Another Look at Chow's Test for the Equality of Two Heteroscedastic Regression Models

This paper reviews tests of equality between the sets of coefficients in thetwo linear regression models, and examines the effect of heteroscedasticityin each model on the behaviour of one such test. A Monte Carlo evaluation,of the size in particular, shows that the usual Chow's F-ratio is wellbehaved as long as the sample sizes in the two models are equal and the twomodels exhibit the same form of heteroscedasticity which is moderate in thecontext of the values used. In such situations it is recommended that thetest be used directly to avoid the extra efforts involved in transformingthe original data in order to attain homoscedasticity.     

变结构门限t-GARCH模型及其伪持续性研究

为了反映金融时间序列的波动集聚性、非对称性、厚尾性以及在实证研究中表现出的伪持续性,本文结合门限GARCH模型以及变结构的方法提出了变结构门限t—GARCH模型。首先用Monte Carlo模拟的方法考虑了变结构GARCH模型中存在的伪持续性问题;其次针对金融时间序列非对称性、厚尾性以及强持续性的特点提出了变结构门限t—GARCH模型,总结了关于变结构点检验的几个主要方法;最后用该模型来拟合沪市和深市两个股市的周收益率序列,得到了比GARCH模型更好的拟合结果。     

中国出口结构变革和经济增长的协整分析

本文在以前研究的基础上探讨了出口和经济增长的关系,并考虑出口结构变化对经济增长的影响。不仅证实了出口和经济增长相互促进关系,还证实了出口结构的变化也是促进经济增长的有利因素之一。     

Sources of Structural Change and Output Growth of China's Economy: 1987-92

This paper examines the sources of structural changes in output growth of China’s economy over 1987–92 using a decomposition method within the input-output (IO) framework. The model uses three comparable IO tables of 1987, 1990, and 1992 as the main data sources; it accounts for output changes from a demand side perspective and decomposes the growth of output into consumption demand, investment demand, export, import, and intermediate use (indicated by changes in IO coefficients). Special attention is given to identifying the effects of government policies on economic growth and structural change. It is found that overall output growth was multi-components driven rather than single-factor led; the share of the contribution to output growth from consumption and investment expansion declined and that from export and import increased. Whilst the efficiency of factor utilisation remains an issue of further research, a remarkable rise in IO coefficient share indicates a deepening and strong interdependence between industrial sectors over the data period. This revised version was published online in July 2006 with corrections to the Cover Date.     

Diversity Analysis of Structural Change Based on the Canadian Input–Output Tables

This article presents some of the results of a study conducted at Statistics Canada that involved the analysis of the variability through time of input–output structures. All structures have been analyzed in current and constant prices over the period 1961–84, but only the results about the industries' input structures in current prices are reported in this article. Structural changes are assessed over time horizons of 1, 2 and 5 years, using the Kullback, cross-entropy index formula. Structural changes in the current prices input structure are decomposed into a price and a quantity component, following a new decomposition of the entropy formula. It is shown from that decomposition that the traditional analysis of the variability of constant prices input–output structures may be quite misleading. The authors have found that structural changes generally follow a smooth path through time and tend to be cumulative in the long run, with some cyclical fluctuations in the short term. Some of the structural changes appear to be due to statistical events (establishment moves across industries, changes in methodologies, etc.) rather than reflecting real phenomena. The quantity component of structural change appears to be more important than the price component in almost all time periods and time spans, except when the Canadian economy was subjected to important price shocks during the 1970s.     

Structural Change in Poland, 1980–90: Evidence from Social Accounting Multipliers and Linkage Analysis

The 1980s and the beginning of the 1990s have witnessed a period of economic reforms in Poland. The paper uses aggregated social accounting multipliers to assess whether any structural change at a macro-economic level has taken place in this period. Linkage analysis is adopted to evaluate intersectoral reallocation of resources. The results support the view that some macro-economic adjustment has taken place but they do not provide evidence of significant intersectoral shifts.     

本轮通货膨胀的成因及对策

文中对中国目前通货膨胀的形成原因进行了分析,认为本轮通货膨胀的类型是成本推动型,提出了要谨防由结构性通货膨胀演变为全面通货膨胀,并从货币政策和财税政策两个方面分析如何应对本轮通货膨胀。     

Analytical Problems in Decomposing the System-wide Effects of Sectoral Technical Change

The disaggregated structure of input–output (IO) analysis makes it very attractive in analyzing technical change. Various authors have applied IO models in comparative static experiments to measure the effects of observed technical changes in individual industries on economy-wide total output (or related primary input) requirements. Less often have researchers performed similar analyses on the effects of changes across all consuming industries in the productive consumption of a sector's output, because of the need to append an external analysis of substitution. Despite the obstacles to joint analyses of sectoral production and cross-sectoral consumption change, its appeal has long been recognized. In this paper, an anomaly in such analyses is presented: the sum of the separate effects of changes in production and changes in productive consumption does not equal the effects of the joint change. A comparative static exercise reveals the root cause of the anomaly: essentially, an index number problem. Empirical analyses are performed across a comprehensive set of US sectors to estimate the range of discrepancies.     

Quantifying Structural Change in U.S. Agriculture: The Case of Research and Productivity

Previous work on structural change in agriculture has failed to distinguish long-run trends from structural breaks leading to new trends. We measure structural changes as statistically significant breaks in either stochastic or deterministic time trends, and apply these measures to agricultural productivity and research. Productivity has a break in 1925 accompanying agriculture's early experience with the Great Depression. Research trends shifted in 1930 as the Depression and new technology began to strongly influence efficient farm size and capitalization. After modeling lags between research and productivity impacts in a vector autoregression (VAR), we compare our results to earlier work by developing a procedure to estimate the rate of return to research from the impulse response function of the VAR.     

转型时期制度变迁对我国经济增长影响的实证分析

我国现在进行的改革开放必然会引起制度的变迁,而从经济学理论上讲,制度的变迁又会对经济的发展产生巨大影响。文中制度这一因素引入经济增长模型,并量化测度了制度变迁,并进行实证分析。结果表明,改革开放30多年来我国的制度变迁对经济的增长具有巨大的促进作用。而目前,我国的体制改革尚未完成,仍有较大的制度变迁空间,所以制度创新与变革仍然是我国未来较长一段时期内经济增长的重要动力源泉。     

The Effect of Technological Change and Technical Inefficiencies on the Performance of Functional Forms

Technological change is one of the most important determinants of the technological structure of the firm. Unfortunately, this crucial factor is often unobserved and must therefore be approximated. It is also well recognized that firms are not necessarily located on their efficient production frontier, a phenomenon known as technical inefficiency. This paper compares the performance of three flexible functional forms (the Translog, Symmetric McFadden and Symmetric Generalized Barnett) to properly infer theoretical properties and technology measurements when: (i) unobserved technological change is approximated by a time trend in the variable-cost-function specification and, (ii) firms may be technically inefficient. Our results indicate that no functional form dominates and that measuring the shifts of the production (cost) function has a clear and negative effect on the performance of the functional forms. Furthermore, we find that technical inefficiencies have a significant and negative effect on the measurement of, notably, returns to scale and the implicit rental price of capital. However, all forms over-reject theoretical properties and provide adequate technology measurements only on a sample-average basis. In addition, the performance of the functional forms is closely related to the true underlying rate of technological change.     

土木工程专业《结构试验》课程实验教学改革研究

随着我国基础设施建设迅猛发展,各高校土木工程专业人才的培养也蓬勃兴起。土木工程专业最大的特点是具有极强的实践性,所以在祖国发展的新时期,对土木工程专业大学生动手实验及工程实践能力提出了更高的要求。《结构试验》作为土木工程的实验教学环节中的重要环节之一,要做到能够帮助学生理论联系实践,把学到的理论知识点真正运用到实践的环节中,真正培养学生的动手能力、分析能力、解决问题能力。因此针对土木工程专业学生实践能力培养的现状及结构试验教学存在的问题进行分析,并研究探讨实验教学的改革方法。     

Financial and Structural Stimuli for Regional Growth

The economies during the post-industrial era are returning to the classical meaning of manufacturing sector in the process of balanced regional growth and are searching for stimuli for diversifying economic structure and reindustrialization. Expansion of a new growth theory highlighted the necessity for the well-developed so-called innovative manufacturing sector; however, stimuli for realizing the potential of this sector are limited due to relative attractiveness of sectors with lower risks and faster returns especially in regions followers. Moreover, regional success as a result of the previous development can hinder changes and stimulate economic agents to avoid regions and sectors with high potential but weak performance. Generation of regional economic growth can be considered in a framework of two kinds of stimuli as financial and structural. Financial capital as an important factor for supporting structural change in economy helps to stay in harmony with the modern economy; however, existing sectoral composition can be persistent to changes. Latvia is considered as a case study about issues on fmancial and structural stimuli for regional growth because of the bright dominance of capital city region （high regional differentiation） and typical post-industrial economic structure in parallel with an intention to actively participate in reindustrialization and increase the innovativeness of economy. This article searches whether foreign investment stock in a company＇s equity capital provides a stimulus for an industrial change at a micro level （five regions and 12 manufacturing sectors in accordance with statistical classification of economic activities NACE 2 Rev. （Nomenclature generale des Activities economiques dans les Communuates Europeennes） two-digit level） and whether this change contributes to the regional growth. Unbalanced regional growth as a result of reallocation of financial resources among sectors of economic activity and differences in distribution of economic success at a sector     

兰尖铁矿无底柱分段崩落法结构参数研究与确定

本文对兰尖铁矿无底柱分段崩落法结构参数的选择进行了研究分析,指出了参数选择的依据,对其它类似矿山选择结构参数提供了参考。     

宽体车车架结构分析与整车性能验证

本次研发的宽体车总质量为40t,是在总质量60t级平台产品的基础上向下衍生而来的。应用三维造型软件建立了矿用自卸车实体几何模型,并对关键结构——车架给出了应力分析时的模型简化方法,根据整车的装配关系和车架的受力特点确定了车架强度有限元分析的边界条件,在此基础上建立了包括车桥、悬挂和车厢在内的整车有限元模型,依据矿用车的典型受力重点选取满载静止或平稳行驶、扭转组合和侧倾举升作业作为分析工况,应用ANSYS软件求解得到各工况下车架的应力大小和应力分布规律。为验证整车的性能,在华润水泥南宁公司矿山对样车进行了为期3个月的性能试验,并对该矿车进行了全面检验,为下一步优化设计提供依据。     

宽体车车架结构分析与整车性能验证

本次研发的宽体车总质量为40t,是在总质量60t级平台产品的基础上向下衍生而来的。应用三维造型软件建立了矿用自卸车实体几何模型,并对关键结构——车架给出了应力分析时的模型简化方法,根据整车的装配关系和车架的受力特点确定了车架强度有限元分析的边界条件,在此基础上建立了包括车桥、悬挂和车厢在内的整车有限元模型,依据矿用车的典型受力重点选取满载静止或平稳行驶、扭转组合和侧倾举升作业作为分析工况,应用ANSYS软件求解得到各工况下车架的应力大小和应力分布规律。为验证整车的性能,在华润水泥南宁公司矿山对样车进行了为期3个月的性能试验,并对该矿车进行了全面检验,为下一步优化设计提供依据。     

协整向量误设对相关检验的影响

常用于检验既定协整关系的统计量有tDF和tECM两种，但由于真实数据生成过程未知，估计模型中可能存在一定程度的协整向量误设，从而使统计量的分布特征受到影响。本文首先探讨tDF检验的隐含系数约束α=γ，即短期弹性等于先验长期弹性；其次分析零假设下两种统计量的分布特征，以及先验设定γ对信号噪声比q进而对tECM分布特征的影响；最后在局部备择假设下，给出两种统计量的渐近分布，并表明向量误设会降低协整检验的势，其程度与设定误差d正相关。     

The Asymptotic Efficacies and Relative Efficiencies of Various Linear Rank Tests for Independence

In this paper we consider eight general models of independence, the Hájek–Šidák model, the Janssen–Mason model, Konijn’s model, Steffensen’s model, the Farlie model, the bivariate Gamma distribution, the Mardia model and the Frechet model. The asymptotic efficacies and relative efficiencies of various linear rank tests are computed. It turns out that the asymptotic power depends heavily on the underlying model. However, for the vast majority of considered models, the Spearman test is, asymptotically, a good choice.     

组织变革、动态能力与创新绩效——基于多案例的研究

本文旨在探讨组织变革、动态能力以及创新绩效之间的影响关系。以新产品开发为视角提出基于NPD的三维动态能力,并利用探索性案例研究方法,以制造业三家具有代表性的企业为分析样本,证实了组织变革对需求识别能力、概念开发能力和产品设计能力与创新绩效之间的关系起到了部分中介影响作用。