SUPPLY CHAIN INFORMATION SHARING IN A VENDOR MANAGED INVENTORY PARTNERSHIP

Vendor Managed Inventory (VMI) involves the vendor making the replenishment decision for products supplied to a customer based on various inventory and supply chain policies. Information sharing between supply chain members is required in VMI. Sometimes VMI decisions are delayed and/or the information shared is inaccurate. This research examines the effects of information delay and accuracy, and the sharing of sales and forecast information in a VMI environment facing stationary and nonstationary demand. The simulation experiments show the impact of information delay, information inaccuracy, and information sharing on a variety of performance measures, including inventory levels and fill rates.     

MANAGING VENDOR INVENTORY IN A DUAL LEVEL DISTRIBUTION SYSTEM

Collaborative arrangements among members of the supply chain have received a great deal of interest in recent years as a means of reducing costs. One such arrangement is vendor managed inventory (VMI). VMI allows the vendor to make decisions concerning the quantity and timing of deliveries to the retailer. Such an arrangement offers the potential of a more efficient supply chain by removing the negative effects of retail ordering policies. A thorough review of the literature was conducted to identify factors likely to impact the performance of a VMI partnership. Computer simulation was used to study the effects of these factors from both the vendor's and retailer's perspectives. The results lend insight into the performance of VMI and guidance for managers as to the environments in which VMI is most effective.     

Resilience toward supply disruptions: A stochastic inventory control model with partial backordering under the base stock policy

This paper examines supply-side disruptions using an inventory management framework to gain insights into the economic performance of buyers who use two conventional costing strategies – end-of-cycle and continuous. The proposed model assumes that a single supplier faces full disruptions with a probability, and therefore, fails to procure all the items ordered. Accordingly, the buyer experiences unmet demand, which is assumed to be partially backordered. To make proper replenishment decisions, two base stock (S,T) periodic review optimization models are developed. The objective functions minimize the expected long-run total costs (i.e., ordering, holding, and shortage). After proving their convexity and obtaining the optimal decisions, computational experiments were carried out to investigate the impacts of the change in parameters. The results highlight the importance of selecting a suitable ratio for backorders during supply disruptions, as it leads to lower costs and reduces the inventory obsolescence and overstocking risks. Moreover, the managerial insights derived from this study aid retailers to make better replenishment decisions (in terms of level and frequency) and to be more resilient in times of disruptions. Retailers can benefit from the provided solution algorithm as a computational application.     

Business process innovation in the supply chain – a case study of implementing vendor managed inventory

A growing number of international companies operate in a standard business systems environment. This suggests that standard business system solutions, e.g. from SAP R/3, might be adopted rather than introducing new problem specific systems solutions for new business requirements. This could be a cost efficient alternative in a situation when supply chain sophistication and integration demands from customers are increasing. In the Nordic countries vendor managed inventory (VMI) is an example of a new way of doing business that can give pioneers a competitive edge. The vendor in this case is the first supplier to go into a full-scale VMI relationship with the wholesaler – and has, through this, substantially reduced delivery costs to the retail trade. The case VMI implementation demonstrates that it is possible to arrive at a simple but efficient solution in a standard systems environment. The case shows how VMI can be implemented in a SAP R/3 environment based on the EDIFACT inventory report.     

Optimal and Approximate Policies for Inventory Systems With Order Crossover

A common assumption in inventory analysis is that replenishment orders arrive in the same sequence in which they were placed. In practice, however, a variety of factors may cause orders to arrive out of sequence, a phenomenon known as order crossover. This article analyzes a periodic‐review inventory system for a single item with discrete variable demand and discrete variable and long lead‐times (relative to the review period). Under such a scenario, multiple orders are simultaneously outstanding, and orders may arrive in a different sequence than placed. If such order crossover occurs, traditional inventory analysis overstates expected shortages and standard inventory control policies are no longer optimal. This article discusses why orders may cross over in practice and investigates the implications of order crossover to inventory management policies. We investigate the cost performance of optimal policies under order crossover and also suggest approximate policies which are easier to compute and implement. Both the optimal and approximate policies take advantage of detailed real‐time information about the status of pending orders and goods in transit, and hence in a majority of cases perform better than commonly used policies which do not incorporate such information.     

A COMPARISON OF THE ECONOMIC ORDER QUANTITY AND QUICK RESPONSE INVENTORY REPLENISHMENT METHODS

When determining order quantity, logistics managers can choose between ordering the Economic Order quantity (EOQ) or a Quick Response (QR) quantity. QR is a general term that collectively describes several rapid‐replenishment inventory methods such as Just‐In‐Time or Continuous Replenishment. The QR order quantity is defined as the minimum inventory needed to support operations until the next delivery. The EOQ and the QR methods are substantially different because the EOQ minimizes the joint cost of ordering and holding inventory whereas the QR method minimizes only the cost of holding inventory. The goals of this research are to compare the costs of the two methods and to propose rules that help managers select the more appropriate method to use in specific situations.     

The Minimal Entropy Martingale Measure and the Valuation Problem in Incomplete Markets

Let χ be a family of stochastic processes on a given filtered probability space (Ω, F, (F_t)_t∈T, P) with T?R₊. Under the assumption that the set M_e of equivalent martingale measures for χ is not empty, we give sufficient conditions for the existence of a unique equivalent martingale measure that minimizes the relative entropy, with respect to P, in the class of martingale measures. We then provide the characterization of the density of the minimal entropy martingale measure, which suggests the equivalence between the maximization of expected exponential utility and the minimization of the relative entropy.     

供应商管理库存对供应链收益的影响机理研究

供应商管理库存模式作为一种供应链环境下的库存运作模式,突破了传统的条块分割的库存管理模式,以系统化、集成化的思想实施库存管理,能够提升供应链的整体竞争力。供应商管理库存模式是一种以供应链各环节企业都能实现最低成本为目的,在一个共同协议下由供应商管理库存,不断监督协议执行情况并修正协议内容,使库存管理得以持续改进的合作性策略,具有合作性、互利性、协议性、连续改进性等特点。实施供应商管理库存模式,可以降低零售商和供应链整体的库存成本,增加二者的收益水平。尽管在实施初期,可能会导致供应商库存成本的增加以及收益的减少,但从长期来看,由于供应商对库存的专业化管理以及零售商将更多资源用于商品的市场营销活动之中,可以有效扩大商品的市场销售规模,降低库存管理成本,从而最终提高供应商收益水平。     

VMI在中国的发展与应用——日本近铁国际物流公司实施VMI案例研究

目前,国外许多企业应用VMI已经获得很大的收益,相对而言,国内企业应用VMI还是一个相对较新的课题。文章透过一家第三方物流公司(3PL)——日本近铁国际物流公司实施的VMI为例,阐述VMI管理的思想,分析中国VMI发展现状及障碍。我国企业应根据当前的发展阶段,分析推行VMI的条件是否已完善,并非先进思想就一味引进,而应依靠企业自身特色和优势,采用适当库存管理方法。     

Performance Implications of a Retail Purchasing Network: The Role of Social Capital

This study employs social capital theory to examine how a retail buyer's network of industry peers influences retail performance. We propose that performance is enhanced by three network resources – access, referral, and influence – that result from two structural facets of a retail buyer's network: contact diversity and contact position. We test the model by collecting sociometric data that measures interpersonal ties among 84 retail buyers operating in the same geographic territory in the U.S. golf industry. The results offer evidence that network resources lead to higher levels of performance, even when accounting for differences in human capital and organizational resources. The paper concludes with a discussion of managerial and theoretical implications.     

A Model of Supplier Responses to Just-In-Time Delivery Requirements

When buyers provide incentives for suppliers to deliver just-in-time, suppliers can respond by choosing to hold additional inventory, reducing the variance of flow time to facilitate just-in-time production, or both. A model characterizing the supplier's optimal response to incentives for JIT delivery is presented. The model shows a situation where the optimal action of the supplier is to hold more inventory. When incentives for on-time delivery are increased, the supplier responds by decreasing the variance of flow time and by increasing the lead time allowance. However, the lead time allowance increases more quickly than the variance is reduced, resulting. in a net increase in the amount of inventory that must be held by the supplier. The result is that inventory is pushed upstream. This paper does not suggest that inventory is always pushed upstream in JIT purchasing. Rather, it provides a counter-example to those who presume that holding more inventory is always a non-optimal response to buyer's requests for JIT delivery.     

On the flatness of the transformation surface

Consider an economy equipped with any positive number of primary factors of production and any positive number of first-degree-homogeneous production functions, the inputs of which include produced commodities. Let y be a point in the production surface with n industries active. Then the surface contains an (n?r)-dimensional flat embracing y if and only if at y there are exactly r linearly independent vectors of primary-factor inputs.     

Auction or agent (or both)? A study of moderators of the herding bias in digital auctions

Recent research has shown that buyers in digital auctions are susceptible to the herding bias—gravitation toward listings with existing bids and inconsideration of listings without any bids, manifested in categories of listings that are either coveted or entirely overlooked by buyers. This article investigates two specific types of moderators of herding bias: auction attributes (volume of listing activity, and posting of reservation price) and agent characteristics (seller and bidder experience), and increases our understanding of mechanisms underlying this bias. Practical implications for participants and organizers of digital auctions are discussed, and promising future research opportunities are highlighted.     

THE DOTHAN PRICING MODEL REVISITED

We compute zero‐coupon bond prices in the Dothan model by solving the associated PDE using integral representations of heat kernels and Hartman–Watson distributions. We obtain several integral formulas for the price P(t, T) at time t > 0 of a bond with maturity T > 0 that complete those of the original paper of Dothan, which are shown not to always satisfy the boundary condition P(T, T) = 1 .     

Purchasing veg private labels? A comparison between occasional and regular buyers

Retailers are increasingly extending their private label assortments with meat-substitute, vegetarian and vegan foods (here called veg foods) to respond to emerging consumer trends. However, no studies on consumer buying behavior with regard to veg private labels exist. Accordingly, this work analyses the impact of ethical motives (i.e., environmental, animal welfare, health, and spiritual concerns) and perceptual factors (i.e., trust, perceived quality, and perceived value) as drivers of consumers' buying intentions of regular and occasional buyers of veg private labels, identified by their purchase frequency. The multigroup structural model findings show that occasional buyers are motivated by perceived quality, environmental, and animal concerns, while regular buyers opt for veg private labels on the grounds of their trust in the retailer's own-brand and environmentally-friendly claims. The perceived value is key for both segments.     

Buying Behavior of Western European Food Retailers

Abstract

The aim of this study has been to analyze important aspects of buying behavior of food retailers, i.e., trade buyers' evaluation of product and vendor attributes, based on a number of background variables, when choosing a new supplier of an already well-known product category. The study encompassed the retailers' buying behavior for pork, fish and cheese products. By conducting a conjoint analysis in sixteen Western European countries (15 'old' EU Countries (except Luxemburg), plus Norway and Austria), it is demonstrated that the traditional four Ps are losing ground to some previously neglected attributes, and that it is possible to generalise retailers' buying behavior for different food products across countries, retail organizations, and buyers.     

How buyers frame problems: Revisited

This article investigates the following propositions: a useful approach for building an organizational‐buying–behavior taxonomy might begin with classifying how buyers frame purchasing problems followed by how such frames affect subsequent perceptions and actions in the decision process. Unlike previous taxonomies of buying situations, direct questioning of organizational buyers is used to learn: (1) whether or not they identify different categories of buying problems; (2) if they do, what dimensions they use when framing buying problems; and (3) how do such frames influence their choices of value‐added service alternatives offered by suppliers. To test the propositions empirically, supplier choices are modeled with the use of buying‐decision exercises. A key result of this study is that the buyers’ framing of problems affects their preferences for vendor designs of value‐added customer services. Most likely, the framing of buying problems by organizational buyers is layered and more complex than related taxonomies found in the marketing literature. © 2001 John Wiley & Sons, Inc.     

Managing Critical Spare Parts within a Buyer–Supplier Dyad: Buyer Preferences for Ownership and Placement

Despite the criticality and expense of spare parts, many firms lack a coherent strategy for ensuring needed supply of spare parts. Moreover, scientific research regarding a comprehensive spare parts strategy is sparse in comparison with direct material. Our research identifies and tests three literature-based, theoretically anchored attributes that influence a buyer's preference for inventory ownership and inventory placement when managing the stock of a critical spare part. Our findings indicate that item specificity and item supply uncertainty are useful in predicting a buyer's preference for managing the inventory of a critical spare part. Furthermore, we find that buyers have (1) a strong preference for consignment-based inventory management approaches, (2) a bias against inventory speculation despite its use in practice and analytical models, and (3) a strong preference for inventory postponement when the level of supply uncertainty is low.     

Equilibrium solutions for resource dilemmas

Considered in this article is a class of resource dilemma games designed to study interactive decision behavior in the face of both strategic and environmental uncertainty. Groups of n members are asked to share a common resource pool whose exact size, x, is not known. Rather, x is sampled randomly from a uniform probability distribution which is common knowledge. Each group member j(j=1,...,n) requests r _j units from the random resource pool. Individual decisions are made independently and anonymously. Preplay communication is prohibited. If (r ₁+r ₂+...+r _n ) x, each member j is granted his/her request; otherwise, group members get nothing. We derive the Nash equilibrium solution for this resource dilemma game, and compare it to an expected utility model originally proposed by Suleiman and Rapoport (1988). We then show that the equilibrium solution accounts for the major qualitative features of experimental results reported in two previous studies.     

The Role of Schedule Mismatch in Ending Inventory Decisions in the Presence of Price Cuts

In the high‐tech sector, component suppliers are often able to offer preannounced price cuts (price markdowns) to manufacturers due to technological innovation that allows them to produce the existing components at lower costs. In this context, manufacturers (buyers) are primarily concerned with their existing inventory carried beyond the price cuts in order to lower inventory costs. In this research, we develop a newsvendor‐based decision model for this problem based on our experience in industry and a focal case study environment. Specifically, we consider the issue of delivery and demand uncertainties, and the interplay of the buying firm's operating hours and the transportation carrier's delivery hours, which combine to influence inventory costs and order fulfillment. We illustrate the results with numerical examples and sensitivity analyses, using a real world data set. We found that stockout cost plays a critical role in the ending inventory decisions. Lowering stockout cost will benefit buyers from lower risk of obsolescence costs.