“多项连乘和加总”的因素分解法在能源平衡表中的应用

本文对各种研究方法进行分类比较,并指出它们之间的相通性;接着指出在实证研究中普遍存在由于经济部门、产业结构、能源种类等划分的宽口径带来的实验误差：宽口径处理方法的盛行一方面是由于详尽数据的获得存在难度;另一方面,是因为国内外现有研究都是采取“单项连乘和”的形式,这极大限制了分解表达式的涵盖范围和因子种类。为了克服实证研究误差,本文提出将“单项连乘和”扩展成“多项连乘和的加总”形式,并对这种新的方程形式进行因素分解的计算和求解,最后将新方法运用到北京市2000年-2011年的能源平衡表中,分解终端能源消费,获得了细致合理的实验结果。     

Efficiency of the Warsaw Stock Exchange: Analysis of Selected Properties

The Warsaw Stock Exchange (WSE) has been operating in present form for 15 years. WSE is regarded as an “emerging market”. We can observe that it is still developing (in order to become “developed market”). The level of development is often analyzed with reference to the efficiency of the market. We can say that the capital market is efficient if the prices at the market fully reflect all available information. The aim of the presented research is to analyze the current situation at the Warsaw Stock Exchange. Particularly we investigate the weak form of efficiency using selected statistical tests. The research is based on actual data concerning daily observations of shares at the Warsaw Stock Exchange transformed to the logarithmic rates of return, considering the period 2000–2006 and subperiods: the bear market, stagnation and the bull market.

Decomposition of energy-related CO2 emission over 1991-2006 in China

This paper presents a decomposition analysis of energy-related CO₂ emission in China for the period 1991-2006 divided into three equal time intervals. The complete decomposition method developed by Sun is used to analyze the nature of the four factors: CO₂ intensity, energy intensity, structural changes and economic activity. The results show that economic activity has the largest positive effect in CO₂ emission changes in all the major economic sectors and China has achieved a considerable decrease in CO₂ emission mainly due to the improved energy intensity. However, the impact of CO₂ intensity and structural changes is relatively small. Structural changes only exhibit positive effect to the CO₂ mitigation in agricultural sector, and CO₂ intensity also contributes to the decrease of CO₂ emission in transportation sector. Moreover, a formula about CO₂ mitigation is presented in this paper, which shows that China has made a significant contribution to reducing global CO₂ emission.     

Economic growth, international trade and air pollution: A decomposition analysis

This study analyzes the impact of economic growth and international trade on the level of air pollution. This is done by the estimation of the Structural Equation Model with two factors describing the structure of economic activity and air pollution intensity. It is further assumed that there is causal link between these two factors and that they are influenced by per capita income, international trade intensity and the Freedom House Index.The estimation results suggest that in the developing countries analyzed both international trade and per capita income lead to changes in the structure of economic activity and - as a consequence - to the increase in air pollution. In addition, the estimation results suggest that the impact of economic growth on air pollution intensity varies between the developing and developed countries. In the developing countries, this impact occurs through the change of the structure of economic activity, while in the developed countries, this impact is mainly direct and occurs through the sum of the scale effect and income effect. The positive sign of this impact suggests the dominance of the scale effect over the income effect.     

Sources of variation in firm profitability and growth

This article reports an analysis of the sources of variation in profitability and growth for manufacturing firms located in eleven European countries. A variance decomposition analysis determines the importance of the country, industry, corporate group and firm effects on profitability and growth. The analysis reveals evidence of differences between industries in the comparative advantage offered by different countries, reflecting a tendency for specialization and geographic concentration. However, as in several previous studies, the firm-level effects are the most important class of effect in explaining the variation in performance.     

Decomposing the sales promotion bump accounting for cross-category effects

Extant research on the decomposition of unit sales bumps due to price promotions considers these effects only within a single product category. This article introduces a framework that accommodates specific cross-category effects. Empirical results based on daily data measured at the item/SKU level show that the effects of promotions on sales in other categories are modest. Between-category complementary effects (20%) are, on average, substantially larger than between-category substitution effects (11%). Hence, a promotion of an item has an average net spin-off effect of (20 − 11 =) 9% of its own effect. The number of significant cross-category effects is low, which means that we expect that, most of the time, it is sufficient to look at within-category effects only. We also find within-category complementary effects, which implies that competitive items within the category may benefit from a promotion. We find small stockpiling effects (6%), modest cross-item effects (22%), and substantial category-expansion effects (72%). The cross-item effects are the result of cross-item substitution effects within the category (26%) and within-category complementary effects (4%). Approximately 15% (= 11% / 72%) of the category-expansion effect is due to between-category substitution effects of dependent categories.     

Mean square error estimation in multi-stage sampling

Summary: Suppose for a homogeneous linear unbiased function of the sampled first stage unit (fsu)-values taken as an estimator of a survey population total, the sampling variance is expressed as a homogeneous quadratic function of the fsu-values. When the fsu-values are not ascertainable but unbiased estimators for them are separately available through sampling in later stages and substituted into the estimator, Raj (1968) gave a simple variance estimator formula for this multi-stage estimator of the population total. He requires that the variances of the estimated fsu-values in sampling at later stages and their unbiased estimators are available in certain `simple forms'. For the same set-up Rao (1975) derived an alternative variance estimator when the later stage sampling variances have more ‘complex forms’. Here we pursue with Raj's (1968) simple forms to derive a few alternative variance and mean square error estimators when the condition of homogeneity or unbiasedness in the original estimator of the total is relaxed and the variance of the original estimator is not expressed as a quadratic form.  We illustrate a particular three-stage sampling strategy and present a simulation-based numerical exercise showing the relative efficacies of two alternative variance estimators. Received: 19 February 1999     

粤港澳大湾区绿色经济合作效率研究

区域协调发展战略是国家重大战略之一,粤港澳大湾区是践行区域协同发展战略进而引领全国高质量发展的重大空间载体。为了探究粤港澳大湾区内城市间合作潜力,文章基于各城市的政府工作报告,整理并提取可能的合作组合,借鉴Bogetoft and Wang(2005)提出的DEA合并效率测量方法,以“事前”评价角度对粤港澳大湾区城市的绿色经济合作效率及其分解效率进行测算。结果显示,从整体层面看,大部分城市合作组合都是技术效率和协同效率提升,但规模效率下降;合作效率提升主要是由技术效率带动的,合作效率下降则主要是由规模效率导致的。从个体层面看,珠海和江门,珠海、江门和中山,珠海和中山等组合的合作潜力被看好;合作效率提升最多的前10种资源流动路径的样本城市大部分是综合实力略微靠后的城市,这说明综合实力较弱的城市的合作潜力可能较大;合作潜力较高的组合基本都是双边合作,说明双边合作的获益潜力更大。将样本城市进行分类研究,一类是在资源流动前已处于技术边界的样本城市,另一类是在资源流动前处于技术边界以下的样本城市,结果和上述分析一致。研究表明,城市间合作问题纷繁复杂,涉及政治、经济等多方面因素,各城市本身发展存在...     

Regulatory reform and market efficiency: The case of Indian agricultural commodity futures markets

We present the results of two efficiency measures that include intraday return predictability measure based on order imbalance and measures of several variance ratio tests on intraday subsamples of nine major Indian agricultural commodity futures (castor seed, cotton oil cake, rape mustard seed, soybean, refined soya oil, crude palm oil, jeera, chana, and turmeric) quoted in the National Commodity and Derivatives Exchange (NCDEX). We perform the efficiency measures on five subsamples with holding periods of 5, 10, 15, 30, and 60 min over two sample periods following the announcement of the merger between the Forward Market Commission (FMC) and Securities Exchange Board of India (SEBI). We compare results of tests of weak-form market efficiency of futures markets between two periods (pre-merger period and post-merger period). Our results confirm that Indian agricultural commodity futures markets continue to remain inefficient in the short-term during both pre-merger and post-merger periods. Based on these findings, it is likely that profitable trading strategies in the short intraday intervals will be available for traders and market participants during post-merger period. Thus, regulators must focus more on policy initiative so as to enhance market quality in order to address such inefficiencies in Indian commodity futures markets.     

Nexus between telecommunication infrastructures,economic growth and development in Africa: Panel vector autoregression (P-VAR) analysis

This study examines the causal-effect relationship between telecommunication infrastructures, economic growth and development in selected African countries. It further estimates the trivariate impacts of telecommunication infrastructures, economic growth and development in the region. The analysis considers a panel of forty-six African countries from 2000 to 2015. To measure economic growth, real gross domestic product serves as the proxy, while economic development is measured by the Human Development Index, and telecommunication infrastructures by a composite index of telecommunication computed from mobile line, fixed line and internet access penetration via principal component analysis (PCA). The empirical results suggest the existence of a bidirectional long-run relationship between telecommunication infrastructures, economic growth and development. The causality tests reveal that there is feedback causality between telecommunication infrastructures, economic growth and development. Telecommunication infrastructures promote economic growth and development in Africa and vice versa. Thus, there is need to promote inclusive and holistic policies that will enhance digital provide, economic growth and development simultaneously in Africa. An increase in telecommunication infrastructures will encourage aggregate output and standard of living to move in the same direction in Africa.