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1.
由已知n阶矩阵A构造一个n阶矩阵序列A~(k)(k=1,…,n)以及相应的初等变换矩阵E_(kx),然后利用矩阵的乘法,递推求得A的逆或断定A不可逆。并且给出了算法和理论依据。  相似文献   
2.
创新型企业组织形式的设计   总被引:3,自引:0,他引:3  
创新型企业在组织构成上与传统企业有很大的不同,它是为了达到技术和产品创新的目的,在不同专业领域进行一定方式的分工和合作的一批高素质技术人员的集合。因此,在组织上,创新型企业就要不同于传统企业的直线职能式的组织结构。经研究,它应以项目组为组织的基本单元,建立矩阵式的组织结构,充分利用人力资源,灵活、快速地适应环境的变化。  相似文献   
3.
Summary. We exploit the existence of matrix group symmetries on a production possibility set to identify group symmetries on the profit function. The groups are isomorphic, and provide a pre-ordering on firm preferences over prices. Together with additional structure on the technology, symmetries generate comparative statics on price responses. Linear and other invariances place bounds on firm choice vectors. Reflection group asymmetries on the feasible choice set also support welfare rankings over prices. The methods are adapted to study consumer decisions.Received: 12 August 2002, Revised: 30 January 2004, JEL Classification Numbers: D11, D21, C60, L23. Correspondence to: David A. Hennessy  相似文献   
4.
The impact of price and price changes should not be ignored while designing algorithms for predicting customer choice. Consumer preferences should be modeled with consideration of price effects. Businesses need to consider for efficient prediction of an individual's purchase behaviour. Personalized recommendation systems have been studied with machine learning algorithms. However, the price-aware personalized recommendation has received little attention. In this paper, we attempt to capture insightful economic results considered in the marketing and economics disciplines by employing modern machine learning architecture for predicting customer choice in a large-scale supermarket context. We extract personalized price sensitivities and examine their importance in consumer behaviour. The employed data collected from a supermarket chain in Germany consists of implicit feedback based on customer-product interactions and the price of every interaction. We propose a two-pathway matrix factorization (2way-MF) model that is price-aware and tries to memorize customer-product interaction's implicit feedback. The proposed models achieve better model performance than standard Matrix Factorization models widely used in the industry. The approach was re-validated with data from supermarket chain in Taiwan. Other industries can adopt the proposed framework of modeling customer's preferences based on price sensitivity. We suggest that further research and analyses could help understand the cross-price elasticities.  相似文献   
5.
Numerous methods have been proposed to update input–output (I–O) tables. They rely on the assumption that the economic structure will not change significantly during the interpolation period. However, this assumption may not always hold, particularly for countries experiencing rapid development. This study attempts to combine forecasting with a matrix transformation technique (MTT) to provide a new perspective on updating I–O tables. Under the assumption that changes in the trend of an economic structure are statistically significant, the method extrapolates I–O tables by combining time series models with an MTT and proceeds with only the total value added during the target years. A simulation study and empirical analysis are conducted to compare the forecasting performance of the MTT to the Generalized RAS (GRAS) and Kuroda methods. The results show that the comprehensive performance of the MTT is better than the performance of the GRAS and Kuroda methods, as measured by the Standardized Total Percentage Error, Theil's U and Mean Absolute Percentage Error indices.  相似文献   
6.
研究目标:本文研究如何测量国际资金循环(Global Flow of Funds,GFF),试图整合国际金融相关数据源,创建GFF统计矩阵。研究方法:讨论了GFF的基本概念,确定了国际资金循环的统计范围。按照2008SNA所提倡的From Whom to Whom 的统计基准,建立了GFF的统计框架,据此框架整合了国际金融组织之间的数据系统关系和现有的国际金融统计数据源。研究发现:利用相关统计创建了GFF矩阵模型表,试编了一个包含中国在内的由11个国家所构成的“国家×国家”的GFF统计矩阵表。研究创新:创建了GFF矩阵表,展开了以中国为主要观测对象的国际跨境资本比较分析。研究价值:建立了观测GFF统计,开辟了新的分析视野,客观揭示了中国在GFF中的状况及现存的主要问题。  相似文献   
7.
In this paper, we propose a method for improving the accuracy of the estimation of interregional input–output tables, by combining the RAS method and the real-coded Genetic Algorithm (GA); these are simple representative methods for the estimation of an interregional input–output table. By comparing the performance evaluation results obtained using the proposed method, the RAS method, and Simulated Annealing, we verified that the combination of the genetic algorithm and the RAS method can enhance the estimation accuracy of an interregional input–output table. In addition, performance is further enhanced by adjusting GA parameters.  相似文献   
8.
In the conceptual framework of adaptation policy assessment to climate change, adaptation measures can be categorized as two groups:facilitation and implementation. Facilitation measures refers to activities that enhance adaptive capacity, while implementation refers to activities that actually avoid adverse climate impacts on a system by reducing its exposure or sensitivity to climatic hazards, or by moderating relevant non-climatic factors. This paper aims to establish a matrix of implementation measures of adaptation to climate change, through four different ways how adaptation can influencc the relevant elements of climate change. reducing the exposure, reducing the sensitivity, alleviating the adverse impacts and reducing the negative non-climatic factors, and then further discuss the particular implementation measures of adaptation to climate change, through application studies on the selected sub-systems, intend to organize the disordered implementation measures in existent, and put forward some new measures under the guidance of this matrix, which could enrich and promote the system and content of implementation measures of adaptation.  相似文献   
9.
利用阵列天线系统接收信号的自相关矩阵的最大特征值所对应的本征向量的信号处理(PSM)思想,提出一种适用于TD—SCDMA系统的快速下行波束形成技术。此方法利用各个用户的扩频码进行目标用户的数据分离,并用迭代的方法代替用户信号的自相关矩阵的特征分解,降低了计算复杂度。计算机仿真验证了该方法的有效性。  相似文献   
10.
本文在对“模糊决策”进行深入研究的基础上,给出了多层次综合择优决策数学模型。首先提出了“效果值”的概念,解决了模糊排序中的一个难题,从而使决策结果择优更具科学性与合理性。该模型可广泛应用于社会、经济诸领域.  相似文献   
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