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.     

web性能测试研究

本文通过对网上web的订餐系统进行测试,通过设计测试方案,对程序进行系统的单元测试,收集测试数据,对测试数据进行分析等手段,最终生成相关资料及最终测试报告,探讨了软件测试技术在Web中的研究和实现。     

Assessing Aggregate Structural Change

The aim of this paper is to investigate the evolution of Italian aggregate structural change over the years 1965–85. We use annual input–output (IO) tables in current and constant prices to derive an aggregate index of structural change. We adopt several techniques for such an explorative analysis. First, we borrow from qualitative matrix analysis and graph theory some basic concepts to assess direct and indirect links among sectors, and interrelatedness measures are derived in a straightforward way. However, qualitative analysis of indirect links may be flawed, since it can establish a path that is quantitatively negligible. Then, we turn our attention to a non-standard quantitative index derived from structural path analysis, expressed by a simple function of the input matrix determinant. Since empirical findings indicate a structural break in 1975, we derive another measure of technical change: the dominant eigenvalue. Such an index has several interesting properties but no clear relationship to the circularity process implicit in the Leontief model. Results for constant- and actual-price IO tables are discussed and compared with main macro-economic variables over the sample. Empirical findings indicate a relationship between investment, variability in final demand and aggregate structural change.     

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。     

The Impact of Carbon Performance on Climate Change Disclosure

In the light of the significant role of environmental accounting in sustainable development, this study examines whether climate change disclosure reflects a firm's environmental performance. The novelty of the study stands on the approaches adopted to describe environmental performance. The first approach concerns performance in terms of output, direct and indirect greenhouse gas emissions, while the second one is based on environmental intention of mitigating climate change, including climate change policy and emission reduction initiatives. The Climate Performance Leadership Index is employed as a measure for climate change disclosure level, incorporating initiatives contributing to climate change mitigation, adaptation and transparency. Ordered logit regression is the appropriate methodology for the data employed concerning firms listed on FTSE 350. According to our findings, environmental performance for both adopted approaches entails a positive effect on climate change disclosure, a result that is consistent with voluntary disclosure theory. It is inferred that firms cannot manipulate their information reflecting their actual environmental performance and adopting a forthright and factual attitude towards sustainable development. Finally, findings provide an insight into managers' strategic behavior towards climate change issues. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment     

On Tests for a Normal Mean with Known Coefficient of Variation

Hinkley (1977) derived two tests for testing the mean of a normal distribution with known coefficient of variation (c.v.) for right alternatives. They are the locally most powerful (LMP) and the conditional tests based on the ancillary statistic for μ. In this paper, the likelihood ratio (LR) and Wald tests are derived for the one‐ and two‐sided alternatives, as well as the two‐sided version of the LMP test. The performances of these tests are compared with those of the classical t, sign and Wilcoxon signed rank tests. The latter three tests do not use the information on c.v. Normal approximation is used to approximate the null distribution of the test statistics except for the t test. Simulation results indicate that all the tests maintain the type‐I error rates, that is, the attained level is close to the nominal level of significance of the tests. The power functions of the tests are estimated through simulation. The power comparison indicates that for one‐sided alternatives the LMP test is the best test whereas for the two‐sided alternatives the LR or the Wald test is the best test. The t, sign and Wilcoxon signed rank tests have lower power than the LMP, LR and Wald tests at various alternative values of μ. The power difference is quite large in several simulation configurations. Further, it is observed that the t, sign and Wilcoxon signed rank tests have considerably lower power even for the alternatives which are far away from the null hypothesis when the c.v. is large. To study the sensitivity of the tests for the violation of the normality assumption, the type I error rates are estimated on the observations of lognormal, gamma and uniform distributions. The newly derived tests maintain the type I error rates for moderate values of c.v.     

Tests for Stationarity in Series with Endogenously Determined Structural Change*

We consider tests of the null hypothesis of stationarity against a unit root alternative, when the series is subject to structural change at an unknown point in time. Three extant tests are reviewed which allow for an endogenously determined instantaneous structural break, and a related fourth procedure is introduced. We further propose tests which permit the structural change to be gradual rather than instantaneous, allowing the null hypothesis to be stationarity about a smooth transition in linear trend. The size and power properties of the tests are investigated, and the tests are applied to four economic time series.     

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.     

对我国公路运输结构变化及其演进趋势的分析

在我国加速经济发展方式转变的背景下,公路运输作为国民经济重要的基础产业,应以怎样的运输结构来适应其转变是一个具有全局性和长远性的问题。通过对公路运输结构的变化及其影响因素进行分析,提出了公路运输业演进的一般趋势,为我国公路运输结构的合理发展提供了借鉴。     

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。     

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。     

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.     

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。