The efficacy of using judgmental versus quantitative forecasting methods in practice

In an era where forecasts drive entire supply chains forecasting is seen as an increasingly critical organizational capability. However, business forecasting continues to rely on judgmental methods despite large advancements in information technology and quantitative method capability, prompting calls for research to help understand the reasons behind this practice. Our study is designed to contribute to this knowledge by profiling differences between firms identified as primary users of either judgmental or quantitative forecasting methods. Relying on survey data from 240 firms we statistically analyzed differences between these categories of users based on a range of organizational and forecasting issues. Our study finds large differences in forecast error rates between the two groups, with users of quantitative methods significantly outperforming users of judgmental methods. The former are found to be equally prevalent regardless of industry, firm size, and product positioning strategy, documenting the benefits of quantitative method use in a variety of settings. By contrast, the latter are found to have significantly lower access to quantifiable data and to use information and technology to a lesser degree.     

制造企业服务业务扩展及其认知因素研究

制造企业的竞争越来越激烈,几乎所有的企业都要面对快速反应多变市场和应对价格压力的要求,面对越来越小的产品利润空间和越来越复杂的客户需求,本文从对工业服务管理文献分析和制造企业的调查研究入手,揭示了制造企业从纯粹的产品生产者向客户支持方案提供者发展的转移趋势.通过对瑞士和德国30多家机器和设备制造企业进行的调查研究,说明了服务业务对制造企业在开发财务、营销和战略机会上的重要作用,并对转移过程中服务业务的扩展过程进行了总结.结合具体企业实践,本文对制约制造企业扩展服务业务中在管理动机上的认知因素进行了分析和研究.结合中国加入WTO后,中国制造企业将全面融入国际竞争的背景,本文期望对中国制造企业的发展和竞争地位的提高提供理论和实践上的指导.     

经济收敛理论与检验方法研究综述

在大量文献研究的基础上,对收敛问题的产生及收敛概念的发展作了全面概括,并对绝对收敛、条件收敛、俱乐部收敛和σ收敛作了深入辨析,对各种识别方法作了全面归纳。归纳了对世界大多数国家和地区数据所作识别的结果。还从收敛理论与传统理论的冲突与协调方面作了深入分析。最后对近年收敛研究的深化与扩展研究的趋势作了概括。     

东道国外债规模与中国OFDI——基于发展中国家面板数据的研究

本文利用2003—2013年间中国对外直接投资跨国面板数据,采用系统GMM方法,实证研究发展中国家外债规模与中国OFDI的关系.研究发现,在发展中国家或地区,外债规模与中国对外直接投资存在正向关系.此外,我们还得到东道国外债规模均会弱化市场规模、自然资源、技术水平对中国OFDI的正向作用.     

“调转促”行动下安徽省农业产业化经营组织形成的路径及其动因分析

当下,安徽省正在落实“调转促”行动计划,是调整农业结构、转变农业发展方式、升级传统农业的重要战略机遇。首先阐述了农业产业化经营组织的基本理论,然后重点分析安徽省农业产业化经营组织的形成路径以及动因,并提出了营造农业产业化经营组织发展的孕育环境,扶持当地龙头企业,调整市场环境,健全利益联结机制等措施。     

基于学习动机感知的学生主体分类及其影响因素探究——以江苏省普通高校为实证

以大样本问卷调查为基础,采用多种数理统计方法,进行基于学习动机主观感知为学生主体类型划分及影响因素的研究。发现学习动机表征因素不止于内在和外在,还会体现在近期和远期、物质和精神、自我和他者等其他复杂要素上,而且还会受到入校时间、学校类型、性别以及地缘背景等因素影响。构建与学生主体需求相匹配的教育资源供给梯次和分类指导对促进高校教育具有重要意义。     

Inference for quantile measures of kurtosis,peakedness, and tail weight

Insight into measures of peakedness, heavy-tailedness, and kurtosis can be gained by studying Ruppert’s ratios of interquantile ranges. They are not only monotone in Horn’s measure of peakedness when applied to the central portion of the population, but also monotone in the practical tail-index of Morgenthaler and Tukey, when applied to the tails. Non-parametric confidence intervals are found for Ruppert’s ratios, and sample sizes required to obtain such intervals for a pre-specified relative width and level are provided. In addition, the empirical power of distribution-free tests for peakedness and bimodality are found for some symmetric distributions.     

动态性与静态性:教学目标的确定及实现——以“教育研究方法”课程为例

教学目标的存在有应然状态和实然状态之分。"教育研究方法"课程的静态目标应具体体现为"涵养科学精神、问题意识的形成、基本研究技能的掌握和有效获取文献信息",这些目标在实现过程中必然存在着动态性选择。     

宏观经济学教学方法探讨

本文分析宏观经济学的自身特点,并据此提出相应的有效的教学方法。     

Semi-doubly optimal concentric circles fitting with presence of heteroscedasticity

Previous studies focus on homogeneous and isotropic assumptions about the noisy data. Many methods have been developed recently for fitting concentric circles to data. In this paper, these statistical assumptions have been relaxed. To the best of our knowledge, only one iterative method has been recently developed. Due to its complexity, no such algorithm is available to compute the reliable maximum likelihood estimator (MLE). Accordingly, we have developed four new methods that outperform the existing methods including the orthogonal distance regression (ODR). We also discuss which of these methods is superior according to the four principles: statistical efficiency, accuracy, robustness, and computational efficiency. Numerical experiments on synthetic and real images have been conducted to validate our findings.