存货管理的第四次变革——供应链管理

存货管理经历了三次历史性变革，但还是无法消除整条产业链上的库存，针对这一顽症，供应链管理应运而生，并成功通过了理论界和实践界的双向考验，促进了存货管理的第四次变革。     

Empirical Bayes analysis of log-linear models for a generalized finite stationary Markov chain

This article presents the empirical Bayes method for estimation of the transition probabilities of a generalized finite stationary Markov chain whose ith state is a multi-way contingency table. We use a log-linear model to describe the relationship between factors in each state. The prior knowledge about the main effects and interactions will be described by a conjugate prior. Following the Bayesian paradigm, the Bayes and empirical Bayes estimators relative to various loss functions are obtained. These procedures are illustrated by a real example. Finally, asymptotic normality of the empirical Bayes estimators are established.     

Testing time-homogeneity of rating transitions after origination of debt

When modelling rating transitions as continuous-time Markov processes, in practice, time-homogeneity is a common assumption, yet restrictive, in order to reduce the complexity of the model. This paper investigates whether rating transition probabilities change after the origination of debt. Accordingly, we develop a likelihood-ratio test for the hypothesis of time-homogeneity. The alternative is a step function of transition intensities. The test rejects time-homogeneity for rating transitions observed over 7 years in a real corporate portfolio. Especially 1-year transition probabilities increase over the first year after origination. This time effect suggests that banks should manage their credit portfolios with respect to the age of debt.      

单位运输成本变化的供应链模型分析

在需求信息不确定情况下，由一个供应商和一个经销商构成两级供应链系统，考虑谊系统在商品边际运输费用随订货量增加而递减的情况，分析经销商采集需求不确定信息的必要备件，指出供销双方共享需求不确定信息的条件，以厦供应链系统中多个经销商联合订货的优势。     

现代物流服务企业价值链的分析与构建

文章分析了现代物流服务企业所具有的服务企业和制造企业的双重特点,剖析了在现代物流服务企业价值链分析中运用基本价值链模型和服务价值链模型可能存在的局限性,在此基础上探讨了现代物流服务企业价值链模型的构建。     

Testing for negativity in a demand system: A Bayesian approach

The paper introduces Bayesian inference into a demand model. This allows us to test for the negativity condition of the substitution matrix which is difficult to handle directly in the traditional approach. To illustrate the Bayesian inference procedures, we estimate the Rotterdam model and test the demand properties using Japanese data. The empirical results show the importance of specifically considering negativity in demand analysis. First version received: September 1997/final version received: February 1998     

连锁经营的电子商务经营模式探析

连锁经营作为一种商业组织和经营形式,被称为“现代流通的革命”,随着信息化的不断推进,电子商务的发展使得连锁经营的盈利模式发生了改变。本文通过对连锁经营和电子商务的分析,指出电子商务和连锁经营互动发展模式,进而阐述了我国连锁企业与电子商务互动发展模式的选择。     

Do rice prices follow a random walk? Evidence from Markov switching unit root tests for Asian markets

This study revisits the issue of mean reversion in the import rice prices of six Asian countries over the period between 1995 and 2015. Augmented Dickey Fuller tests with a conventional linear regression model support the presence of a unit root in the levels of the price data. However, when regressions allow for Markov switching in coefficients and variances to capture periodic shifts in levels and volatilities, there is strong evidence against the unit‐root null hypothesis in favor of stationarity over much of the observation period.     

中国省际城镇职工工资收入分布演进的时空特征

运用Kernel密度估计方法和空间马尔科夫链分析方法,并将空间因素纳入分析框架中,对1978—2009年期间中国省际城镇职工工资收入分布演进的时空特征进行了分析。研究结果表明:从时间动态性看,中国省际城镇职工工资收入的差距正逐步固化和深化,多俱乐部收敛特征明显、贫困陷阱问题日益突出;从空间动态性看,近邻效应对省际城镇职工工资收入分布演进存在一定影响,多数省份的工资收入水平向邻区的平均工资收入水平演进。     

创新价值链视角下的区域创新活动收敛分析

基于创新价值链视角,将我国创新活动分为知识创新、科研创新、产品转化创新3个阶段,运用空间面板收敛模型对各类创新活动进行收敛检验,研究结果显示：①空间自回归因子和扰动项的空间滞后因子对创新增长率有显著正向影响,说明创新水平增长在地区间具有显著的空间效应,存在空间示范效应和外生冲击传递效应,同时空间面板模型拟合效果整体上优于普通面板模型,说明我国创新活动收敛中有必要考虑空间因素;②知识创新和知识转化创新水平存在稳定的绝对β收敛,科研创新水平不存在收敛,通过基尼系数时序图验证了我国科研创新活动存在“马太效应”,另外两类创新活动水平则朝着收敛的趋势发展;③高校资源、市场化水平分别对知识创新和产品转化创新收敛有显著促进作用,信息化水平对三大创新活动收敛都有显著的促进作用。