An inventory reservation problem with nesting and fill rate-based performance measures

In many inventory settings companies wish to provide customer-differentiated service levels. These may, for example, be motivated by differences in the perceived customer lifetime value or by specific contractual agreements. One approach to provide differentiated service levels is to reserve some portion of the available inventory exclusively for specific customer classes. Existing approaches to inventory reservation are typically based on the assumption that a company can assign a customer specific revenue or penalty cost to any order or unit of demand filled or unfulfilled. In practice, however, it is usually extremely difficult to accurately estimate (especially long term) monetary implications of meeting or not meeting customer demand and corresponding service level requirements. The research presented in this paper addresses the problem of setting appropriate inventory reservations for different customer classes based on fill rate-based performance measures. We model a single period inventory reservation problem with two customer classes and nesting. We develop exact expressions for two conflicting performance measures: (1) the expected fill rate of high priority customers and (2) the expected loss in the system fill rate induced by inventory reservation. With these expressions a decision maker can analyze the tradeoff between the loss in overall system performance and the higher expected fill rates for prioritized customers. We provide analytical insights into the effects of nesting and the impact of relevant problem parameters on these two performance measures. The analytical insights are illustrated and highlighted through a set of numerical examples. Although we limit our analysis to a single period inventory reservation problem, we expect that our results can be utilized in a wide range of problem settings in which a decision maker has to ration a perishable resource among different classes of customers.     

Product Differentiation in the Spanish Beef Industry

Abstract

This paper aims to investigate changes in the structure of the Spanish quality beef industry in response to the significant decline in beef consumption happened over the last few decades. The role of product differentiation, mechanisms and factors involved in it, are specially studied. We use focus groups and a survey to examine the outlook for the organization of the beef industry, and trends in the development of product differentiation mechanisms and vertical co-ordination strategies.

Results reveal the existence of a restructuring process that is being implemented in two ways: Protected Geographical Indications (PGI) and Quality Certified Brands (QCB). Each strategy forms its own entry barriers: the origin of calves in the case of PGI and farm size in QCB; they are therefore complementary rather than competitive.     

东北老工业基地大城市社会空间的问题及治理

立足于东北老工业基地的宏观视角,分析了大城市社会空间发展演化的主要特征,并对当前社会空间发展存在的问题进行了深刻的剖析,从重构途径、政府职能、城市规划等角度,提出了治理大城市社会空间的对策。     

广西城乡居民信息消费分化影响因素研究

根据消费理论及信息消费的特点,城乡居民信息消费分化是多因素综合作用的结果。5变量SVAR(2)模型的实证结果进一步表明收入分化和文化素质分化是信息消费分化最重要的两个内在影响因素,其贡献率分别为29%和28%;紧随其后的消费氛围分化与消费条件分化是不容忽视的外在因素,贡献率分别为20%和18%。显然,降低这些影响因素的分化程度是有效缓解城乡信息消费分化的关键。     

Differentiation of the Peasantry Under Feudalism and the Transition to Capitalism: In Defence of Rodney Hilton

The focus of the essay is one specific theme pursued by Rodney Hilton: that of differentiation of the English feudal peasantry and the implications this had for the development of capitalism in England. His contribution on this, along with those of E. A. Kosminsky and of Maurice Dobb, are considered and are contrasted with the view of Robert Brenner. For Brenner peasant differentiation has no causal importance: it is an outcome of transformation and not a driving force in its securing. For Hilton, it is central to transformation: it is not an outcome but a determining variable, a causa causans rather than a causa causata. The Brenner position, it is argued, is incomplete in its ignoring of peasant differentiation in feudal England. It was one of Hilton's accomplishments to explore this in scholarly detail, and with analytical precision. It is suggested that if this is abstracted from an adequate examination of the transition to capitalism in England cannot proceed.     

东部地区产业结构调整的新特点与启示

当前我国东部地区正在进行的新一轮产业结构调整,表现出二、三产业并重、产业结构迅速知识化、产业间分工与产业内分工并举等诸多崭新的特点,可以为中、西部地区承接产业转移和提高产业竞争力提供有益的启示。     

The option of joint purchase in vertically differentiated markets

Summary. Within the framework proposed by Mussa and Rosen (1978) for modelling quality differentiation, consumers are assumed to make mutually exclusive purchases. A unique pure strategy equilibrium exists in this case. In this note, we allow consumers to buy simultaneously different variants of the differentiated good. We call this the “joint purchase option”. The paper proposes a detailed analysis of price competition when this option is opened: first, we show that either uniqueness, or multiplicity, or absence of price equilibrium arise, depending on the utility derived from joint purchase relative to exclusive purchase. Second, we characterize these equilibria, whenever they exist. Received: July 25, 2001; revised version: October 21, 2002 RID="*" ID="*" The second author gratefully acknowledges the financial support from Interuniversity Attraction Pole Program- Belgian State- Federal Office for Scientific, Technical and Cultural Affairs under contract PAI 5/26. Correspondence to: X.Y. Wauthy     

Deregulation and environmental differentiation in the electric utility industry

This paper analyzes how economic deregulation impacts firm strategies and environmental quality in the electric utility industry. We find evidence that the deregulation introduced to this historically staid industry has stimulated environmental differentiation. Differentiation is most likely to appear where its point of uniqueness is valued by customers, and we confirm this relationship in our sample. Specifically, utilities that served customers who exhibited higher levels of environmental sensitivity generated more ‘green’ power. The tendency for firms to differentiate in this way is lessened if they are relatively more dependent on coal‐fired generation or relatively more efficient. Thus, there is evidence that firms sort themselves into either differentiation or low‐cost strategies as the competitive realities of a deregulated world unfold. Deregulation and the ensuing environmental differentiation illustrate how utilities exploited formerly unmet customer demand for green power. The result has been greater levels of renewable generation and, hence, a cleaner environment. Copyright © 2007 John Wiley & Sons, Ltd.     

后危机时代海外共同基金业的发展

共同基金作为历史悠久、运作规范的主流投资品种,在资产管理行业中具有举足轻重的地位。在次贷危机对全球金融业产生严重冲击的背景下,全球共同基金业也未能独善其身。但随着危机热浪退去,海外共同基金业又重新显示出旺盛的生命力。本文梳理了2009年以来海外共同基金的发展状况,从规模、类型、申购、费率、交易自动化等多个角度进行深入分析,从而得出共同基金产业后危机时代呈现出的一些新特点,及其与全球金融市场之间的联动与契合。