Using the Pack‐and‐a‐Half Rule to Eliminate Backroom Inventories in Retail Operations

In the retail industry, backroom inventories are typically associated with higher labor costs and greater operational complexity. Thus, retailers look for ways to eliminate backroom inventories. A heuristic used for this purpose is the pack‐and‐a‐half rule which suggests that the shelf space allocated for a product should be at least 50% larger than the case pack quantity in which the product is delivered. Despite its popularity among retailers, the pack‐and‐a‐half rule has been ignored in the academic literature. We introduce the pack‐and‐a‐half rule, assess its impact on a retailer's profits, identify cost, demand, and product characteristics driving this impact, and propose a modification. Based on an analysis of data obtained from a retailer on 1,986 SKUs in 20 categories, we find that the pack‐and‐a‐half rule decreases a retailer's profits, on average, by 10% when applied uniformly across all SKUs. Further, this decrease is significantly affected by product depth, product width, demand elasticity, case pack quantity, and inventory carrying cost. Finally, we develop a set of modifications based on these variables where the pack‐and‐a‐half rule is applied selectively and in a stepwise fashion. These modifications limit the decrease in a retailer's profits to a range between 6% and 7%.     

辐射迁移方程--一个K-辛空间上的正则方程

说明了均匀、轴对称、无源介质是一个K-辛空间上的Hamilton系统，Hamilton函数是系统的守恒量；数值计算辐射强度角分布的合理途径是将辐射迁移方程离散成以离散Hamilton函数为守恒量的有限维K-辛空间上的正则方程，并采用保离散Hamilton函数守恒的K-辛算法数值求解．     

试论生态林业系统的时空观

生态林业系统具有时间、空间两个序列的开发前景。长周期,大跨度的生态林业生产可以分解为复合的短周期方式,使生态意识与经济效益有机结合。空间组合的多层次立体开发有效地利用了光、热、水、土资源,并获得最大生物量;地域组合着眼宏观,注重研究大型骨干及网络性生态工程问题。     

On the test of the correction mechanism for mis-pricing between assets using a statistical yield spread model

This paper investigates the existence of a correction mechanism for mis-pricing between Japanese stock and bond. By this correction mechanism we mean that when deviations occur from the equilibrium levels of the expected return differentials between stock and bond — the risk premium differentials, the market will tend to correct the mis-pricing and bring the expected return differentials back to the equilibrium levels. We assume that the yield spread between the predicted earnings price ratio of stock and the yield to maturity of bond reflects the risk premium between stock and bond, and estimate the equilibrium risk premium differentials and mis-prices between stock and bond by modelling their behaviors with a statistical yield spread model (SYS). Empirical results strongly indicate the existence of the mis-pricing correction mechanism, suggesting the inefficiency of securities markets.     

中石化上游领域竞争力和抗风险能力的定量分析

在分析石油公司上游领域竞争力影响因素的基础上，提出了定量评价上游 领域竞争力和抗油价风险能力的定量评价方法，按上游综合竞争力指标将世界石油公司分为三类，第一类公司的指标值均在90以上，第二类公司在55－70，第三类公司在25－35。分析表明中石化集团上游领域竞争力较低，承受体油价的时间很短，但是，中石化集团公司上游竞争力和抗风险能力有很大的改善余地，并提出提高竞争力和抗风险能力的措施和建议。     

Equilibria in large economies with a separable Banach commodity space and non-ordered preferences

The purpose of this paper is to provide an existence result of equilibria for economies with a measure space of agents, a non-trivial production sector and an infinite dimensional commodity space. The commodity space is modeled by an ordered separable Banach space whose positive cone has a non-empty interior. The discretization approach proposed in this paper, allows us to extend the existence results in Khan and Yannelis [Equilibrium in markets with a continuum of agents and commodities. In: Khan, M.A., Yannelis, N.C. (Eds.), Equilibrium Theory in Infinite Dimensional Spaces. Springer, Berlin, 1991] and Podczeck [Economic Theory 9 (1997) 585] to economies with a non-trivial production sector and with possibly non-ordered but convex preferences as well as partially ordered (possibly incomplete) but non-convex preferences.     

Research on the Present Situation and Countermeasure of the Development of Chinese Architectural Industry

Along with the development of Chinese social economy and the innovation of government policy, Chinese Architectural Industry is playing a more and more vital role in the entire national economy. This paper first abstracts the connotation and basic characteristic of the Architectural Industry, then discusses the present situation of the development of Chinese Architectural Industry and carries on the analysis on the entire construction industry. Finally discusses the development tendency of Chinese architectural industry, and put forward the corresponding policy proposals to its developmental strategy.     

"转化"理论在马克思劳动价值论中的地位及其局限

本文认为,马克思的劳动价值论是以“简单商品经济”为基础构建起来的,“转化”理论是马克思劳动价值理论由“简单商品经济”通向资本主义现存生产方式的桥梁,它使马克思劳动价值论不再仅仅局限于“简单商品经济”的范围,而是其全部理论的支点。然而它在马克思的劳动价值理论中并非是一种完全自洽的存在,它在解释资本主义社会现实经济活动方面,本身也存在一些局限,留下了一些值得思考的问题。     

Flexibility at different stages in the life cycle of projects: An empirical illustration of the “freedom to maneuver”

Many textbooks on project management present illustrations concerning the relative size of project attributes during different project phases. The derived models all have attributes in common, such as uncertainty, significance of decisions, and degree of freedom to maneuver, that are typically high in the beginning of the project and low in the end. At the same time, variables such as the accumulated cost and available information begin at low levels and end up at a high level at the end of the project. Based on empirical data from projects, this paper illustrates and quantifies one of these attributes, the freedom to maneuver, in different project phases.