Data envelopment analysis (DEA) has become a standard non parametric approach to productivity analysis, especially to relative efficiency analysis of decision making units (DMUs). Extended to the prediction field, it ...Data envelopment analysis (DEA) has become a standard non parametric approach to productivity analysis, especially to relative efficiency analysis of decision making units (DMUs). Extended to the prediction field, it can solve the prediction problem with multiple inputs and outputs which can not be solved easily by the regression analysis method.But the traditional DEA models can not solve the problem with undesirable outputs,so in this paper the inherent relationship between goal programming and the DEA method based on the relationship between multiple goal programming and goal programming is explored,and a mixed DEA model which can make all factors of inputs and undesirable outputs decrease in different proportions is built.And at the same time,all the factors of desirable outputs increase in different proportions.展开更多
That SOEs are inefficient is still a consensus in most economic literature. However, in recent studies, more and more arguments are made in favor of the efficiency of SOEs, yet existing empirical studies are mostly ba...That SOEs are inefficient is still a consensus in most economic literature. However, in recent studies, more and more arguments are made in favor of the efficiency of SOEs, yet existing empirical studies are mostly based on production industry data as samples. On the basis of adopting distribution samples and conducting a cross-sector comparison between the production industry and the distribution sector, this paper offers a multi-perspective empirical assessment on the efficiency of SOEs. Through the analysis of major JTnancial indicators and adopting the Data Envelopment Analysis-Malmquist index for total factor productivity comparison, we find that SOEs generally do not have any disadvantage in efficiency and their superior efficiency is particularly pronounced in the distribution sector as compared with production industry. Moreover, the high share and high efficiency of state capital in the wholesale sector needs particular attention. This paper employs case studies to reveal the positive correlation between the assets-heavy operation of state-owned wholesale firms and their profitability. The implications are as follows： policymakers must deliberate prudently before deciding to withdraw or increase state capital in various sectors; in the wholesale sector where state capital is more efficient, the functions of state capital can be bolstered by increasing its presence in the sector,＂ the notion that state capital must be withdrawn from competitive sectors cannot be adopted likely, nor should the benefits of asset-light operation be exaggerated.展开更多
The study on the enterprise＇s energy efficiency is one of the most important fields of energy efficiency research. Most studies used DEA and aggregate data to estimate the energy efficiency of enterprises. In this st...The study on the enterprise＇s energy efficiency is one of the most important fields of energy efficiency research. Most studies used DEA and aggregate data to estimate the energy efficiency of enterprises. In this study, based on Cobb-Douglas production function, we make a SFA model which takes the energy input and CO2 emission into account. By using the SFA model, we calculate the refineries＇ total-factor energy efficiency with Sinopec refineries＇ micro-data from 2004 to 2009. Meanwhile, we do empirical study on the factors which influence the energy efficiency. In the last, we put forward some advices so as to improve energy efficiency.展开更多
To investigate the long-term operating efficiencies of container ports, we extend the work of previous researches to present a new systemic and improved method of data envelopment analysis （DEA）-based Malmquist prod...To investigate the long-term operating efficiencies of container ports, we extend the work of previous researches to present a new systemic and improved method of data envelopment analysis （DEA）-based Malmquist productivity index （MPI） in this paper. An approach based on both panel data and multi-inputs/outputs is considered comprehensively, and aims at measuring the operating efficiencies of 10 leading container ports in China from 2001 to 2006 by applying this new systematic influence factor of total factor productivity change is the calculation method. The results illustrate that the main technology change, and the container transportation of these 10 ports is on the healthy development status and will recover and grow reposefully in the following years展开更多
A number of process-based models have been developed for quantifying carbon(C)sequestration in agro-ecosystems.The DeNitrification-DeComposition(DNDC)model was used to simulate and quantify long-term(1980-2008)soil or...A number of process-based models have been developed for quantifying carbon(C)sequestration in agro-ecosystems.The DeNitrification-DeComposition(DNDC)model was used to simulate and quantify long-term(1980-2008)soil organic carbon(SOC)dynamics in the important rice-producing province,Jiangsu,China.Changes in SOC storages were estimated from two soil databases differing in spatial resolution:a county database consisting of 68 polygons and a soil patch-based database of 701 polygons for all 3.7 Mha of rice fields in Jiangsu.The simulated SOC storage with the coarse resolution county database ranged between 131.0-320.6 Tg C in 1980 and 170.3-305.1 Tg C in 2008,respectively,while that estimated with the fine resolution database was 201.6 and 216.2 Tg C in 1980 and 2008,respectively.The results modeled with the soil databases differing in spatial resolution indicated that using the soil input data with higher resolution substantially increased the accuracy of the modeled results;and when lacking detailed soil datasets,the DNDC model,parameterized with the most sensitive factor(MSF) method to cope with attribute uncertainty,could still produce acceptable results although with deviations of up to 60% for the case study reported in this paper.展开更多
文摘Data envelopment analysis (DEA) has become a standard non parametric approach to productivity analysis, especially to relative efficiency analysis of decision making units (DMUs). Extended to the prediction field, it can solve the prediction problem with multiple inputs and outputs which can not be solved easily by the regression analysis method.But the traditional DEA models can not solve the problem with undesirable outputs,so in this paper the inherent relationship between goal programming and the DEA method based on the relationship between multiple goal programming and goal programming is explored,and a mixed DEA model which can make all factors of inputs and undesirable outputs decrease in different proportions is built.And at the same time,all the factors of desirable outputs increase in different proportions.
文摘That SOEs are inefficient is still a consensus in most economic literature. However, in recent studies, more and more arguments are made in favor of the efficiency of SOEs, yet existing empirical studies are mostly based on production industry data as samples. On the basis of adopting distribution samples and conducting a cross-sector comparison between the production industry and the distribution sector, this paper offers a multi-perspective empirical assessment on the efficiency of SOEs. Through the analysis of major JTnancial indicators and adopting the Data Envelopment Analysis-Malmquist index for total factor productivity comparison, we find that SOEs generally do not have any disadvantage in efficiency and their superior efficiency is particularly pronounced in the distribution sector as compared with production industry. Moreover, the high share and high efficiency of state capital in the wholesale sector needs particular attention. This paper employs case studies to reveal the positive correlation between the assets-heavy operation of state-owned wholesale firms and their profitability. The implications are as follows： policymakers must deliberate prudently before deciding to withdraw or increase state capital in various sectors; in the wholesale sector where state capital is more efficient, the functions of state capital can be bolstered by increasing its presence in the sector,＂ the notion that state capital must be withdrawn from competitive sectors cannot be adopted likely, nor should the benefits of asset-light operation be exaggerated.
文摘The study on the enterprise＇s energy efficiency is one of the most important fields of energy efficiency research. Most studies used DEA and aggregate data to estimate the energy efficiency of enterprises. In this study, based on Cobb-Douglas production function, we make a SFA model which takes the energy input and CO2 emission into account. By using the SFA model, we calculate the refineries＇ total-factor energy efficiency with Sinopec refineries＇ micro-data from 2004 to 2009. Meanwhile, we do empirical study on the factors which influence the energy efficiency. In the last, we put forward some advices so as to improve energy efficiency.
基金the National Natural Science Foundation of China (No. 50578030)
文摘To investigate the long-term operating efficiencies of container ports, we extend the work of previous researches to present a new systemic and improved method of data envelopment analysis （DEA）-based Malmquist productivity index （MPI） in this paper. An approach based on both panel data and multi-inputs/outputs is considered comprehensively, and aims at measuring the operating efficiencies of 10 leading container ports in China from 2001 to 2006 by applying this new systematic influence factor of total factor productivity change is the calculation method. The results illustrate that the main technology change, and the container transportation of these 10 ports is on the healthy development status and will recover and grow reposefully in the following years
基金Supported by the Knowledge Innovation Program of Chinese Academy of Sciences(Nos.KZCX2-YW-Q1-07 and KZCX2-YW-Q1-15)the National Basic Research Program(973 Program)of China(No.2010CB950702)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA05050509)
文摘A number of process-based models have been developed for quantifying carbon(C)sequestration in agro-ecosystems.The DeNitrification-DeComposition(DNDC)model was used to simulate and quantify long-term(1980-2008)soil organic carbon(SOC)dynamics in the important rice-producing province,Jiangsu,China.Changes in SOC storages were estimated from two soil databases differing in spatial resolution:a county database consisting of 68 polygons and a soil patch-based database of 701 polygons for all 3.7 Mha of rice fields in Jiangsu.The simulated SOC storage with the coarse resolution county database ranged between 131.0-320.6 Tg C in 1980 and 170.3-305.1 Tg C in 2008,respectively,while that estimated with the fine resolution database was 201.6 and 216.2 Tg C in 1980 and 2008,respectively.The results modeled with the soil databases differing in spatial resolution indicated that using the soil input data with higher resolution substantially increased the accuracy of the modeled results;and when lacking detailed soil datasets,the DNDC model,parameterized with the most sensitive factor(MSF) method to cope with attribute uncertainty,could still produce acceptable results although with deviations of up to 60% for the case study reported in this paper.
