长江经济带农业水资源利用效率时空差异分析

长江经济带水资源总量充沛,但人均水资源量以及单位面积耕地占有量处于较低水平;农业用水量超过供水总量的50%,而农业水资源利用效率低。研究长江经济带农业水资源利用效率对保护长江具有重要的现实意义。基于Malmquist-Panel Data两阶段模型,对长江经济带农业水资源利用效率的时空差异特征及其影响因素进行了分析研究。分析结果表明:经济发展水平、第一产业固定资产投资额、水资源禀赋、节水农业发展水平、"长江经济带"国家战略的实施、区域变量以及部分时间变量等对农业水资源利用效率具有显著的正向影响,而种植结构即粮食播种面积占比则有着显著的负向影响;长江经济带农业水资源利用效率时空差异特征明显。因此,对于长江经济带,应因地制宜、合理规划农作物种植结构;同时,加强地区间的技术交流与合作,实现长江经济带整体发展与各区域特色发展协同共进。     

基于Malmquist的重庆市科研院所知识生产效率分析

利用中国31个省市自治区科研院所2009—2011年的数据,采用DEA（Data Envelopment Analysis,数据包络分析）和Malmquist指数分析方法从静态和动态两个角度对重庆市科研院所的知识产出效率进行比较分析,并利用DEA-Tobit两步法找出影响科研院所效率的主要影响因素。研究发现：重庆市科研院所的知识生产效率总体处于偏低状态,其科技资源的利用效率存在提升空间;重庆市科研院所未来改革的方向应集中在财政资助方式的变革,加大博士层级的科技人才培养力度,以及提高科技人才劳务支出等。最后提出了相应的政策建议。     

Service quality,technical efficiency and total factor productivity growth in Pakistan's post-reform electricity distribution companies

Pakistan's energy sector has undergone substantial reforms during the last three decades with the aim to improve its operational performance and to cater to the growing energy needs of the economy. In the wake of these reforms, the WAPDA Act was passed in 1998 to achieve operational and financial efficiencies. Pakistan's electricity market is still hampered by issues like extended blackouts, electricity thefts, high circular debt and poor service quality. The electricity distribution sector is thus an interesting case to investigate its efficiency in the post-reform period by examining the impact of service-quality parameters (SQPs), which have generally been neglected in the literature. Stochastic frontier analysis has been used to estimate technical efficiency, while the Malmquist Productivity Index is implemented to decompose total factor productivity (TFP) into scale change, technical change and efficiency change from 2006 to 2016. We conclude that the technical efficiency score declines from 98 percent to 36 percent with the inclusion of SQPs in the models. The results also indicate a negative trend in scale change, implying that distribution companies are not operating at the technically optimal scale. We propose that the regulatory body should change its governance regime and focus on incentive-based regulation instead of rate-of-return regulation.     

How efficient are African electricity companies? Evidence from the Southern African countries

This paper is a first attempt at documenting efficiency levels in Africa's electricity firms, their evolution and the sources of this evolution. The analysis is based on a sample of 12 operators providing services in the 12 country members of the Southern Africa Power Pool. We focus on the changes in total factor productivity (TFP) of the largest operators in each country between 1998 and 2005. We then rely on a data envelopment analysis (DEA) decomposition to identify the sources of the changes in TFP. The results suggest fairly comparable levels of efficiency in the region and performance levels and evolution quite independent of the degree of vertical integration, the presence of a private actor or the main sources of energy supply. The analysis suggest that although the companies have not made significant improvements during the period of analysis in using their capital and human assets, they have done much better in adopting better technologies and better commercial practices. No clear correlation could be associated with the adoption of reforms during the last decade and data limitations impede a more refined assessment of the impact of reforms on efficiency at this stage.     

建筑业全要素生产率影响因素及发展特征分析

为了科学、系统地评价建筑业整体生产效率及发展水平,基于聚类分析和回归分析筛选出影响建筑业生产效率的投入、产出因素。在此基础上运用数据包络分析方法（ DEA）和 Malmquist 模型,从静态和动态角度分析了 2000~2019 年我国31 个省市的建筑业生产效率及发展特征。结果表明:我国建筑业整体效率仍不高;不同地区生产效率差异明显,阻碍了整体效率的提升;各地区建筑业全要素生产率都有所提高,主要由技术进步驱动。并提出优化产业结构,推进区域合作,迈向智能建造的建筑业高质量发展建议。     

基于超效率DEA的火力发电企业能源效率研究

在全要素能源效率框架下建立超效率DEA模型,对河北省13家大型火电企业的全要素能源效率进行了测算和排序,分析了各企业的节能空间,同时基于Malmquist指数对各企业在2009—2011年间的效率变动进行了测算和分解。结果表明:样本期间河北省13家火电企业全要素能源效率稳步提升,但企业间效率差距逐渐加大;火电企业的节能潜力较大,在现有技术水平下,各企业平均每年能源消耗仍有10%以上的可降空间;Malmquist指数分解结果表明技术进步是推动全要素能源效率上升的主导力量。在实证分析的基础上,对提升火电企业的能效水平提出了政策建议。     

Investigating the driving factors of regional CO2 emissions in China using the IDA-PDA-MMI method

In this paper, we systematically summarized existing research on the driving factors of CO₂ emissions and found that changes in technology gap may be one of the key driving factors of CO₂ emissions. Technology efficiency, technology progress, and technology gap were decomposed by using the Meta-frontier Malmquist index (MMI), which was then combined it with the Index Decomposition Analysis (IDA) and the Production-theoretical Decomposition Analysis (PDA). Our framework was applied to Chinese provincial data from 2000 to 2016. We identified nine factors to explain changes of regional CO₂ emissions. Results demonstrate that economic scale, energy technology efficiency, and output technology efficiency increased CO₂ emissions in Eastern, Central, and Western regions of China, with the economic scale being the largest contributor. Energy structure, energy intensity, energy technology progress, and output technology progress decreased regional CO₂ emissions, with the energy technology progress playing the strongest role. Energy technology gap and output technology gap led to an increase in CO₂ emissions in Central China and, to a lesser extent, in Western China. The effects of each driving factor on CO₂ emissions varied across provinces. Finally, policy implications are suggested to reduce CO₂ emissions in China.     

中国乳制品加工业生产效率实证研究——基于超效率DEA及Malmquist指数的分析

运用中国乳制品加工业2003-2010年的省际面版数据,采用非参数的超效率DEA及Malmquist指数,对中国乳制品加工业生产效率进行测定,并对中国乳制品加工业生产效率的变动情况进行分解研究.研究表明,尽管中国乳制品加工业生产效率整体偏低,但是生产效率却以年均10.4％的速度增长,不断靠近生产前沿面;五大奶业产区的生产效率的增长也均为正值,技术进步和技术效率的增长是中国乳制品加工业生产效率增长的双动力.     

Benchmarking the efficiency of natural gas distribution utilities in Italy considering size,ownership, and maturity

In light of the reform of the Italian natural gas distribution introduced in 2007, this work performs a benchmarking and productivity analysis of distribution utilities, identifying the characteristics allowing greater efficiency. Using a Data Envelopment Analysis (DEA) and the Malmquist Productivity Index (MPI), we analyse the performances of utilities and compares them in terms of size, ownership (public or private), and maturity (pre or post-liberalization establishment). The results show that the more efficient utilities are mainly publicly owned and pre-liberalization established. Small and medium-sized utilities operate less efficiently than large ones, revealing the scale inefficiency of the sector.     

Productivity of wastewater treatment plants in the Valencia Region of Spain

This study analyses the evolution of productivity over the 2008–2012 period for a homogenous set of 199 wastewater treatment plants that are located in the Valencia Region of Spain and utilize the same treatment technology, using the smoothed bootstrap Malmquist productivity index based on Data Envelopment Analysis (DEA). The results reveal a negative trend in productivity that is mainly the result of resource management rather than an inappropriate level of innovation or use of new technologies. In addition, the effect of exogenous factors on productivity is analysed using the Kruskal-Wallis (KW) test, finding that productivity levels were affected by the quality of the influent water and the size of the plants, but not by the other factors considered.