retailers and find that the supplier prefers to have as many retailers as possible in the market, even if the retailers' equilibrium retail price is lower than that of the supplier, and even if the number of retailers and their cost or market advantage prevent sales through the direct channel. We find that the two‐channel supply chain may be subject to inefficiencies not present in the single‐channel supply chain. We show that several contracts known to coordinate a single‐channel supply chain do not coordinate the two‐channel supply chain; thus we propose a linear quantity discount contract and demonstrate its ability to perfectly coordinate the two‐channel supply chain with symmetric retailers. We provide some analytical results for the supply chain with asymmetric retailers and propose an efficient solution approach for finding the equilibrium. We find numerically that the supplier still benefits from having more retailers in the market and that linear quantity discount contracts can mitigate supply chain inefficiency, though they no longer achieve perfect coordination.     

具有两阶段生产模式和需求信息更新的供应链契约研究

针对二级供应链,在基于Stackelberg博弈的批发价契约中,分析了折扣价格与零售商最优提前订购量的关系及对契约双方期望收益的影响;设计了价格折扣与回购联合的协调契约,分析了供应链系统的最优提前生产量、供应链协调条件及协调契约下制造商和零售商的期望收益变化,并在协调契约不满足制造商的个体理性约束时,提出采用不对称Nash谈判模型设计两阶段生产与订购的回购契约,在保证供应链系统整体绩效最优的条件下,使制造商和零售商利润都能得到满意增长。研究表明,三级供应链实行两阶段订购的必要条件是分销商与零售商的最优提前订购量相等,与二级供应链相比,价格折扣契约下三级供应链效率更低,但价格折扣与回购联合的契约同样能协调三级供应链,该协调契约满足零售商与分销商激励相容约束。     

预测精度和成本双时变的短生命周期产品供应链优化与协调

对于提前期可压缩的短生命周期产品供应链,压缩提前期可以提高销售商的需求预测精度,但增加了制造商的生产成本,因而供应链面临何时订货、订多少,以及如何实现Pareto改进的挑战。通过建立数学模型并求解,分析了分散系统和集中系统的最优决策,进一步开发了一个激励方案以实现供应链成员之间的协调。研究结果表明:具有订货回馈与惩罚的动态批发价契约能够有效协调双时变参数供应链,契约参数α在一定范围内取值可实现供需双方共赢。     

Push and Pull Contracts in a Local Supply Chain with an Outside Market*

Wholesale price contracts are widely studied in a single supplier‐single retailer supply chain, but without considering an outside market where the supplier may sell if he gets a high enough price and the retailer may buy if the price is low enough. We fill this gap in the literature by studying push and pull contracts in a local supplier–retailer supply chain with the presence of an outside market. Taking the local supplier's maximum production capacity and the outside market barriers into account, we identify the Pareto set of the push and/or pull contracts and draw managerial implications. The main results include the following. First, the most inefficient point of the pull Pareto set cannot always be removed by considering both the push and pull contracts. Second, the supplier's production capacity plays a significant role in the presence of an outside market; it affects the supplier's negotiating power with the retailer and the coordination of the supply chain can be accomplished only with a large enough capacity. Third, the import and export barriers influence the supply chain significantly: (i) an export barrier in the local market and the supplier's production capacity influence the supplier's export strategy; (ii) a low import (resp., export) barrier in the local market can improve the local supply chain's efficiency by use of a push (resp., pull) contract; and (iii) a high import (resp., export) barrier in the local market encourages the supplier (resp., retailer) to bear more inventory risk.     

不确定需求下的冷链分销商最优决策

针对新鲜产品供应链 (冷链) 中分销商, 引入保鲜努力刻画分销商投入的保鲜工作, 考虑新鲜产品到达市场的数量与质量, 分析冷链分销商的最优决策问题.与前人研究相比, 本文使用加法形式需求函数刻画市场需求, 并使用相关企业数据验证加法形式需求函数合理性, 完善了冷链分销商决策问题的相关研究.研究发现, 当保鲜努力外生时, 分销商的最优订货数量和最优零售价格只与保鲜努力有关;当零售价格外生时, 分销商的最优保鲜努力与产品实际单位成本关于保鲜努力函数的一阶最优条件有关;当订货数量外生时, 分销商制定的零售价格随保鲜努力增加而增大, 所获得的利润也随保鲜努力递增, 但边际利润随保鲜努力递减.最后, 将所得结论应用于中国500强民营企业卓尔控股有限公司旗下的小雪冷链 (武汉) 物流有限公司, 为该公司提供相应的保鲜努力投入策略.     

Contracting and Coordination under Asymmetric Production Cost Information

We analyze a supply chain consisting of a supplier and a retailer. The supplier's unit production cost, which characterizes his type, is only privately known to him. When trading with the retailer, the supplier demands a reservation profit that depends on his unit production cost. We model this problem as a game of adverse selection. In this model, the retailer offers a menu of contracts, each of which consists of two parameters: the ordering quantity and the supplier's share of the channel profit. We show that the optimal contract depends critically on a surrogate measure—the ratio of the types’ reservation profit differential to their production cost differential. An important implication from our analysis is that information asymmetry alone does not necessarily induce loss in channel efficiency. The optimal contract can coordinate the supply chain as long as the low‐cost supplier's cost efficiency is neither much overvalued nor much undervalued in the outside market. We further discuss the retailer's preference of the supplier's type under different market conditions, as well as evaluate the effects of the supplier's reservation profit, the retail price, and the demand uncertainty on the optimal contract.     

回馈与惩罚契约下闭环供应链应对突发事件的协调性研究

考虑一个制造商和一个零售商组成的闭环供应链,在考虑随机性需求下,首先分析了回馈与惩罚契约对闭环供应链的协调作用;然后,探讨了回馈与惩罚契约对突发事件的协调作用,研究表明:基准的回馈与惩罚契约对突发事件将不再发挥协调作用,为此,给出了闭环供应链对突发事件的最优应对策略,并调整了原来的回馈与惩罚契约使其具有抗突发事件性。     

The Impact of Contracts and Competition on Upstream Innovation in a Supply Chain

We consider a supply chain with an upstream supplier who invests in innovation and a downstream manufacturer who sells to consumers. We study the impact of supply chain contracts with endogenous upstream innovation, focusing on three different contract scenarios: (i) a wholesale price contract, (ii) a quality‐dependent wholesale price contract, and (iii) a revenue‐sharing contract. We confirm that the revenue‐sharing contract can coordinate supply chain decisions including the innovation investment, whereas the other two contracts may result in underinvestment in innovation. However, the downstream manufacturer does not always prefer the revenue‐sharing contract; the manufacturer's profit can be higher with a quality‐dependent wholesale price contract than with a revenue‐sharing contract, specifically when the upstream supplier's innovation cost is low. We then extend our model to incorporate upstream competition between suppliers. By inviting upstream competition, with the wholesale price contract, the manufacturer can increase his profit substantially. Furthermore, under upstream competition, the revenue‐sharing contract coordinates the supply chain, and results in an optimal contract form for the manufacturer when suppliers are symmetric. We also analyze the case of complementary components suppliers, and show that most of our results are robust.     

3PL参与的时变需求变质品三级供应链模型

随着现代物流业的发展,企业将一些业务如运输等外包已经成为参与当今市场竞争的一种手段和趋势,因此考虑包含第三方物流服务提供商（3PL）的供应链更具有现实和理论意义。但是现有文献很少考虑3PL对包含时间因素的变质品供应链模型的影响。基于此,本文建立了一个包含3PL的时变需求变质品三级供应链模型,并运用动态博弈理论求解了该模型的分散式下的均衡解。研究表明与制造商单独承担运输费用相比,由3PL承担运输费用使得产品的订货周期缩短,订货量减少。通过对比分散式决策和集中式决策下的最优解,研究发现考虑系统总体利润情况下,集中式决策的方式不能使该供应链达到协调。最后给出算例验证结论的正确性。     

Quantity Flexibility Contract in the Presence of Discount Incentive

We design a new contract, which we refer to as the QFi contract, that combines the quantity flexibility (QF) mechanism and the price‐only discount incentive. Under the QF contract, the buyer does not assume full responsibility for the forecast, yet the supplier guarantees the availability of the forecasted quantity and extra buffer inventory. In contrast, the price‐only discount contract places full inventory burden on the buyer. We show that the proposed QFi contract effectively balances the inventory risk for both the buyer and the supplier considering both the QF and discount mechanisms. We also show that the QFi contract is able to achieve supply chain coordination. More importantly, the QFi contract's coordinating price scheme does not require knowledge of demand distribution. We identify areas where the buyer and supplier may both benefit from implementing the QFi contract as opposed to the extant QF or price‐only (wholesale) discount contractual decisions in a decentralized supply chain. We also specify the conditions under which supply chain coordination can be achieved in a win‐win manner. We conclude with managerial implications and provide directions for future research.     

Supply chain coordination with information design

We consider the coordination of a supplier–retailer supply chain where, in addition to classical contract considerations, a supplier decides the adoption of an information structure (IS) for the supply chain, with a higher-quality IS allowing the supply chain parties to obtain a more accurate demand forecast. Because a wholesale price contract cannot coordinate the supply chain due to misaligned incentives of supply chain parties, we explore what common coordinating contracts in the classical coordination literature can continue coordinating the supply chain with the IS adoption. Interestingly, our analysis appears to reveal the power of simplicity: some simple classical coordinating contracts (e.g., the buy-back and revenue-sharing contracts), though not designed with the IS consideration, still coordinate the supply chain, whereas other more complicated classical contracts (e.g., the quantity flexibility and sales rebate contracts) fail to do so. We derive a general condition for supply chain coordination and show that any contract with a newsvendor-like transfer payment can coordinate the supply chain.     

Hedging through index-based price contracts in commodity-based supply chains

This paper studies the optimal hedging strategy of risk-neutral firms in supply chain settings. We model a retailer procuring goods through index-based price contracts from two commodity processors. The processors’ input commodity prices are random and correlated. The retailer faces price-sensitive demand curves; therefore, it controls product demand through retail pricing in the final product market. We characterize the optimal contracting terms for the processors and show that they prefer to hedge part of their exposure to the commodity price risk. The optimal contract for processor comprises a processing margin independent of the commodity price volatility and a hedge ratio that is a function of the commodity price volatility and the products substitution factor. We uncover a new rationale for hedging in settings where downstream firms have pricing power; both processors and the retailer benefit from the retailer’s pricing power when their margins are linked to input prices; an index-based price contract is a means to link the processors’ and the retailer’s margins. We further investigate how different market parameters affect the optimal hedge ratios and extend our model to settings with random market sizes and asymmetric substitution for final products.     

产品召回供应链中线性保险合约与订货决策

考虑一个由单供应商和单制造商组成的二级供应链,在不确定市场需求情形下考虑产品召回,站在制造商角度研究供应链线性保险合约下的最优订货决策以及最优线性保险合约决策。研究表明,最优的订货决策与产品召回概率以及线性保险系数相关,存在唯一的最优订货量来最大化制造商的利润。对于密度函数倒数的导数较大的一般需求分布函数,最优的线性保险系数与线性保险合约的固定费用以及产品召回概率有关。当产品召回概率和线性保险合约的固定费用均较小时或者产品召回概率较大但线性保险合约的固定费用适中时,制造商通过选择线性保险合约可以改善自己的利润。     

考虑技术研发和物流配送的医药供应链组合契约协调模型研究

两票制政策的实施使医药供应链管理模式发生了重大变化,也使供应链成员的决策更加复杂。为了确保药品高效、及时、持续的供应,本文研究由一个医药生产企业、一个医药流通企业和一个药店/医院组成的三级供应链的医药定价与协调问题。考虑市场需求受医药生产企业的技术研发和医药流通企业的物流配送影响的情况下,以合作决策的市场价格和最优利润为基准,采用收益共享+数量折扣组合契约作为激励机制,建立了分散决策下供应链组合契约协调模型,探究技术研发和物流配送能力对医药供应链及成员的影响。通过算例分析发现：实施收益共享+数量折扣组合契约策略可以有效的优化和协调医药供应链,能够激励医药生产企业努力提升技术研发水平,激励医药流通企业努力提升物流水平,实现整个医药供应链的帕累托最优。     

两零售商竞争下多因素同时扰动的供应链协调研究

本文研究了由一个制造商两个竞争零售商组成的供应链在百川德博弈下,生产成本、市场需求和价格敏感系数同时扰动的协调机制,考虑了线性数量折扣契约对供应链的协调作用。研究表明,当三因素同时发生扰动后, 集权式供应链中线性数量折扣契约可以协调供应链,而在分散式供应链中,原来的协调契约不具有鲁棒性,制造商只有采用新的线性数量折扣契约,分散式供应链才能实现协调。 最后用一个算例验证了结论。     

考虑资金收益情况下的供应链回购契约

在制造商的资金收益率大于零售商资金收益率的情况下,以报童模型为基础,研究了资金收益对回购契约的影响.系统预期利润变为与批发价相关,利用拉格朗日方程求解了满足零售商参与约束、同时使系统和制造商预期利润取得最大值的契约参数.与不考虑资金收益情况下的供应链协调不同的是:订货批量大于相应批发价下不考虑零售商参与约束的最优订货批量;若零售商的保留利润一定,则回购价增大;回购价可以大于批发价,批发价可以小于制造商的边际生产成本.     

On the Advantage of Quantity Leadership When Outsourcing Production to a Competitive Contract Manufacturer

This study investigates a supply chain comprising an original equipment manufacturer (OEM) and a contract manufacturer (CM), in which the CM acts as both upstream partner and downstream competitor to the OEM. The two parties can engage in one of three Cournot competition games: a simultaneous game, a sequential game with the OEM as the Stackelberg leader, and a sequential game with the CM as the Stackelberg leader. On the basis of these three basic games, this study investigates the two parties' Stackelberg leadership/followership decisions. When the outsourcing quantity and wholesale price are exogenously given, either party may prefer Stackelberg leadership or followership. For example, when the wholesale price or the proportion of production outsourced to the CM is lower than a threshold value, both parties prefer Stackelberg leadership and, consequently, play a simultaneous game in the consumer market. When the outsourcing quantity and wholesale price are decision variables, the competitive CM sets a wholesale price sufficiently low to allow both parties to coexist in the market, and the OEM outsources its entire production to this CM. This study also examines the impact of the supply chain parties' bargaining power on contract outcomes by considering a wholesale price that is determined via the generalized Nash bargaining scheme, finding a Stackelberg equilibrium to be sustained when the CM's degree of bargaining power is great and the non‐competitive CM's wholesale price is high.