Efficiency of Iranian forest industry based on DEA models

Data Envelopment Analysis （DEA） is a mathematical tech- nique to assess relative efficiencies of decision making units （DMUs）. The efficiency of 14 Iranian forest companies and forest management units was investigated in 2010. Efficiency of the companies was esti- mated by using a traditional DEA model and a two-stage DEA model. Traditional DEA models consider all DMU activities as a black box and ignore the intermediate products, while two-stage models address inter- mediate processes. LINGO software was used for analysis. Overall pro- duction was divided into to processes for analyses by the two-stage model, timber harvest and marketing. Wilcoxon＇s signed-rank test was used to identify the differences of average efficiency in the harvesting and marketing sub-process. Weak performance in the harvesting sub-process was the cause of low efficiency in 2010. Companies such as Neka Chob and Kelardasht proved efficient at timber harvest, and Neka Chob forest company scored highest in overall efficiency. Finally, the reference units identified according to the results of two-stage DEA analysis.

Production Efficiency of Two-Oriented Agriculture Based on Three-Stage DEA Model

Two-oriented agriculture was a complex organism coupling production,economics,society and ecology.Its development process was affected by various factors such as producers,nature,society,etc.In order to overcome measurement error of traditional data envelopment analysis caused by ignoring random,three-stage DEA model was studied to remove environmental factors and random effects.On the foundation of this model was two-oriented agriculture comprehensive production efficiency of 14 cities were estimated in Hunan Province in 2008,and brown forth corresponding policy proposals to promote agricultural development.

A Comparative Study on the Land Use Efficiency of Three Urban Agglomerations-Based on the Three-Stage DEA Model

This paper uses a three-stage DEA model to measure the land use efficiency of the three major urban agglomerations in the Yangtze River Delta,Beijing-Tianjin-Hebei,and the Pearl River Delta from 2007 to 2018.The following conclusions are drawn through research:first,the urban land use efficiency of the three major urban agglomerations in the Yangtze River Delta,Beijing-Tianjin-Hebei,and the Pearl River Delta all showed a downward trend,with the rates of decline being 6.06%,2.86%,and 24.34%respectively.In particular,the Pearl River Delta urban agglomeration had the largest decline.Second,the overall urban land use efficiency of the Beijing-Tianjin-Hebei urban agglomeration is relatively high,and the amount of redundancy is relatively small.The rate of decline is significantly lower than the urban land use efficiency of the two major urban agglomerations in the Yangtze River Delta and the Pearl River Delta.The land use efficiency of the Yangtze River Delta and Pearl River Delta urban agglomerations is in a state of continuous decline.Third,the proportion of cities with the effectiveness of returns to scale of urban land use efficiency in the three major urban agglomerations has decreased by 10.53%,10%,and 33.34%,respectively.The Pearl River Delta has the largest decline.Fourth,the land use efficiency of the Yangtze River Delta urban agglomeration is quite different.The central-peripheral phenomenon is evident for the Beijing-Tianjin-Hebei urban agglomerations and the Pearl River Delta urban agglomerations.

Empirical Analysis of Agricultural Cultural Resources Value Evaluation under DEA Model

Agricultural culture is a productive activity about education and management.It aims at high efficiency and high quality,uses technology as its means,and takes nature as its carrier.Agricultural cultural resources are the product of the rapid development of modern economy.It promotes the development of the national economy and profoundly affects people's production and life.DEA model,also known as data envelope analysis method,is an algorithm that uses multiple data decision units for input and output training to obtain the final model.This article explains the concept and basic characteristics of agricultural culture.Through questionnaire surveys and expert interviews,we collected development data,screened human,material,and financial data,and calculated information on economic and social resources.On this basis,this paper establishes the evaluation index of agricultural culture based on DEA model.Then,through empirical analysis from a specific perspective,it can be concluded that increasing human,material and financial input can achieve economic and social benefits.Generally speaking,cultural investment can promote the development of the industry.The research results of this paper laid a theoretical foundation for the development of agricultural culture,and put forward a development model focusing on technology development,improving investment efficiency,and investing in material resources.

Study of Efficiency of Agricultural Listed Companies Based on DEA Model

As leading enterprises supporting the agricultural development,agricultural listed companies play a great role,thus the study on their operating efficiency will have a strong demonstration effect. Using the data envelopment analysis( DEA) model,the operating efficiency of 20 agricultural listed companies was compared and analyzed. The results indicated that the overall efficiency of the agricultural listed companies is low. In agricultural listed companies with low or moderate overall efficiency,some agricultural companies are affected by the pure technical efficiency or scale efficiency,while other companies are affected by both factors,and accompanied with the increasing or decreasing efficiency along with the scale. Through in-depth analysis,it concluded that nine companies affected by pure technical efficiency have different degree of input redundancy or output deficiency. On this basis,it came up with pertinent recommendations for improvement.

The Analysis of the Agriculture Input and Output Efficiency Based on DEA Model

Fiscal agricultural expenditure has been increased rapidly for a long time,but ＂Agriculture,Countryside and Farmer＂ issues have not yet been resolved fundamentally,which illustrates that the main direction of fiscal agricultural expenditure and the appropriate intensity of input have not been discovered exactly before implementing the policy.This thesis analyzed the agriculture input and output efficiency by input-DEA model,and then summarizes bygone problem about fiscal agricultural expenditure.At last,some effective suggestions were proposed about optimizing the agriculture input and output efficiency.

The Optimal Investment Strategy Based on the DEA Model

The Goodgrant Foundation is a charitable organization that wants to improve education performance of undergraduates attending colleges and universities in the US. So the foundation plans to contribute a total of US 50 million for a suitable team of schools per year under the condition of avoiding repeated other large grant organizations’ investment. The DEA (Data Estimate Analysis) model is developed to determine an optimal investment strategy for the Goodgrant Foundation. In this paper, two questions were solved: how to choose a suitable team of schools and how to allocate the investment. Before the establishment of the model, the EXCEL software is used to preprocess data. Then the DEA model which includes two models in the paper is developed. For the first question, the CCR model is established to rank schools which used efficiency from DEAP 2.1. For the second question, the resource allocation model is established to allocate investment amount by weights of allocation from MATLAB software. Accordingly, the optimal investment strategy is received for the Goodgrant Foundation. Through the analysis above, 23 from 293 schools are selected to invest. Then the schools are ranked and the investment of US 50 million for 23 schools is allocated.

Performance Evaluation of China's Agricultural Listed Companies Based on DEA Model

In order to evaluate the performance of China's agricultural listed companies,we analyze the overall efficiency,pure technical efficiency and scale efficiency of China's agricultural listed companies on the basis of input-output data concerning 34 agricultural listed companies,using BCC model in data envelopment analysis ( DEA) model. Then we analyze input-output redundancy situation using the slack variable derived from the model. The results show that the overall efficiency of China's agricultural listed companies is good,and the gap in efficiency between sub-industries is small; there is significant difference in performance between listed companies engaged in the same sub-industry,and the reason for invalid DEA in companies within the industry is complex; total assets and asset-liability ratio are high,and the effective output is not fully realized. Finally corresponding recommendations are put forward for promoting the performance of agricultural listed companies as follows: strengthening brand awareness; promoting the level of production technology; adjusting the input structure; transforming the agricultural growth mode.

Application of a mixed DEA model to evaluate relative efficiency validity

Data envelopment analysis(DEA) model is widely used to evaluate the relative efficiency of producers. It is a kind of objective decision method with multiple indexes. However, the two basic models frequently used at present, the C2R model and the C2GS2 model have limitations when used alone,resulting in evaluations that are often unsatisfactory. In order to solve this problem, a mixed DEA model is built and is used to evaluate the validity of the business efficiency of listed companies. An explanation of how to use this mixed DEA model is offered and its feasibility is verified.

Evaluation of Urban Resource and Environmental Efficiency in China Based on the DEA Model

This paper illustrates the spatial variations in urban resource and environmental efficiency （REE） amongst 285 cities in China using a Data Envelopment Analysis （DEA） model, and examines the factors that have had the greatest effect on this spatial pattern by regression models. The results gave an average urban REE of 0.6381, and an average pure technical efifciency （PTE） and scale efifciency （SE） of 0.6964 and 0.9225, respectively. The results support the existence of a U-shaped relationship between REE and income level, which means that an increase in urban GDP does not result in an equivalent increase in environmental efficiency. Economic growth affects REE in three ways： scale effects （population scale and urbanization rate）; composition effects; and spatial effects. Improvements in urban resource use and environmental efifciency depend upon both technological innovation and effective governance. Policies designed to achieve these improvements should therefore be implemented at al levels of government and local enterprise.

基于SBM-DEA模型的江苏省碳排放效率研究

本文运用MaxDEA9软件,基于非期望产出的SBM-DEA模型和Malmquist指数法从静态和动态两个方面研究2010-2021年江苏省及其13个地级市的碳排放效率。结果表明,(1)江苏省的整体碳排放效率在2010-2021年间稳步增长,并且在2019年开始达到有效,在空间上呈现苏北大于苏南大于苏中的不均匀分布格局。(2)江苏省碳排放效率的平均增长速度呈现苏北大于苏中大于苏南的趋势。(3)江苏省及其13个地级市技术变化指数变动对碳排放效率增长有关键作用,碳排放效率各期增长速度受到当期技术发展水平的制约。

Regional Energy Efficiency in China Based on a Three-Stage DEA Model

Energy is the material basis for social development and is closely related with the economy. Energy shortage, a low utilization rate of energy and the deterioration of the environment have become the main restrictions of economic development in China. Therefore, studying energy efifciency has a practical signiifcance for developing a harmonious and sustainable energy economy and building a conservation-minded and harmonious society. Here, based on the three-stage DEA model we analyzed the energy efifciency of 29 provinces in China in 2009, set up an evaluation index system of energy efifciency to compare differences in energy efifciency among regions and provide regions with theoretical guidance to adjust energy consumption strategy and improve energy efifciency. We divided technical efifciency into pure technical efifciency and scale efifciency, analyzed energy efifciency with its numerical value and added environment variables to perfect the results. We found that scale efficiency is overestimated before eliminating external factors and environment variables and pure technical efifciency is underestimated. To solve this problem, regions should expand the scale of the enterprises and pay more attention to energy efifciency. The scale returns of most provinces in the third stage are increasing （except Shandong province）, which shows that many enterprises are too smal to relfect the economy scale. Therefore, al regions except Shandong should increase their energy inputs to obtain the economy scale of energy utilization. From a regional perspective, eastern energy efifciency is highest and western is the lowest. Al regions should increase the size of enterprises to realize the scale economy. Central and western regions in China should strengthen mutual cooperation, bring into play their respective advantages, exploit new energy and new technology and improve the utilization ratio of energy.

基于DEA模型的区域物流与应急管理协同发展测度——以京津冀地区为例

当今世界自然灾害、公共卫生事件、军事冲突等突发事件频发,对各地发展带来较大隐患。应急管理成为构建安全生产和社会稳定的坚实保障,而区域物流是应急管理实现的主要载体,科学评价两者协同程度,对推动区域可持续发展具有重要意义。该文以京津冀为例,运用DEA模型对2014—2023年区域物流与应急管理协同发展水平进行测度,二者之间的协同发展趋势呈现出阶段性波动趋势,后用Tobit回归模型测评影响两者协同发展效率的因素,结果表明:城市化进程和区位因素对二者的协同发展效率显著正相关,应急储备水平对京津冀区域物流与应急管理协同发展效率显著负相关,而产业结构和信息化水平均未达到显著性水平。该成果以期为优化区域物流与应急管理的协同策略提供参考依据。

基于三阶段DEA的农业能源效率计算方法改进

精准测算是提高农业能源效率的基础,有助于识别能源使用的瓶颈和潜力,优化农业能源结构,突破能源与环境双重约束,进而有力有效地推进乡村全面振兴。概念辨析发现,传统的农业能源效率测算结果实质是包含能源的农业生产效率。为科学合理地测算农业能源效率,本文提出了一种基于三阶段数据包络分析(DEA)模型的改进计算方法,并以中国30个省(自治区、直辖市,不包括香港地区、澳门地区、台湾地区和西藏)的面板数据为样本进行测算,对比原有方法的分析结果以验证改进方法的可靠性。结果表明:1)随机前沿(SFA)分析可知,环境变量和随机因素对能源效率影响显著,说明该方法能够剔除生产因素对农业能源效率的影响,从而规避部分测算结果高于实际值的问题;2)与传统方法对比,改进方法的估算结果与中国农业经济发展趋势更相符,波动节点与相应政策出台时间更契合;3)传统方法的估算结果会受物价和成本影响,与真实农业能源效率产生较大偏离,其中北京、上海和青海最为明显。综上所述,改进的三阶段DEA农业能源效率测算方法明显优于传统方法,可为企业及政府在农业节能减排方面提供更加准确的决策依据。

我国群众体育公共财政支出效率测度与评价——基于三阶段DEA-Malmquist指数模型的实证分析

基于现有群众体育公共财政支出绩效评价研究,采用三阶段DEA-Malmquist指数模型,探究2013—2021年我国31个省份群众体育公共财政支出的静态和动态效率。结果表明,环境因素对我国群众体育公共财政支出效率存在较大影响;剔除环境因素和随机扰动后,我国群众体育公共财政支出的综合效率有所提升,但仍受到规模效率的制约,存在一定的提升空间;地区间呈现出“东部>中部>西部”的异质性特征,各省份之间的综合效率差距较大;从Malmquist指数及其分解的动态变化来看,全要素生产率指数得到了优化,其中技术进步发挥了主要的促进作用。基于此,提出要加强资源统筹管理,打造多元协同主体,完善转移支付制度,提高预算信息化水平。

基于神经网络ODE和非线性MPC的DEA建模与控制

针对介电弹性体驱动器(Dielectric elastomer actuator,DEA)建模与控制的挑战性问题,提出基于神经网络常微分方程(Ordinary differential equation,ODE)和非线性模型预测控制(Model predictive control,MPC)的DEA动力学建模与跟踪控制方法.首先,基于神经网络ODE建立DEA的动力学模型以描述其复杂的动态行为.然后,基于所建立的DEA动力学模型,设计非线性模型预测控制器实现其跟踪控制目标.最后,在所搭建的实验平台上进行一系列跟踪控制实验.在所有实验结果中,DEA的运动均能很好地跟踪目标轨迹,且相对均方根误差均不超过3.30%,说明了所提动力学建模与跟踪控制方法的有效性.

基于两阶段DEA模型的江苏省动力电池行业回收效率评价研究

本文选取江苏省2014年至2023年30家动力电池回收企业的实际数据,通过构建DEA模型对这些行业的回收效率进行评价分析。研究结果表明:第一,近十年以来,江苏省动力电池回收行业的回收效率总体处于较低水平,还有很大的提高余地。第二,近十年以来,江苏省动力电池回收行业的配置效率处于不断提高阶段。

基于SBM-DEA和Malmquist模型的城市土地利用效率评价——以湖北省12个地级市为例

本文以湖北省12个地级市为研究对象,运用SBM-DEA模型和Malmquist指数模型对城市土地利用效率进行分析。研究结果表明:(1)2009-2019年湖北省12个地级市的土地利用效率均值为0.947,属于中上水平,其效率值每年不断波动,整体变动幅度稳定,但区域间差别较大;(2)技术进步指数和全要素生产率指数的增减方向和幅度基本保持一致,两者之间关联度较大,全要素生产率指数处于增长态势。

高职学生非认知技能培养效率评估——基于DEA-Tobit模型的测算

非认知技能对个体发展至关重要,提高高职院校非认知技能的培养效率有助于优化职业教育资源配置。利用2022年全国高职学生发展调查数据,采用超效率数据包络法(SE-DEA)测算了31所高职院校非认知技能培养的技术效率,并结合Tobit模型分析了高职学生非认知技能培养效率的影响因素。研究发现:25所高职院校的非认知技能培养的技术效率有效,且行业特色鲜明、专业集群化程度更高的学校技术效率表现更好;衡量学校过程性投入的教师教学热情变量对非认知技能培养效率有显著正向影响,而衡量学校资源投入的师资水平变量产生了消极影响;此外,专升本学生所占比重不利于学校整体的非认知技能培养效率。