Temporary Hubs for the Global Vehicle Supply Chain in Humanitarian Operations

We model the global vehicle supply chain of an International Humanitarian Organization (IHO) with a dynamic hub location model across monthly periods. We use actual vehicle data from the International Federation of the Red Cross to feed our model and provide insights into IHO secondary support demand. We find that secondary support demand for items such as vehicles is different from primary beneficiary demand for items such as water and food. When considering disaster response and development program demand simultaneously (disaster cycle management), our results illustrate that keeping a lean centralized hub configuration with an option for temporary hubs in mega disaster locations can reduce overall supply chain costs over a long time horizon. We also show that it is possible to structure a supply chain to take operational advantage of earmarked funding. This research lays the groundwork for using optimization models to analyze disaster cycle management.     

Designing Efficient Infrastructural Investment and Asset Transfer Mechanisms in Humanitarian Supply Chains

We analyze the efficacy of different asset transfer mechanisms and provide policy recommendations for the design of humanitarian supply chains. As a part of their preparedness effort, humanitarian organizations often make decisions on resource investments ex ante because doing so allows for rapid response if an adverse event occurs. However, programs typically operate under funding constraints and donor earmarks with autonomous decision‐making authority resting with the local entities, which makes the design of efficient humanitarian supply chains a challenging problem. We formulate this problem in an agency setting with two independent aid programs, where different asset transfer mechanisms are considered and where investments in resources are of two types: primary resources that are needed for providing the aid and infrastructural investments that improve the operation of the aid program in using the primary resources. The primary resources are acquired from earmarked donations. We show that allowing aid programs the flexibility of transferring primary resources improves the efficiency of the system by yielding greater social welfare than when this flexibility does not exist. More importantly, we show that a central entity that can acquire primary resources from one program and sell them to the other program can further improve system efficiency by providing a mechanism that facilitates the transfer of primary resources and eliminates losses from gaming. This outcome is achieved without depriving the individual aid programs of their decision‐making autonomy while maintaining the constraints under which they operate. We find that outcomes with centralized resource transfer but decentralized infrastructural investments by the aid programs are the same as with a completely centralized system (where both resource transfer and infrastructural investments are centralized).     

Humanitarian Funding in a Multi‐Donor Market with Donation Uncertainty

This study analyzes the trade‐off between funding strategies and operational performance in humanitarian operations. If a Humanitarian Organization (HO) offers donors the option of earmarking their donations, HO should expect an increase in total donations. However, earmarking creates constraints in resource allocation that negatively affect HO's operational performance. We study this trade‐off from the perspective of a single HO that maximizes its expected utility as a function of total donations and operational performance. HO implements disaster response and development programs and it operates in a multi‐donor market with donation uncertainty. Using a model inspired by Scarf's minimax approach and the newsvendor framework, we analyze the strategic interaction between HO and its donors. The numerical section is based on real data from 15 disasters during the period 2012–2013. We find that poor operational performance has a larger effect on HO's utility function when donors are more uncertain about HO's expected needs for disaster response. Interestingly, increasing the public awareness of development programs helps HO to get more non‐earmarked donations for disaster response. Increasing non‐earmarked donations improves HO's operational efficiency, which mitigates the impact of donation uncertainty on HO's utility function.     

Buttressing Supply Chains against Floods in Asia for Humanitarian Relief and Economic Recovery

Floods are the most frequent category of disasters worldwide. Among all geographic regions, Asia has suffered the most. While there are several ongoing humanitarian efforts and initiatives, we believe there is a new opportunity to coordinate “last mile” humanitarian efforts in the event of a flood using micro‐retailers. Because micro‐retailers are the “last mile” nodes in traditional retail supply chains in many Asian countries, we propose the use of social enterprise to buttress these supply chains for distribution of essential goods by coordinating with micro‐retailers before and after floods. We also present a stylized model to quantify the benefits of doing so.     

Introduction to the Special Issue on Humanitarian Operations and Crisis Management

The Genesis of this Special Issue came from the Board of the POMS College on Humanitarian Operations and Crisis Management (HO&CM). It was seen as a necessary initiative to define the field and examine research opportunities. This Special Issue shows that humanitarian operations pose challenges for P/OM researchers and practitioners that differ markedly from those of conventional supply chains associated with profitable enterprises. On the basis of the eight articles in this Special Issue, we have described and demonstrated the unique characteristics of the POM/HO&CM interaction. We have also identified those attributes that tend to overlap with conventional aspects of POM. In addition to wanting to be cost effective, the issue of equity fairness is pervasive in humanitarian operations, and so is the need to always base considerations on “last‐mile logistics,” that is, getting aid to those in most need. Research is essential to determine how to train researchers to scout out and map the territory of the real problems. One of the most vexing problems is the lack of robust data in the humanitarian domain which is as richly varied as the types of disasters that can occur.     

Information Diffusion among Agents: Implications for Humanitarian Operations

The basis for this article is an information‐processing view of the UN's cluster approach. We use agent‐based modeling and simulations to show that clusters, if properly utilized, encourage better information flow and thus facilitate effective response to disasters. The article intends to turn the attention of the humanitarian community to the importance of sharing information and the role of cluster leads in facilitating humanitarian aid. Our results indicate that if cluster leads act as information hubs, information reaches its target faster, enabling a prompt humanitarian response. In addition, we show that information quality is critical for effective resource utilization—if cluster leads filter information, it moves faster. We also found evidence that the willingness to exchange information plays a larger role in transmitting information than that of an information hub, particularly during later stages of response operations.     

Order Stability in Supply Chains: Coordination Risk and the Role of Coordination Stock

The bullwhip effect describes the tendency for the variance of orders in supply chains to increase as one moves upstream from consumer demand. We report on a set of laboratory experiments with a serial supply chain that tests behavioral causes of this phenomenon, in particular the possible influence of coordination risk. Coordination risk exists when individuals' decisions contribute to a collective outcome and the decision rules followed by each individual are not known with certainty, for example, where managers cannot be sure how their supply chain partners will behave. We conjecture that the existence of coordination risk may contribute to bullwhip behavior. We test this conjecture by controlling for environmental factors that lead to coordination risk and find these controls lead to a significant reduction in order oscillations and amplification. Next, we investigate a managerial intervention to reduce the bullwhip effect, inspired by our conjecture that coordination risk contributes to bullwhip behavior. Although the intervention, holding additional on‐hand inventory, does not change the existence of coordination risk, it reduces order oscillation and amplification by providing a buffer against the endogenous risk of coordination failure. We conclude that the magnitude of the bullwhip can be mitigated, but that its behavioral causes appear robust.     

An Experimental Investigation of Pull Contracts in Supply Chains

In this study, I investigate supply chain contracts in a setting where a supplier uses its inventory to directly satisfy a retailer's demand. These “pull” contracts have increased in popularity in practice but have not been studied experimentally. In a controlled laboratory setting, I evaluate a wholesale price contract and two coordinating contracts. The data suggest that the benefit of the two coordinating contracts over the wholesale price contract is less than the standard theory predicts, and that retailers, in the two coordinating contracts, exhibit a systematic bias of setting the coordinating parameter too low, and the wholesale price too high, relative to the normative benchmarks. In an effort to explain this deviation, I explore three behavioral models and find that loss aversion and reference dependence fit the data well. I empirically test this result in a follow‐up experiment, which directly controls for loss aversion and reference dependence, and observe that retailers make significantly better decisions. Lastly, I administer a number of experiments which reduce the complexity of the problem, curtail the amount of risk, and increase the level of decision support, and find that none improve decisions relative to the treatment that controls for loss aversion and reference dependence.     

Erratum: Amplification in Service Supply Chains: An Exploratory Case Study from the Telecom Industry

This erratum contains the appendix that was omitted from the original paper by H. Akkermans and B. Vos, “Amplification in service supply chains: an exploratory study from the telecom industry”, Production and Operations Management, 12, 2, 204–223.     

Problem Formulation and Solution Mechanisms: A Behavioral Study of Humanitarian Transportation Planning

When dealing with urgent, ill‐defined problems, such as rapidly evolving emergency situations, operations managers have little time for problem formulation or solution. While the mechanisms by which humans formulate and solve problems have been described, mechanisms for rapid, concurrent formulating and solving are not well understood. This study investigates these mechanisms through a field study of transportation planning in a humanitarian response setting. The findings show that the problem is solved through greedy search and formulated through sensemaking, in which search enables updates to an evolving problem formulation, and the formulation directs and limits the search process. This study explores the implications of these findings for the development of better problem formulation processes and problem‐solving strategies for urgent and ill‐defined operations management problems.     

Managing Disruption Risks in Supply Chains

There are two broad categories of risk affecting supply chain design and management: (1) risks arising from the problems of coordinating supply and demand, and (2) risks arising from disruptions to normal activities. This paper is concerned with the second category of risks, which may arise from natural disasters, from strikes and economic disruptions, and from acts of purposeful agents, including terrorists. The paper provides a conceptual framework that reflects the joint activities of risk assessment and risk mitigation that are fundamental to disruption risk management in supply chains. We then consider empirical results from a rich data set covering the period 1995–2000 on accidents in the U. S. Chemical Industry. Based on these results and other literature, we discuss the implications for the design of management systems intended to cope with supply chain disruption risks.     

Power Structure and Profitability in Assembly Supply Chains

This paper studies the impact of supply chain power structure on firms' profitability in an assembly system with one assembler and two suppliers. Two power regimes are investigated—in a Single Power Regime, a more powerful firm acts as the Stackelberg leader to decide the wholesale price but not the quantity whereas in a Dual Power Regime, both the price and quantity decisions are granted to the more powerful firm. Tallying the power positions of the three firms, for each power regime we study three power structures and investigate the system's as well as the firms' preference of power. We find that when the assembler is the most powerful firm among the three, the system‐wide profit is the highest and so is the assembler's profit. The more interesting finding is that, if the assembler is not the most powerful player in the system, more power does not necessarily guarantee her a higher profit. Similarly, a supplier's profit can also decrease with the power he has. These results contrast with the conclusion for serial systems, where a firm always prefers more power. We also find that when both suppliers are more (less) powerful than the assembler, it can be beneficial (indifferent) for everyone if the two suppliers merge into a mega supplier to make decisions jointly. When the assembler is more powerful than one supplier and less so than the other, it is always better for the system to have the two suppliers merge, and for each individual firm, merging is preferred if the firm becomes the more powerful party after merging.     

Supply Chains and Global Health: An Imperative for Bringing Operations Management Scholarship into Action

Many people in developing countries do not have access to effective vaccines, medicines, and other life‐saving health technologies. Shortage of health care workers, severe financial constraints, and lack of awareness are some of the major obstacles that prevent higher access. However, ineffective and poorly designed supply chains for purchasing and distributing the medicines, vaccines, and health technologies are one of the most important barriers to increasing access. We argue that the ineffectiveness of the global health supply chain can be attributed largely to: coordination problems across multiple stakeholders with widely divergent objectives, lack of careful supply chain design, and use of myopic operational objectives and metrics. The operations management research community can contribute to improving this by applying existing knowledge to the field of global health delivery and by researching new frameworks of analysis which would then become the cornerstones for policy advice to those who design, operate, or finance these supply chains.     

Joint Mail‐In Rebate Decisions in Supply Chains Under Demand Uncertainty

We study the joint decisions of offering mail‐in rebates (MIRs) in a single‐manufacturer–single‐retailer supply chain using a game theoretic framework. Either party can offer an MIR to the end consumer if it is in his best interest. The consumer demand is stochastic and depends on the product price and the amount of MIRs. When the retail price is exogenous, we show the existence of a unique Nash equilibrium under both additive and multiplicative demand functions and characterize it completely. We show that any of the following four scenarios can be the equilibrium: both parties offer MIR, only one party offers MIR, none offers MIR. When the retail price is a decision variable for the retailer and the rebate redemption rate increases with the amount of MIR, we once again prove the existence of a unique Nash equilibrium where both the retailer and the manufacturer offer MIRs. Using a numerical study, we show that the average post‐purchase price of the product is higher not only than the perceived pre‐purchase price but also than the newsvendor optimal price without an MIR. This implies that an MIR makes a product look cheaper while the consumers actually pay more on average.     

Value of Information in Closed Loop Supply Chains

We explore the value of information (VOI) in the context of a firm that faces uncertainty with respect to demand, product return, and product recovery (yield). The operational decision of interest in matching supply with demand is the quantity of new product to order. Our objective is to evaluate the VOI from reducing one or more types of uncertainties, where value is measured by the reduction in total expected holding and shortage costs. We start with a single period model with normally distributed demands and returns, and restrict the analysis to the value of full information (VOFI) on one or more types of uncertainty. We develop estimators that are predictive of the value and sensitivity of (combinations of) different information types. We find that there is no dominance in value amongst the different types of information, and that there is an additional pay‐off from investing in more than one type. We then extend our analysis to the multi‐period case, where returns in a period are correlated with demands in the previous period, and study the value of partial information (VOPI) as well as full information. We demonstrate that our results from the single period model (adapted for VOPI) carry‐over exactly. Furthermore, a comparison with uniformly distributed demand and return show that these results are robust with respect to distributional assumptions.     

Quality Management in Multi‐Level Supply Chains with Outsourced Manufacturing

Outsourcing stretches supply chains longer with added contract manufacturers responsible for the manufacturing of parts and final products. Should a firm change its quality management approach as its supply chain becomes longer with outsourced manufacturing? This paper studies a brand owner's optimal choice between two commonly used quality management approaches: an inspection‐based approach and an external failure‐based approach, in two supply chains – a dyadic supply chain and a multi‐level supply chain where the brand owner outsources manufacturing to an independent contract manufacturer. Our study finds that the brand owner's optimal choice between the two quality management approaches could be opposite in the two supply chains. Specifically, we show that if agency costs exist between the contract manufacturer and the brand owner, the brand owner may prefer an inspection‐based approach in the multi‐level supply chain in contrast to preferring an external failure‐based approach in the dyadic supply chain. In particular, inspections can be effective for the brand owner to limit the manufacturer's profit by excluding defective finished products and components, which in turn reduce agency costs in the multi‐level supply chain. Hence, the efficiency of an inspection‐based approach relative to an external failure‐based approach can be higher in the multi‐level supply chain as compared to the dyadic one. Our findings suggest that firms should adjust to changes in supply chain structures and re‐evaluate the efficiencies of different quality management approaches accordingly.     

Price,Rebate, and Returns Supply Contracts for Coordinating Supply Chains with Price‐Dependent Demands

Channel rebates and returns policies are common mechanisms for manufacturers to entice retailers to increase their order quantities and sales ultimately. However, when the underlying demand depends on the retail price, it has been known that channel coordination cannot be achieved if only one of these mechanisms is deployed. In this article, we show that a policy that combines the use of wholesale price, channel rebate, and returns can coordinate a channel with both additive and multiplicative price‐dependent demands. In addition to determining the sufficient conditions for the contract parameters associated with the equilibrium policy, we show that multiple equilibrium policies for channel coordination exist. We further explore how the equilibrium policy can be adjusted to achieve Pareto improvement. Other issues such as the maximum amount of expected profit that the manufacturer can share under the coordinated channel, the structural properties of the contracts under both the additive and multiplicative price‐dependent demand functions are also discussed.     

供应链中销售商不同竞争地位的比较研究

本文在确定性需求的假设下,基于销售商竞争地位的不同,对由一个制造商和两个供应商组成的供应链进行分析,得出了销售商谋求不同竞争地位应满足的不同条件,比较了不同竞争地位情况下相对应的社会福利、消费者剩余和产业利润等。     

供应链中转节点物流能力计划问题研究

针对供应链中转节点的物流要素能力中的处理能力、流通量等决定因素进行了较为深入的理论分析;并且采用排队论的相关理论构建了具体的理论模型,得到了使得系统利润最大的中转节点的最优处理能力及最优流量。这一理论研究结果,为进一步研究供应链物流能力中连线的流通能力、各环节能力的匹配等决定因素奠定了理论基础,同时对于确定企业的物流要素能力指标中的处理能力以及流量等提供了一定的理论指导。