An integrated supplier-buyer model for improving supply chain coordination

This study develops a decision support model that can be used by a supplier in making production and price decisions at contract renewal times in a supply chain environment. The supplier first makes aggregate production decisions with a special attempt to estimate buyer commitments, and then determines the price of the item so as to satisfy his own profit and buyer cost reduction expectations simultaneously. Mathematical programming models are designed to achieve these in accordance with the contract terms. The main emphasis is placed upon the conceptual and negotiation aspects of the models, and some solution procedures are cited from previous studies. Then the approach is implemented in the biggest electric motor manufacturer in Turkey which has a large number of buyers in household appliances sector, and it is shown to be a useful tool for developing fair partnership.     

A discussion on economic ordering policy of deteriorated item for vendor and buyer

Yang and Wee (Economic ordering policy of deteriorated item for vendor and buyer: an integrated approach. Prod. Plan. & Cont., 2000, 11(5), 474–480) proposed an ordering policy for a vendor--buyer integrated model. This note examines the cost component of Yang and Wee's model and gives some insight on the derivation of the holding cost function. We have discovered that their model violates the positive holding cost characteristic and the total quantity-equality characteristic. A proposal to eradicate the problem is given.     

An Analysis of Scoring and Buyer‐Determined Procurement Auctions

In procurement auctions, the object for sale is a contract, bidders are suppliers, and the bid taker is a buyer. The suppliers bidding for the contract are usually the current supplier (the incumbent) and a group of potential new suppliers (the entrants). As the buyer has an ongoing relationship with the incumbent, he needs to adjust the bids of the entrants to include non‐price attributes, such as the switching costs. The buyer can run a scoring auction, in which suppliers compete on the adjusted bids or scores, or, he can run a buyer‐determined auction, in which suppliers compete on the price, and the buyer adjusts a certain number of the bids with the non‐price attributes after the auction to determine the winner. Unless the incumbent has a significant cost advantage over the entrants, I find that the scoring auction yields a lower average cost for the buyer, if the non‐price attributes are available. If the non‐price attributes are difficult or expensive to obtain, the buyer could run a buyer‐determined auction adjusting only the lowest price bid.     

Opportunism in buyer–supplier exchange: a critical examination of the concept and its implications for theory and practice

Abstract

Claims that opportunism is widespread in the process of buyer–supplier exchange are commonplace, but direct supporting evidence for such claims is largely absent from the relevant literature. This article offers a critique of the treatment of opportunism in supply chains by re-establishing the importance of guile in the concept and investigates existing published, empirical measures of buyer and supplier opportunistic behaviour. This article offers evidence that, despite the frequency with which the concept is discussed in the literature and applied in research and the emphasis given to the risks it generates for management, opportunism with guile between buyers and suppliers appears to be rare in practice. This article is the first critical assessment of the concept’s treatment in the Operations Management field, and it argues that practitioners are currently being poorly advised with respect to the phenomenon, as well as drawing conclusions for both practitioners and researchers that differ radically from the prevailing consensus on the subject.     

A multiple buyer – supplier relationship in the context of SMEs’ digital supply chain management*

Abstract

By underlining the relevance of the use of ICTs, knowledge sharing and electronic markets for SMEs, it emerges the need for stimulating a debate on digitisation process of supply chain management (SCM). Electronic infrastructure in the service sector are reducing each kind of cost and improving multiply buyer–supplier relationships, facilitating negotiations and transactions. However, since the coordination costs are still high, the use of ICTs is limited. This phenomenon thus attracts the interests of scholars and practitioners. Although it still needs to further investigate. Especially, the optimal use of ICTs within SMEs’ SCM have not been studied yet. Therefore, by leveraging on four proxies: ICTs specialised human resources, knowledge sharing activities, buyer–supplier relationships, adoption of electronic markets this optimal was analysed via structural equation modelling based on a sample of 1254 SMEs operating in the service sector in Italy.     

Managing Risk of Supply Disruptions: Incentives for Capacity Restoration

A supplier facing the prospect of disruption has to decide whether or not to invest in restoration capability. With restoration capability, if disruption occurs, additional costly effort can be exerted to rebuild capacity, although its outcome is uncertain. We study how a firm (buyer) can use incentive mechanisms to motivate a supplier's investment in capacity restoration, and compare this approach with the traditional approach of diversifying part of the order to an expensive but reliable supplier. Under a Restoration Enhancement (RE) strategy, the buyer uses price and/or order quantity incentives to encourage the supplier's restoration investment decision. Two different cases are considered—when the incentive is committed to ex ante (prior to disruption) and when it is committed to ex post (after disruption). In contrast, under a Supplier Diversification (SD) strategy, the buyer splits orders between a reliable supplier and an unreliable supplier to hedge against the disruption risk. Here, the buyer does not provide any separate incentive to the unreliable supplier. Our analysis indicates that under the RE strategy, where the buyer offers incentives, both the buyer and the supplier (weakly) prefer the ex ante commitment over the ex post one. Furthermore, the RE strategy is preferred over the SD strategy when the unreliable supplier's restoration outcome is more predictable or when a high restoration outcome is more likely. However, the buyer's preference for the SD strategy increases as market demand increases.     

With or Without Forecast Sharing: Competition and Credibility under Information Asymmetry

Forecast sharing among trading partners lies at the heart of many collaborative and contractual supply chain management efforts. Even though it has been praised in both academic and practitioner circles for its critical role in increasing demand visibility, some concerns remain: The first one is related to the credibility of forecast sharing, and the second is the fear that it may turn into a competitive disadvantage and induce suppliers to increase their price offerings. In this study, we explore the validity of these concerns under a supply chain with a competitive upstream structure, focusing specifically on (i) when and how a credible forecast sharing can be sustainable, and (ii) how it impacts on the intensity of price competition. To address these issues, we develop a supply chain model with a buyer facing a demand risk and two heterogeneous suppliers competing for order allocation from the buyer. The extent of demand is known only to the buyer. The buyer submits a buying request to the suppliers via a commonly used procurement mechanism called request for quotation (RFQ). We consider two variants of RFQ. In the first type, the buyer simply shares the estimated order quantity with no further specifications. In the second one, in addition to this, the buyer also specifies minimum and/or maximum order quantities. We fully characterize equilibrium decisions and profits associated with them under symmetric and asymmetric information scenarios. Our main findings are that the buyer can use a RFQ with quantity restrictions as a credible signal for forecast sharing as long as the degree of demand information asymmetry is not too high, and that, contrary to above concerns, the equilibrium prices that emerge between competing suppliers under asymmetric information may indeed increase if the buyer cannot share forecast information credibly with its upstream partners.     

Enabling SMEs to take full advantage of e-business

Electronic business is rapidly changing the relationships between supply chain partners. This paper looks at what is needed to allow SMEs to participate fully in supply chain integration. First, current trends in supply chain integration, electronic commerce, and Internet support are examined. Next, the goals and results of a study are presented which addressed SME needs in fast moving consumer goods supply chains. These concepts are then integrated to determine a way forward for SMEs to participate in e-business. It is found that current Virtual Markets (web-sites or on-line communities that facilitate finding a buyer or seller and track orders) address some customer - supplier relationships but need many enhancements before they can support fully integrated supply chains.     

Supplier Selection via Tournaments

In this paper, we study the performance of a sourcing mechanism gaining popularity in industrial procurement environments; a tournament. Under a tournament, a buyer initially procures her parts from two suppliers with possibly different quality levels, for T time periods, i.e., she parallel sources. During this time, the buyer is able to observe noisy signals about the suppliers' quality. At time T, she selects the supplier with the highest observed performance and awards it the remainder of her business. We characterize the optimal duration of the tournament as a function of various market parameters, including information and investment costs. Furthermore, we demonstrate that a tournament can be more profitable for the buyer than selecting the highest quality supplier at time T = 0 and sole sourcing entirely.     

Note on: An integrated vendor–buyer cooperative inventory model for items with imperfect quality

Huang [Huang, C., 2002. An integrated vendor–buyer cooperative inventory model for items with imperfect quality. Production Planning and Control, 13 (4), 355–361] proposes an integrated inventory model which allows a vendor and a buyer to minimise their expected integrated total cost function when the vendor's production process is not perfect. This note identifies two errors in the paper and provides a reformulation of the model.     

Information Acquisition and Voluntary Disclosure in an Export‐Processing System

We study a strategic information management problem in the export‐processing trade, where the buyer controls the raw material input and sales and the producer is responsible for production. The production is vulnerable to random yield risk. The producer can exert a costly effort to acquire the private yield rate information and discretionarily share it with the buyer. We develop a sequential Bayesian game model that captures three key features of the system—endogenous information endowment, voluntary disclosure, and ex post information sharing—a significant departure from the literature. The optimal disclosure strategy is driven by the trade‐off between the gains from Pareto efficiency improvement and self‐interested overproduction. It is specified by two thresholds on yield rate: only the middle‐yield producers (with yield rate between these two thresholds) share private information to improve supply‐demand match; the low‐ and high‐yield producers withhold information to extract excess input from the buyer. The buyer in response penalizes nondisclosure with reduced input and rewards information sharing with a larger order. This strategic interaction is further exacerbated by the double marginalization effect from decentralization, resulting in severe efficiency loss. We examine the effectiveness of three corrective mechanisms—vertical integration, mandatory disclosure, and production restriction—and reveal the costs of information suppressive effect and overinvestment incentive and the benefit from concessions on the processing fee. Our study endogenizes the asymmetric supply risk and provides the first attempt to rationalize the strategic interactions of informational and operational incentives in the export‐processing system.     

On revenue maximization with sharp multi-unit demands

We consider markets consisting of a set of indivisible items, and buyers that have sharp multi-unit demand. This means that each buyer \(i\) wants a specific number \(d_i\) of items; a bundle of size less than \(d_i\) has no value. We consider the objective of setting prices and allocations in order to maximize the total revenue of the market maker. The pricing problem with sharp multi-unit demand buyers has a number of properties that the unit-demand model does not possess, and is an important question in algorithmic pricing. We consider the problem of computing a revenue maximizing solution for two solution concepts: competitive equilibrium and envy-free pricing. For unrestricted valuations, these problems are NP-complete; we focus on a realistic special case of “correlated values” where each buyer \(i\) has a valuation \(v_iq_j\) for item \(j\), where \(v_i\) and \(q_j\) are positive quantities associated with buyer \(i\) and item \(j\) respectively. We present a polynomial time algorithm to solve the revenue-maximizing competitive equilibrium problem. For envy-free pricing, if the demand of each buyer is bounded by a constant, a revenue maximizing solution can be found efficiently; the general demand case is shown to be NP-hard.     

Vendor Selection with Bundling: A Comment*

In a recent article by Rosenthal, Zydiak, and Chaudhry (1995), a mixed integer linear programming model was introduced to solve the vendor selection problem for the case in which the vendor can sell items individually or as part of a bundle. Each vendor offered only one type of bundle, and the buyer could purchase at most one bundle per vendor. The model employed n(m+ 1) binary variables, where n is the number of vendors and m is the number of products they sell. The existing model can lead to a purchasing paradox: it may force the buyer to pay more to receive less. We suggest a reformulation of the same problem that (i) eliminates this paradox and reveals a more cost-effective purchasing strategy; (ii) uses only n integer variables and significantly reduces the computational workload; and (iii) permits the buyer to purchase more than one bundle per vendor.     

信息非对称条件下的质量预防决策分析

研究了不同信息条件下供应链的质量预防问题,在文献[1,2]建立的有关质量签约问题的优化模型基础上,把供应商作为委托人和购买商作为代理人建立了供应链的质量预防决策委托代理模型。其中,质量预防水平和供应商要求购买商的前向支付是供应商的决策变量,质量评价水平是购买商的决策变量。本文重点研究了了非对称信息下供应链的质量预防和前向支付问题,考虑了购买商质量评价信息隐匿情况,运用极大值原理推导了供应商的质量预防和前向支付的最优解。最后结合一个农机公司拖拉机销售问题进行了仿真计算和分析,对比了不同信息环境下的决策结果。     

Will More Purchasing Options Benefit Customers?

This paper considers the sale of a seasonal product in the face of strategic customers. At the beginning of the selling season, the retailer announces both the price p_h at which the product will be sold during the selling season and the post‐season clearance price p<p_h for unsold items. We analyze two operating regimes: The “no reservation regime” allows a buyer either to purchase the product at price p_h when he arrives or to enter a lottery to purchase at price p if the product remains unsold. The “reservation regime” offers each buyer one extra option than the no reservation regime: reserve the product for purchase at the clearance price p. If the buyer reserves the product under the reservation regime and if it remains unsold at the end of the selling season, then he is obligated to purchase it at price p. We consider a situation in which heterogeneous customers with probabilistic valuation arrive in accord with a Poisson process. We characterize the rational purchasing behavior wherein each arriving customer is strategic; each customer takes other customers' purchasing behavior into consideration. By considering the Nash equilibrium of this game, we show that strategic customer behavior can render the customer to be worse off and the retailer to be better off under the reservation regime, despite the fact that this regime offers one extra option (reservation) to a customer. Hence, more purchasing options do not necessarily benefit customers.     

Uncertainty about Uncertainty and Delay in Bargaining

We study a one‐sided offers bargaining game in which the buyer has private information about the value of the object and the seller has private information about his beliefs about the buyer's valuation. We show that this uncertainty about uncertainties dramatically changes the set of outcomes. In particular, second order beliefs can lead to a delay in reaching agreement even when the seller makes frequent offers. We show that not all types of second order beliefs lead to a delay. When the buyer assigns positive probability to the seller knowing the buyer's value, then delay not only can occur, but it must occur for a class of equilibria. However, in all other cases delay will never occur.     

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.     

An Exploratory Study of Procurement Strategies for Multi‐Item RFQs in B2B Markets: Antecedents and Impact on Performance

This research explores procurement strategies for multi‐item requests for quotation (RFQs) in business‐to‐business (B2B) markets using responses from 825 purchasing professionals. The study first establishes procurement strategies that differ based on their level of strategic emphasis, i.e., the importance that is placed on the pursuit of four strategic objectives. Underlying objectives, which are obtained via factor analysis, include the focus on price, security of supply, internal procurement efficiencies, and bundle building. Next, cluster analysis is used to derive prototypical strategic approaches. The three cluster groups that emerge possess the same relative ranking of the four objectives, but differ based on the intensity with which these objectives are pursued. The clusters are labelled as the three strategic groups of strategists, opportunists, and responders. The research then explores, using an industrial buyer behavior lens, the impact of environmental antecedents in determining a particular strategy. Environmental variables include purchase importance, market uncertainty, supply base availability, buyer bargaining power, item experience, and supply base experience. Finally, the study tests the impact of procurement strategy on the buyer's perceived performance, suggesting that strategists, placing more emphasis on the pursuit of strategic sourcing objectives, achieve better performance than opportunists and responders.     

Toward a Typology of Buyer–Supplier Relationships: A Study of the Computer Industry*

Buyer–supplier relationship typologies are useful analytical tools for purchasing managers in managing exchange relationships with suppliers and monitoring their purchasing portfolios. Existing buyer–supplier relationship typologies are mainly focused on either relational contents or power‐dependence and have limited empirical support for their performance implications. In this study, we developed an alternative buyer–supplier relationship typology that integrates both relational content and power‐dependence dimensions, resulting in four generic relationship types: market, power, autonomous‐link, and constrained‐link relationships. We then performed a longitudinal exploratory investigation of eight leading firms in the U.S. computer industry to explore the performance implications of the typology, using a combinatorial qualitative approach that leverages the strengths of case study research, content analysis, and quasi‐experimental design. The results suggest three theoretical propositions. First, the association between the type of buyer–supplier relationships and buyer firm performance varies such that constrained‐link relationships are superior in terms of operational efficiency while autonomous‐link relationships are superior in terms of product innovation. Second, the positive association between buyer–supplier relational contents (i.e., relationalism) and buyer firm operational efficiency is strengthened as the suppliers' dependence on the buyer firm increases. And finally, the positive association between buyer–supplier relationalism and buyer firm product innovation is weakened as the suppliers' dependence on the buyer firm increases.