耦合Sylvester矩阵方程的梯度迭代算法

通过推广求解矩阵方程AX=b或AX+XB=C的递推迭代算法和基于递阶辩识原理的思想,给出了求解广义耦合矩阵方程的梯度迭代算法。并证明了迭代算法的收敛性。分析表明,若矩阵方程有唯一解,则对任意的初始值该算法给出的迭代解都能快速的收敛到其精确解。数值实例验证了该算法的有效性。     

Using partial least squares in operations management research: A practical guideline and summary of past research

The partial least squares (PLS) approach to structural equation modeling (SEM) has been widely adopted in business research fields such as information systems, consumer behavior, and marketing. The use of PLS in the field of operations management is also growing. However, questions still exist among some operations management researchers regarding whether and how PLS should be used. To address these questions, our study provides a practical guideline for using PLS and uses examples from the operations management literature to demonstrate how the specific points in this guideline can be applied. In addition, our study reviews and summarizes the use of PLS in the recent operations management literature according to our guideline. The main contribution of this study is to present a practical guideline for evaluating and using PLS that is tailored to the operations management field.     

基于拟牛顿法频率域全波形反演研究

全波形反演是综合利用地震波场的运动学和动力学参数,通过最小二乘来拟合实际波场和预测波场,从而获得地质结构和岩性资料的方法。本文先简述了频率域地震波正演,之后利用拟牛顿法来推导频率域全波形反演,克服了高斯——牛顿法中海森矩阵可能奇异或者非正定特性,通过图形对比,得到频率域全波形反演局限在于频率的缺失和来自其它地质结构对三维地质模型受到的影响比较大,合理选择频点和频宽进行反演可解决频率缺失的影响,二维地质模型的反演效果理想,而三维地质模型的反演有待提高和改进。     

解加权约束最小二乘问题的行M-不变方法

本文提出了一种新的求解加权约束线性最小二乘问题方法,即利用行M-不变矩阵得到了求解加权约束线性最小二乘的updating问题的递推方法。     

给排水管道经济综合评价及塑料管道产量预测

通过对常见给排水管道的技术性能、应用、施工经济性的分析,结合矩阵分析法对各种管道进行经济性综合评价,同时,结合最小二乘法,对新型塑料给排水管道的发展进行定性、定量的分析、预测。结果表明,塑料管道的年产量随时间成指数关系增长,在越来越多的市政给排水管道工程中得到推广应用。     

Contamination in linear regression models and its influence on estimators

The consequences of the omission of possibly contaminated observations in a linear regression model for the performance of the ordinary least squares ( LS- ) estimator are discussed. We compare the ordinary L Sestimator with the corresponding 'never pooled' LS -estimator with respect to the matrix-valued mean squared error. Necessary and sufficient conditions are derived for the superiority of an estimator to another one and tests are proposed to check these conditions. Finally the resulting preliminary-test-estimators are investigated.     

Performance of empirical Bayes estimators of random coefficients in multilevel analysis: Some results for the random intercept-only model

For a multilevel model with two levels and only a random intercept, the quality of different estimators of the random intercept is examined. Analytical results are given for the marginal model interpretation where negative estimates of the variance components are allowed for. Except for four or five level-2 units, the Empirical Bayes Estimator (EBE) has a lower average Bayes risk than the Ordinary Least Squares Estimator (OLSE). The EBEs based on restricted maximum likelihood (REML) estimators of the variance components have a lower Bayes risk than the EBEs based on maximum likelihood (ML) estimators. For the hierarchical model interpretation, where estimates of the variance components are restricted being positive, Monte Carlo simulations were done. In this case the EBE has a lower average Bayes risk than the OLSE, also for four or five level-2 units. For large numbers of level-1 (30) or level-2 units (100), the performances of REML-based and ML-based EBEs are comparable. For small numbers of level-1 (10) and level-2 units (25), the REML-based EBEs have a lower Bayes risk than ML-based EBEs only for high intraclass correlations (0.5).     

Efficiency comparisons between two estimators based on matrix determinant Kantorovich-type inequalities

We first establish two matrix determinant Kantorovich-type inequalities. Then, based on these two and other inequalities, we introduce new efficiency criteria and present their upper bounds to make efficiency comparisons between the ordinary least squares estimator and the best linear unbiased estimator in the general linear model. We provide numerical examples to examine the upper bounds of some new and old efficiency criteria. Received: June 1999     

大规模定制(MC)中提高模块化程度优化策略研究

建立了提高产品模块化程度的模型，通过分析产品零件之间的关联度和零件的功能属性、物理属性、成本属性的相似性形成零件之间的关系矩阵，根据关系矩阵得出更高程度的产品模块，从而实现提高产品模块化程度的目标。并应用一个电脑实例说明这种优化方法的可行性。     

模糊层次分析法(FAHP)在供应商评价选择中的应用

人在决策时常有模糊性.然而先前的供应商评价模型却常常忽略了这点.因此本文首先介绍了模糊层次分析法（Fuzzy AHP）,然后提出了实际企业中选择供应商时考虑的因素,最后应用该方法建立了一个供应商模糊评价模型.该模型考虑了人判断的模糊性.在生产实践中,它可以帮助生产企业更准确地选择供应商.     

Past price ‘memory’ in the housing market: testing the performance of different spatio-temporal specifications

Recent methodological developments provide a way to incorporate the temporal dimension when accounting for spatial effects in hedonic pricing. Weight matrices should decompose the spatial effects into two distinct components: bidirectional contemporaneous spatial connections; and unidirectional spatio-temporal effects from past transactions. Our iterative estimation approach explicitly analyses the role of time in price determination. The results show that both spatio-temporal components should be included in model specification; past transaction information stops contributing to price determination after eight months; and limited temporal friction is exhibited within this period. These findings highlight the decidedly non-linear temporal patterns of such information effects.     

论价值管理在企业客户资本管理中的运用

本文从价值管理的角度对企业客户资本管理进行了分析。在价值管理模式下,通过客户资本细分矩阵可以对客户资本投资进行决策,通过价值创造——价值获取矩阵可以对客户资本价值管理活动进行评估。     

基于VE思维的多媒体教学模式改进探讨

分析了多媒体教学的特点,并结合作者在多媒体教学实践中的认识,基于VE思维,对其优缺点进行分析,提出改进教学模式、提高教学效果的方法和途径。     

我国预算管理理论和实践综述

预算管理作为一种管理控制工具,在西方已经经历了四个发展阶段,其间传入我国。经过20多年的发展,预算管理已成为我国企业普遍应用的管理手段。从评述西方预算管理理论开始,重点探讨了预算管理理论在我国的应用。预算管理的实践和发展在我国可以分为四个方面:预算管理基础理论的建立,将预算管理理论和实务的紧密联系,与管理会计工具的整合,以及以创造价值为目标的预算管理。本文可为我国企业更好地运用全面预算管理这一管理会计工具提供借鉴。