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.

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 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.

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.

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.

基于DEA模型的安康市农业投入产出效率评价

为了解安康市现代农业发展效率状况,选取2009—2020年安康市污染治理投资总额、农业固定资产投资额、耕地面积和乡村劳动力资源总数4个农业投入指标,以及农业总产值和农业人均生产值2个农业产出指标,采用数据包络分析(data envelopment analysis,DEA)模型中的BCC模型进行效率分析。结果表明,安康市农业投入产出效率只有2020年的DEA模型是有效的,但从2009年开始,综合效率总体呈现上升趋势;从投入冗余率与产出不足率可以看出,安康市农业总产值基本不存在产出不足的现象,除2020年外,其余各年份在污染治理投资总额、农业固定资产投资额、耕地面积和乡村劳动力资源总数的投入在不同程度都存在冗余,投入结构不合理造成DEA模型无效。

基于DEA-Malmquist模型的地方高校科技成果转化效率时空演变

通过构建DEA-Malmquist模型,实证分析了中国地方高校2012—2021年科技成果转化的技术效率和全要素生产率的时空演变特征.研究结果显示,中国地方高校科技成果转化的综合技术效率逐年提升,但2017年和2018年出现了显著下滑,且效率指数整体偏低;科技成果转化的全要素生产率整体有所提升,但区域差异显著,中东部地区发展平稳,西部地区波动较大.为了进一步提升地方高校科技成果转化的效率,提出了强化学科建设质量、明确科技创新定位、创新转化体制机制和优化成果转化环境等建议.

基于三阶段DEA的我国公共服务效率评价

采用三阶段DEA方法,选取2012—2021年我国公共服务的相关数据,分析政治社会类、经济发展类和文化建设类公共服务的效率状况.研究表明,剔除环境和随机因素的影响后,2012—2021年我国公共服务供给效率总体呈现上升趋势,外部因素对我国公共服务效率存在显著影响,各个省域都发生了不同程度的变化,其中对政治社会类公共服务和西部地区的影响最大.同第一阶段DEA结果比较,第三阶段的结果更加符合实际情况.据此,未来我国公共服务的政策重点有三:一要强化制度保障,炼就有制可循的“定心丸”;二要盘活创新要素,激发发展活力的“催化剂”;三要健全评价体系,擦亮效率监督的“监控器”.

考虑减排潜力的中国省域碳排放权分配研究——基于改进的ZSG-DEA模型

在2030年中国实现碳达峰的目标背景下,本文针对碳排放权合理分配的问题,采用改进的ZSG-DEA模型考虑各省(区、市)的减排潜力,探寻兼顾公平和效率的碳排放权省域分配方案。研究结果表明:(1)我国各区域减排潜力各不相同,东部地区减排潜力较大,西部地区减排潜力组内差距较大,且低减排潜力组有50%集中在西部地区,中部地区整体减排潜力不足,东北地区集中于中、低减排潜力组;(2)改进的ZSG-DEA模型计算出减排系数更加合理,缩减了减排压力差距,能通过缩小省(区、市)之间的不公平程度来降低政策实施难度;(3)综合减排潜力和减排系数两个方面发现,仍有部分省(区、市)如河南等处于低潜力高减排的状态,面临凭借自身条件难以有效降碳的困境,也有部分地区在碳减排方面“仍有余力”。基于上述结论,本文提出以下建议:各区域应发挥自身优势助力碳减排,在安排省(区、市)碳排放额度时要注重不同省(区、市)的减排潜力,同时加强减排责任意识,推动区域之间的合作。

光伏发电企业运营效率及影响因素研究——基于DEA-Malmquist-Tobit模型的分析

在“双碳”目标的引领下,科学评价光伏发电企业的运营效率及其影响因素,对促进光伏企业及产业的高质量发展有着重要意义。基于2014—2022年光伏发电上市公司的面板数据,运用DEA-Malmquist-Tobit模型测度了光伏企业的运营效率及其综合效率的动态变化,实证分析了运营效率的主要影响因素。结果表明,9年间光伏发电企业的全要素生产率呈1.8%增长率的小幅增长趋势,股权结构、每股收益等5个变量对光伏发电企业的运营效率有显著性影响。

我国养老机构服务效率测度及提升路径研究——基于三阶段DEA和Malmquist指数的实证分析

科学评估养老机构服务效率是优化养老资源配置和完善养老服务体系建设的基础。以我国29个省(区、市)为研究对象,基于2018—2022年《中国民政统计年鉴》和《中国统计年鉴》的数据,运用三阶段DEA模型和Malmquist指数模型,对养老机构服务的静态与动态效率测度进行分析。研究表明,养老机构服务效率逐年提升,但仍有改善空间。综合技术效率均值由0.794下降到0.726,受到外部环境因素的影响;技术进步是制约养老机构服务效率的主要原因。因此,要调整投入生产规模,重视环境因素影响,实施差异化的效率提升策略,以技术进步为发展重心,进而提高养老机构服务效率。

福建省专利质量对海洋技术创新效率的影响——基于DEA-Tobit模型的实证研究

海洋技术创新是推动海洋经济转型升级、提升海洋经济高质量发展的重要驱动力,如何提升海洋技术创新效率是当前面临的重要问题。为探讨专利质量是否影响海洋技术创新效率的提升,本文基于2007-2021年海洋统计数据,运用二阶段DEA模型测算福建省海洋技术创新效率,综合分析海洋科技研发效率和科技成果转化效率,进一步分析专利质量对海洋技术创新效率的影响。研究结果表明:2007-2021年福建省海洋技术创新整体效率较高,呈上升趋势;分阶段看,海洋科技研发效率总体平均水平低于科技成果转化效率。Tobit模型回归结果表明专利质量的提高对海洋技术创新整体效率及分阶段的研发效率和成果转化效率的提升均具有促进作用。此外,海洋经济规模、海洋产业结构、科研平台数、科研院校专利占比等因素对海洋技术创新效率也具有一定的影响。

基于DEA的绿色物流产业效能的评价

为评价双碳背景下的绿色物流产业效能并探索效能提升路径,采用DEA三阶段模型,以湖南省物流数据为研究样本,从科技角度选择创新发展指标,从三大产业与经济协调发展角度选取协调发展水平指标,从生态环境保护与减轻碳排放角度选取绿色发展指标,构建了绿色物流产业评价指标体系。评价结果表明:(1)湖南省的地级市之间绿色物流产业效能存在显著差异,环境因素对效能的影响较为明显,不同地级市之间的影响程度不同。(2)政府支持力度越大,投入冗余越少,越有利于绿色物流规模效益的形成;研发支出越多越有利于减少资源浪费,进而提高绿色物流产业效能。(3)DEA调整后由于技术性能的提升导致综合性能的变化,而技术性能又受外部环境和随机误差的影响。根据研究结果,从资源合理配置视角,提出湖南省绿色物流产业效能提升的路径。

海南自贸港上市公司融资效率的影响因素研究——基于DEA-Tobit模型

发挥资本市场支持海南自贸港高质量发展的作用,提高上市公司质量,需要重点解决好上市公司融资效率问题。以2018—2022年20家海南自贸港上市公司为研究样本,运用DEA-Tobit模型对它们的融资效率进行静态和动态分析,研究影响融资效率的因素,结果显示:海南自贸港上市公司的融资效率整体处于较低水平,但呈上升趋势,主要得益于技术进步;宏观经济因素、股权结构和企业成长能力等对融资效率的影响不明显。海南自贸港上市公司可通过强化上市公司管理水平及创新能力,提升上市公司财务管理水平,重视人才与科技的作用,牢抓全面注册制改革发展机遇,加快推进资本市场改革与开放等措施提高融资效率。

基于DEA模型的风电企业融资效率影响因素分析

基于“双碳”背景,利用我国31家风电企业的财务数据,借助DEA-Malmquist模型研究了2015—2022年风电行业静态与动态融资效率,发现近半数企业仍处于低效率区间;使用Tobit模型对各融资效率影响因素进行回归分析,发现资产周转率、净资产收益率等有正向显著影响作用,资产负债率等有负向影响作用。企业在日常生产经营过程中应关注政策导向,注意自身资产结构并加大科研投入以提高融资效率。

基于三阶段DEA-Malmquist指数模型的“十三五”时期新疆畜牧业经济发展效率特征

为了测算和提高新疆畜牧业经济发展效率,采用三阶段DEA-Malmquist指数模型,对“十三五”时期新疆14个地(州、市)畜牧业经济发展水平进行投入产出效率分析。结果表明,从静态分析来看,只有伊犁州直属县(市)在“十三五”时期的规模报酬不变,呈DEA有效;其他地区由于规模效率或纯技术效率下降导致综合技术效率呈DEA无效,规模大多递增。从动态分析来看,“十三五”时期Malmquist指数小于1.000,表明新疆畜牧业经济效率呈下降趋势,且技术进步的变动是阻碍畜牧业经济效率提升的主要原因。应加强技术管理力度,以新型牧业经营主体为导向,提高优化资源配置效率的能力;加强草原保护建设,推行适度规模。效率水平高的地区应保持畜牧业经济发展优势,进行技术推广;效率水平低的地区需从政策、登记体系、基础配套设施建设、人才、技术等方面加大投入。