Interorganizational Determinants of Environmental Purchasing: Initial Evidence from the Consumer Products Industries*

Environmental purchasing consists of the purchasing function's involvement in activities that include reduction, recycling, reuse, and substitution of materials. Despite the potentially important role that the purchasing function can play in a firm's environmental activities, little research has been performed to date that examines the factors that impact environmental purchasing. The authors develop and empirically test a theoretical model that examines how interorganizational factors both drive and constrain purchasing's involvement in environmental activities. The empirical findings suggest that environmental purchasing activities will be facilitated through increased coordination with suppliers as well as downstream members of the supply chain, including retailers. The results also suggest the need for increased coordination within the firm, particularly between the purchasing function on the inbound side and marketing and distribution functions on the outbound side.     

Reconfiguring the Supply Network Using Current Performance Data

Reconfiguration of the supply chain network from time to time is essential for businesses to retain their competitive edge. This paper presents a methodology for reconfiguration of an existing supply chain network. The methodology is characterized by two decision levels. In the first level, the current network performance is evaluated and efficient practices are identified. In the next level, a model that incorporates efficient practices is developed to reconfigure the network. This integrated methodology allows for decision maker (DM) input throughout the process. The methodology has been implemented and tested in the reconfiguration of an outbound petroleum supply chain network for CountryMark Cooperative, Inc. In this case study, Data Envelopment Analysis (DEA) is used to analyze current operations and an integer programming (IP) model that incorporates efficiency metrics is developed for selection of distribution facilities and allocation of resources to the facilities. Use of this methodology can lead to improved operations and reduced operating expenses.     

Optimal Policy for a Reseller When the Supplier Offers a Temporary Reduction in Price*

A common practice in product distribution is the case in which the supplier offers a temporary reduction in price. It is suggested in the literature that in such situations, the reseller may engage in forward buying (i.e., purchasing additional stock at the reduced price offered by the supplier for later sale at the regular selling price). In this paper, a model is formulated of the reseller's response when the supplier offers a temporary reduction in price. It is assumed that the market demand for the product is elastic with respect to the selling price the reseller sets. A procedure for determining the optimal response of the reseller is developed. The model presented in this paper can easily be adapted to the case in which the reseller faces a permanent increase in the price charged by the supplier.     

Effects of some design factors on the distribution of similarity indices in cluster analysis

This article investigates the effects of number of clusters, cluster size, and correction for chance agreement on the distribution of two similarity indices, namely, Jaccard and Rand indices. Skewness and kurtosis are calculated for the two indices and their corrected forms then compared with those of the normal distribution. Three clustering algorithms are implemented: complete linkage, Ward, and K-means. Data were randomly generated from bivariate normal distributions with specified means and variance covariance matrices. Three-way ANOVA is performed to assess the significance of the design factors using skewness and kurtosis of the indices as responses. Test statistics for testing skewness and kurtosis and observed power are calculated. Simulation results showed that independent of the clustering algorithms or the similarity indices used, the interaction effect cluster size x number of clusters and the main effects of cluster size and number of clusters were found always significant for skewness and kurtosis. The three way interaction of cluster size x correction x number of clusters was significant for skewness of Rand and Jaccard indices using all clustering algorithms, but was not significant using Ward's method for both Rand and Jaccard indices, while significant for Jaccard only using complete linkage and K-means algorithms. The correction for chance agreement was significant for skewness and kurtosis using Rand and Jaccard indices when complete linkage method is used. Hence, such design factors must be taken into consideration when studying distribution of such indices.     

中国服务业的新经济地理特征

 利用2008年地级及以上城市层面服务业的汇总数据和2007年的城市数据,本文对影响服务业产业集聚的因素作了初步的考察,特别关注代表地区市场容量及与市场接近程度的城市市场潜能带来的影响。我们的分析表明,市场潜能较高的城市其服务业集聚程度也更高,平均来看,城市市场潜能提高1%,其服务业集聚程度提高0.2%左右。并且市场潜能对服务业集聚的影响在中部地区最为明显,东部地区次之,西部地区则不显著。市场潜能对服务业影响在地区间的差异可能与东部、中部、西部地区在城市体系以及地理位置的不同有关。本文还分析了其他城市特征及行业差异对服务业分布的影响。     

促进加工贸易向西部地区转移政策研究

为缩小地区经济差距,改变我国加工贸易东重西轻的分布格局,同时也为了加工贸易转型升级战略的顺利实施,促进加工贸易向西部地区转移具有十分重要的现实意义。本文从政策视角着重论述我国西部地区加工贸易的现状和承接加工贸易的优势,进而分析影响西部地区承接加工贸易的制约因素,提出促进加工贸易向西部地区转移的政策建议。     

基于尾部指数回归方法的CVaR估计以及实证研究

 在险价值VaR是一种非常重要的金融风险度量方法,近期也有很多关于动态VaR以及条件VaR (CVaR) 等方面的研究。根据金融资产的收益率具有重尾特征这一事实,本文假定金融资产收益率服从重尾分布,并假定重尾分布的尾部指数随着收益率发生变化。本文基于尾部指数回归模型对重尾分布的尾部指数进行估计,进而得到收益率尾部数据所服从的条件分布,并首次运用该方法对条件VaR进行估计。本文对沪深300指数进行了实证研究,得到CVaR的估计,并对估计得到的CVaR的预测效果作出检验,并与传统VaR估计方法进行了对比,实证结果发现本文的方法的预测效果更好。     

Some robustness issues for comparing multiple logistic regression slopes to a control for small samples

For comparing several logistic regression slopes to that of a control for small sample sizes, Dasgupta et al. (2001) proposed an "asymptotic" small-sample test and a "pivoted" version of that test statistic. Their results show both methods perform well in terms of Type I error control and marginal power when the response is related to the explanatory variable via a logistic regression model. This study finds, via Monte Carlo simulations, that when the underlying relationship is probit, complementary log-log, linear, or even non-monotonic, the "asymptotic" and the "pivoted" small-sample methods perform fairly well in terms of Type I error control and marginal power. Unlike their large sample competitors, they are generally robust to departures from the logistic regression model.     

Coverage probabilities of nonparametric simultaneous confidence bands for a survival function

Simultaneous confidence bands provide a useful adjunct to the popular Kaplan–Meier product limit estimator for a survival function, particularly when results are displayed graphically. They allow an assessment of the magnitude of sampling errors and provide a graphical view of a formal goodness-of-fit test. In this paper we evaluate a modified version of Nair's (1981) simultaneous confidence bands. The modification is based on a logistic transformation of the Kaplan–Meier estimator. We show that the modified bands have some important practical advantages.     

邓小平收入分配理论在微观企业的实现机制

邓小平收入分配理论涉及收入分配要素、收入分配原则、收入分配目标及实现路径等问题。邓小平收入分配理论是我们收入分配实践的重要理论依据。企业是国民经济的基本单位。通过对邓小平收入分配理论的简单介绍,从三个方面分析了邓小平收入分配理论在微观企业的实现机制,以期对企业的收入分配机制设计有所裨益。