联系向量距离与灰色关联度结合的理想解法

针对传统理想解法采用欧氏距离计算的缺陷,提出了联系向量距离与灰色关联度结合的理想解法.首先将理想点与负理想点均视为确定不确定系统中相互对立的集合,计算各待决策方案与理想解和负理想解的联系向量距离;然后采用灰色关联度方法计算各待决策方案与理想解和负理想解之间的相似程度;其次通过定义新的综合距离和综合距离贴近度构建联系向量距离与灰色关联度结合的理想解法.该方法在有效地解决传统理想解法缺陷的基础上,还包含了待决策方案在趋势上的差异性,同时综合距离在权重分配上充分考虑了决策者的偏好或者专家意见,使评价结果更加有效.最后采用算例验证了该方法的可行性和有效性.     

面向横截面数据的灰色关联度

针对横截面数据的灰色关联度分析问题,研究了常用灰色关联度在横截面数据的适用性.提出具有放射变换保序性的灰色距离关联度,实例说明距离关联度的实用性与有效性.将灰色距离关联度推广到系统因素为矩阵的矩阵范数关联度,且在多属性群决策问题的成功应用证明了其合理性.     

基于灰色局势决策的采煤工艺评价与选择

采煤工艺的评价与选择是一个多目标规划,煤矿生产条件具有复杂性,地下工程具有信息不完备性,为避免受到人为主观因素的影响,能够对采煤工艺的选择提供客观评价的依据,采用灰色局势决策的方法,建立多目标综合决策矩阵,计算综合效果测度进行决策,评价结果与模糊综合评价法、灰色聚类法和灰色关联分析法相比较基本一致,灰色局势决策的方法较传统方法更精确,更有效,该方法在决策矿业工程中信息不完备问题时,具有一定的参考价值和指导意义.     

基于11种灰色关联度法的卫生指标序列应用比较分析

以序列灰色关联分析方法应用为视角,简述多种关联度方法基本流程;借助算例验证分析,为类似问题研究提供技术参考.分别阐述11种灰色关联度法原理及步骤,以医疗卫生指标时间序列为例计算实现.简要给出所有方法实施步骤,方法原理及信息利用有差异.序列间关联度结果与实际问题演示情形一致.11种灰色关联度法有集成讨论意义,有待于卫生领域综合对比及科学选用,也可以为因素筛选、综合评价、时序分析和聚类优化等应用问题提供借鉴.     

基于修正邓氏灰色关联度的设备费用影响因素分析

针对武器装备数据多为小样本情况,采用灰色关联度对其研制生产费用影响因素的确定,针对灰色关联度不能处理负相关和组合相关的问题,提出应用普通相关和逐步回归对灰色关联度结果进行修正,实例分析表明处理结果更符合实际情况.     

基于区间灰数多属性群决策建模技术的卫生应急综合评价研究

多属性灰色群决策建模方案设计为立足点,引入区间灰数、相离度、逼近理想点、群决策集结算法知识,在属性权重为实数、区间灰数或优化运算形式下,经属性值规范化后制定理想方案.首先,计算区间灰数相离度、灰色关联系数、灰色关联度,讨论以理想方案贴近度确定排序或择优.然后,改进为群体专家独立决策环境下,由属性矩阵虚构理想方案并计算关联度、贴近度,与专家权重集结为贴近度矩阵,由逼近理想点思路排序及择优.最后,由疾控机构卫生应急能力评价案例验证可行性,区间灰数、属性测度、专家权重以及属性群决策信息利用充分,这套建模方案对于类似问题也有推介意义.     

三角模糊数型多属性决策灰色优化模型及其在工程设计方案评价中的应用

工程设计方案评价时由于掌握的信息不充分,资料不全,加之问题本身的复杂性、不确定性以及人类思维的模糊性,方案的评价值往往难以精确表达,常用三角模糊数形式表示.针对基于"理想方案"的灰色关联分析评价存在的不足,根据灰色关联度定义,运用扩展的最小二乘方准则构造目标函数,建立了三角模糊数型多属性决策灰色优化模型.模型同时考虑了"理想方案"和"负理想方案",克服了仅考虑一种方案时排序的不相容问题,更具有客观性和合理性.应用实例表明,该模型概念清晰,数学推导严谨,评价值分辨率高,评价结果与实际相符.     

优化矿井通风系统方案的灰色关联模型

考虑到在矿井通风系统方案的评价中其众多的技术经济指标所具有的不同属性 ,根据灰色系统理论关联度原理 ,将灰色关联度多层次分析方法应用于矿井通风系统方案的优化 ,为矿井通风方案优选提供了一种科学的方法 ,进而拓宽了灰色关联度分析的应用领域 .     

灰色模糊聚类理论在飞机方案优选中的应用研究

将灰色系统理论应用到飞机设计方案评价中,研究了一种含有方案评价指标体系和考虑评价指标权重以及灰关联分析的飞机方案优选灰色模糊聚类决策理论,这种决策理论利用指标权重将评价指标联系在一起,在评价方案与理想方案灰关联度的基础上进行灰色模糊聚类,实现方案优选.最后以一个短距/垂直起降(V/STOL)飞机设计实例证实此方法的科学性与可行性.     

基于有序梯形模糊灰色关联TOPSIS的多属性决策方法

研究了有序梯形模糊数来表示不确定语言环境下的灰色关联TOPSIS多属性决策问题。首先应用有序梯形模糊数标度方案属性偏好信息,在传统梯形模糊数基础上增加了一个方向属性,使得决策信息的表示更加细腻;提出了有序梯形模糊环境下多属性决策灰色关联TOPSIS综合优选算法,引入了距离和灰色关联度相结合的综合贴近度公式,实现最优方案与理想方案的位置与曲线形状的一致性;最后通过制造系统内流动控制实例说明了所提出有序梯形模糊灰色关联TOPSIS方法的可行性和有效性。     

Separable programming/duality approach to solving the multi-product Newsboy/Gardener Problem with linear constraints

The Gardener Problem is an extension of the multi-product Newsboy Problem with constraints. It deals with situations where not only the demand is random but also the yield (the supply). Separable programming and duality approaches are utilized to solve the constrained Newsboy/Gardener Problem. The solution methodologies are developed for the common probability distribution functions for the demand, and uniform distribution for the supply, rendering exact and approximate solutions to the problem. Numerical examples are given and when applicable, the performance of the developed approach is compared to those of existing works in this arena. The results reveal that the developed solution methods efficiently converge to the optimal or near optimum solutions. Also, a salient feature of the proposed methodologies is that they can utilize readily available commercial software to solve the considered problems. This feature facilitates the portability of the developed models to the classroom environment.     

Optimal pricing and inventory policies: Centralized and decentralized decision making

The paper studies an optimal control problem of pricing and inventory replenishment in a system with serial inventories. Consumer demand for a specific product at a retail outlet depends on price as well as the in-store stock of the product. The hypothesis is that for certain consumer products, a large volume of displayed goods leads consumers to buy more than if the stock is small. In addition to the stock that is on display in the store, there is an inventory of the product in a central warehouse. First we consider a setup in which management of the two stocks is decentralized such that pricing decisions are made by the store manager who also decides on the level of in-store inventory. The warehouse manager makes the replenishment decisions concerning the stock in the warehouse. Next we study the problem where stock management and pricing decisions are centralized. Optimal trajectories for inventories, replenishment rates, and retail price are derived by using phase diagrams and a formal synthesizing procedure.     

基于EGARCH模型的分类商品零售价格波动的信息效应研究

利用EGARCH模型对我国部分具有代表性的分类商品零售价格波动的信息效应进行了实证分析.分析结果显示,我国分类商品零售价格波动特征是不同的.在六个具有代表性的分类商品零售价格指数中,有四个指数的方差具有时变性特征.在四个当中,有三个指数有非对称信息效应,即非期望的价格上涨或下降信息对价格波动的影响是非对称的.另外的两个价格指数的方差为常数,价格波动稳定.     

A critical comparison of the various plausible inter-echelon gaming processes in supply chain models

An increasing number of supply-chain models are related to the following structure: (i) a manufacturer supplies a product to a retailer—who fixes a retail price and then retails the product to the consumers; (ii) the effect of the retail price on sales volume is dictated by a deterministic demand curve known to both parties. Results from these models depend very much on the ‘gaming process’ that is assumed to govern how the manufacturer and the retailer interact with each other. This paper reviews and compares some basic characteristics of seven seemingly plausible gaming processes; including the two most common ones: the manufacturer-Stackelberg and the fixed-markup-retailer processes. Our results show that: (i) each of the seven processes appear to be no less plausible than the other six; (ii) all seven processes possess some implausible characteristics; (iii) the relationships among the processes are confusing and do not appear to be intuitively logical; (iv) the relationships among these processes are further complicated by the way they are affected by the form of the assumed demand curve. Our results show that in supply-chain modelling more attention should be given to: (i) the proper selection of an appropriate gaming process assumption; (ii) how the model's results change under different gaming processes; (iii) the incorporation of information asymmetry that will allow these gaming-process assumptions to become more realistic.     

Some properties of buyback and other related schemes in a newsvendor-product supply chain with price-sensitive demand

A manufacturer wholesaling to a retailer a ‘newsvendor-type’ product such as a seasonal/fashion good or a perishable food item is considered here. It is known that such a manufacturer/retailer channel has difficulties in fully realizing the market's profit potential. We study a theoretical construct of such a channel and present practically useful results for a manufacturer trying to design more profitable pricing schemes. Specifically, we consider a ‘dominant’ manufacturer supplying a newsvendor-type product to a retailer. The retail market volume varies with the unit retail price according to a stochastic demand curve. We study the design and performance of ‘price-only’, ‘buyback’ and ‘manufacturer-imposed retail price’ schemes. All these schemes have been considered in earlier works. The first part of this paper studies some important but previously overlooked aspects of price-only and buyback schemes. We show that the performance of these schemes is strongly and somewhat counter-intuitively affected by the specific form of demand curve and of demand randomization. Thus, we identify hitherto neglected factors that must be carefully considered when designing pricing schemes for actual implementation. The second part of this paper demonstrates the practicality and merit of using buyback in conjunction with a manufacturer-imposed retail price—an arrangement overlooked in the literature because it is widely mistaken as illegal. Overall, the paper shows how a manufacturer can better realize the market's potential by: (i) modifying slightly the well-known buyback arrangement; and (ii) carefully modelling certain hitherto neglected aspects of the price/demand relationship—a conclusion quite contrary to what one might surmise from the current theoretical literature.     

Retail price markup commitment in decentralized supply chains

We investigate the operational decisions and resulting profits for a supply chain facing price-dependent demand under a policy where there is an ex-ante commitment made on the retail price markup. We obtain closed-form solutions for this policy under the assumption of a multiplicative demand function and we analytically compare its performance with that of a traditional price-only policy. We compare these results to results obtained when demand follows a linear additive form. These formulations are shown to be qualitatively different as the manufacturer’s wholesale pricing decision is independent of the retail price markup commitment in the multiplicative case, but not when demand is linear additive. We demonstrate that the ex-ante commitment can lead to Pareto-improving solutions under linear additive demand, but not under the multiplicative demand function. We also consider the effect of pricing power in the supply chain by varying who determines the retail price markup.     

Using MSRP to enhance the ability of rebates to control distribution channels

Manufacturers have increasingly instituted widespread mail-in rebate programs in recent years. Two primary purposes for rebates are to: (1) more directly impact consumer demand by reducing net retail price, and (2) capitalize on consumers’ slippage behavior because not all consumers who intend to redeem the rebate at purchase time end up actually redeeming it. However, retailers can counteract the power of rebates to impact demand by simply raising the retail price by the amount of the manufacturer’s rebate. We show that by combining a manufacturer’s suggested retail price (MSRP) along with a rebate, the manufacturer can better control the channel by inhibiting the retailer’s ability to raise price, particularly when consumers exhibit loss aversion. As a result, incorporating MSRP with a rebate promotion plan increases the manufacturer’s profit. More surprisingly, the profit of the supply chain as a whole also increases, and the channel efficiency increases as well. In fact, contrary to results from the existing rebate literature suggesting that rebates should always be offered whenever slippage exists, we demonstrate that MSRP can actually be a more effective tool than rebates in managing retailer and consumer behavior when consumers do not have sufficient loss aversion and the slippage rate is low enough.     

制造商竞争环境下逆向供应链的政府奖惩机制研究

主要运用博弈论方法探讨制造商竞争环境下的逆向供应链奖惩机制,建立了5个决策模型,分别是逆向供应链集中式决策、以逆向供应链和不回收再制造的制造商的总利润为目标决策、逆向供应链分散式决策、政府对制造商实施奖惩机制以及政府对回收商实施奖惩机制下逆向供应链的决策模型。研究表明:竞争对回收率提高有益,竞争越激烈回收率越高;积极回收再制造的制造商的新产品零售价较低,具有价格竞争优势;奖惩制造商和奖惩回收商均能起到提高回收率的作用,奖惩力度越大,回收率越高,新产品零售价越低;奖惩制造商比奖惩回收商更能调动制造商和回收商的积极性;奖惩制造商时的回购价高于奖惩回收商时的回购价;在实施奖惩机制时,回收再制造的制造商利润高于不回收再制造的制造商的利润;不回收再制造的制造商的利润随奖惩力度的增大而降低。     

A fractional programming approach for retail category price optimization

We present a new mixed-integer programming (MIP) approach to study certain retail category pricing problems that arise in practice. The motivation for this research arises from the need to design innovative analytic retail optimization techniques at Oracle Corporation to not only predict the empirical effect of price changes on the overall sales and revenue of a category, but also to prescribe optimal dynamic pricing recommendations across a category or demand group. A multinomial logit nonlinear optimization model is developed, which is recast as a discrete, nonlinear fractional program (DNFP). The DNFP model employs a bi-level, predictive modeling framework to manage the empirical effects of price elasticity and competition on sales and revenue, and to maximize the gross-margin of the demand group, while satisfying certain practical side-constraints. This model is then transformed by using the Reformulation–Linearization Technique in tandem with a sequential bound-tightening scheme to recover an MIP formulation having a relatively tight underlying linear programming relaxation, which can be effectively solved by any commercial optimization software package. We present sample computational results using randomly generated instances of DNFP having different constraint settings and price range restrictions that are representative of common business requirements, and analyze the empirical effects of certain key modeling parameters. Our results indicate that the proposed retail price optimization methodology can be effectively deployed within practical retail category management applications for solving DNFP instances that typically occur in practice.     

Green product development under competition: A study of the fashion apparel industry

Motivated by the observed industrial issues, we analytically develop a fashion supply chain consisting of one manufacturer and two competing retailers and investigate how retail competition and consumer returns affect green product development in fashion apparel. In the basic model, that is, the pure “product greenness level” game, we find that the optimal greenness level of the fashion product decreases along with the level of market competition. This finding implies that a more competitive market leads to a lower optimal greenness level. We also identify that when the consumer return rate increases, the optimal product greenness level is substantially reduced. In the extended model with joint decisions on greenness and pricing, we find that the optimal product greenness level for the whole channel is always higher in the scenario when both retailers charge a higher retail price than in the case with a lower retail price. As such, the underdevelopment of green fashion products is a result of fashion industry features, such as an extremely competitive environment for green product development, relatively low retail prices for fashion products, and high consumer return rates. Therefore, fashion companies should join a co-opetition game for the green product market and simultaneously enhance their efficiency in managing consumer returns. To support our analytical findings, we conduct extensive industrial interviews with various representative companies. Based on this multi-methodological approach (MMA), this paper generates practice-relevant managerial insights that not only contribute to the literature, but also act as valuable references for industrialists.