农业社会化服务有助于提升农业绿色生产率吗？

从服务分工视角破解资源环境约束与农户行为的市场约束,探究农业社会化服务对农业绿色生产率的影响机制,旨在寻求实现农业可持续发展的可行路径。文章利用江西省9个县（市、区）34个村645个水稻种植农户抽样调查数据,构建非期望产出的SBM模型测算农业绿色生产率,同时采用Tobit模型检验农业社会化服务对农业绿色生产率的影响,并分析农户土地禀赋下的经营规模、土地细碎化、地块规模与农业社会化服务的交互作用。结果表明,样本农户的农业绿色生产率均值为0.48,仍处于较低水平;农业社会化服务对农业生产率具有显著的促进作用;伴随社会化服务参与程度的加深,即采纳社会化服务的农业生产环节越多,农户的农业绿色生产率水平越高;农户土地经营规模和地块规模的扩大,能够增强农业社会化服务对农业生产率的促进作用,而土地细碎化程度则会抑制这种促进效应。异质性分析发现,施肥服务和病虫害防治服务是促进农业绿色生产率提升的关键环节;进一步的机制分析发现,农业社会化服务通过诱导农户采纳农业绿色生产技术从而促进农业绿色生产率提升。据此,基于发展农业绿色生产,应促进农业社会化服务组织的发展与完善、引导农户开展适度土地规模经营,注重农户...     

农地富集区农地经营效率差异及影响因素 ——建档立卡农户与非建档立卡农户比较

研究目的：基于生计资本差异分析东北农地富集区建档立卡农户与非建档立卡农户农地经营效率差异及其影响因素,为巩固脱贫攻坚成果并向乡村振兴有效过渡提供参考。研究方法：DEA模型与Tobit模型。研究结果：（1）研究区农户农地经营效率偏低,建档立卡农户的综合技术效率与纯技术效率均显著低于非建档立卡农户,而农地经营效率差异主要是由二者的纯技术效率差异引起的;（2）建档立卡农户与非建档立卡农户均存在土地与资金投入冗余;（3）在生计资本差异下,样本农户总体、建档立卡农户、非建档立卡农户的农地经营效率主要受人力资本、自然资本、金融资本的影响。研究结论：应注重从农业技术应用、农业生产金融体系建立、新型农业经营主体培育等多方面着手提高农户农地经营效率。     

居民生态补偿支付意愿与支付水平影响因素分析——以黄河下游为例

文章以Probit、Tobit回归模型为主要工具,利用来自黄河流域下游山东省464份调查问卷的数据,研究了影响居民生态补偿的支付意愿与支付水平的主要因素。研究表明:影响居民生态补偿支付意愿与支付水平的因素并不完全相同。对生态环境问题的关注程度和性别因素显著影响居民的生态补偿支付意愿,但显著影响居民的生态补偿支付水平的因素是对黄河上游生态环境重要性的认识;另外,显著影响居民生态补偿支付意愿与支付水平的共同因素是对保护黄河上游生态环境需要大量投入的知晓程度和居民年收入。     

战略性新兴产业上市公司动态创新效率测度及其影响因素研究——基于两阶段DSBM模型与Tobit模型

以873家战略性新兴产业上市公司为研究对象,采用产出导向的DSBM模型测算两阶段整体和不同细分产业的动态创新效率。基于微观企业层面,分别以营业收入增长额、营业收入、营业收入增长率作为技术成果转化阶段的创新产出指标,测算并比较对应的创新效率。结果表明,以营业收入增长额作为创新产出更加符合实际情况,不同细分产业的创新效率存在异质性。进一步运用Tobit模型分析影响企业创新效率的因素发现,在技术研发阶段,企业规模、资产收益率、研发强度、劳动者素质、企业性质对创新效率具有正向影响,研发人员、研发资金、企业年龄、政府补贴对创新效率存在负向影响;在成果转化阶段,发明专利授权数、企业规模、资产收益率、研发强度、劳动者素质对创新效率具有正向影响,员工总数、研发支出、企业年龄、政府补贴、企业类型对创新效率存在负向影响。在创新驱动发展战略实施背景下,结论可为测度战略性新兴产业上市公司动态创新效率提供指导,为提高战略性新兴产业上市公司创新效率提供决策参考。     

我国中部六省节能减排效率测评及其影响因素分析——基于超效率DEA模型和Tobit模型

利用2010年我国中部六省的面板数据,运用投入导向的超效率DEA模型计算其2010年的节能减排效率值,然后采用Tobit模型对影响节能减排效率的各因素进行具体分析。结果表明:2010年中部六省中只有河南、湖北和湖南是节能减排DEA有效的决策单元;中部六省节能减排整体水平不高,节能减排潜力很大;各省的经济规模和排污费收入与节能减排效率存在明显的正相关关系,工业产值比重和煤炭资源储量与节能减排效率存在明显的负相关关系。     

R&D in Indian manufacturing enterprises: what shapes it?

The article examines the factors influencing research and development (R&D) in manufacturing entities. Using data on a large sample of companies for the period 1995–2007, the finding indicates that large companies have a higher probability of pursuing R&D, although with lower intensity. In terms of magnitudes, a 10% increase in firm size raises R&D intensity by roughly 0.6%. Both the intensity and the probability of undertaking R&D initially declines for older firms. Outward orientation, and especially foreign currency earnings, has a significant bearing on R&D efforts. R&D efforts are also found to vary significantly across firm ownership.     

Global public spending efficiency in Tuscan municipalities

The paper presents a Data Envelopment Analysis aimed at studying the efficiency of Tuscan municipalities' public expenditure. Five strategic functions of Tuscan municipalities are first considered carrying out a non-aggregate analysis; then the overall expenditure composition of each municipality and the global spending efficiency are analysed by a proposed composite indicator. The main determinants affecting the municipalities' efficiency were further investigated. In particular, the obtained results may be consistently included in the long-standing debate on the municipal size, proving that the bigger the municipality, the greater its level of public expenditure efficiency.     

Impact of off-farm labor supply on food expenditures of the farm household

Farm households diversify their income sources by working off the farm. This is a risk management strategy that is used by farm households in both developed and developing countries. Income diversification via off-farm work is associated with higher incomes and food consumption. However, little is known about the association between off-farm work and farm household food expenditures. In an effort to bridge this gap, this study attempts to assess the impact of off-farm work decisions by the operator and/or the spouse on the food expenditures of the farm household. Using a nationwide farm household survey in the United States and new econometric method, we find that the decisions of the operator and/or the spouse to work off the farm are significantly interrelated (29%). However, these two decisions affect food expenditures in different ways. The operator’s off-farm work decision is positively related to food expenditures, while the spouse’s decision is negatively associated with expenditures on food by the farm household.     

Use of quadratic terms in Type 2 Tobit models

A Type 2 Tobit model with a common set of regressors in the selection and regression equations is identified by the nonlinearity of the distribution function. The estimates are relatively less precise than in cases where there are at least some distinct regressors in the two equations. In an attempt to overcome this problem, some authors introduce quadratic terms into one or both equations. As this does not add any new statistical information, just a deterministic function of an existing regressor, the sceptic would question how this could improve the reliability of the estimates. This article shows that arbitrary use of quadratics is not without consequence. It increases the chances of getting either multiple roots, no root or a local root where a global does not exist. The nature of this problem is illustrated with Monte Carlo methods as well as several examples from the literature.     

The impact of national macro-environment exogenous variables on airport efficiency

Our paper tests the extent to which airport efficiency is affected by national macro-environmental factors. The literature on airport performance measurement is extensive but has tended to focus mainly on estimating the effects on efficiency from what are mostly endogenous variables. We undertake a two-stage analysis of 59 international airports observations in the Europe and Asia-Pacific regions. The first stage involves the use of Data Envelopment Analysis (DEA) to measure the efficiency of these airports. This is followed by a second stage, where we use a Truncated Regression model that incorporates the Simar and Wilson bootstrapping technique to test the extent to which a set of macro-environmental factors affect airport efficiency. Results reveal that a state's air transport sector output, institutional quality and robustness, the macro-economic environment, safety and security, and human development, all have a significant influence on the performance of airports. The result of this study fills the gap in the literature related to the non-discretionary variables affecting the performance of airports. It also suggests that policymakers and airport managers consider the identified factors when benchmarking airports.