中国农村减贫成效测度、分解及影响因素研究——基于分布动态学框架的CFPS数据分析

测算农村减贫成效并考察减贫成效的影响因素对我国打赢"脱贫攻坚战"具有重要的现实意义。本文基于覆盖我国东、中、西和东北四大地区的CFPS调查数据,在Quah(1997)的分布动态学(Distribution dynamics)基础上构建了完整的减贫成效分析框架。首先测算出各地区农村家庭贫困内部状态的Markov转移概率矩阵,并在此基础上构建了可分解的绝对、相对减贫指数,以综合考察各地区的农村减贫成效,随后本文通过首次构造的"条件Markov模型"进一步考察了减贫成效的影响因素。研究结果发现:(1)样本考察期内,我国各地区的农村贫困状况随着时间的积累逐渐变好,贫困发生率均有所下降;(2)减贫过程中仍存在着脱贫又返贫的现象,农村家庭的深度贫困固化问题比轻度贫困问题更加严重,意味着扶贫开发工作正式进入攻坚时期,扶贫难度加大;(3)家庭成年成员特征、家庭特征以及收入类型对农村减贫成效的影响显著性情况存在着时段和区域的异质性。其中,家庭成年成员受教育水平、家庭中是否有成员从事有薪酬的农业劳动、工资性和营业性收入对家庭的贫困状态变动具有更显著的影响。基于此,政府应贯彻落实精准扶贫,将扶贫重点放在中西部地区和处于深度贫困的家庭,另外应再调整和倾斜扶贫资源与扶贫政策,将提高农民受教育水平、增加非农业就业机会作为主要减贫途径,将促进农村工资性和营业性收入增长作为主要的政策倾斜方向。     

利益集团视角下的三农问题现状及对策研究

本文针对三农问题,首先运用集体行动理论,考察农民群体无法形成有竞争力的利益集团的原因：在此基础上通过建模构划出政府决策机制作为框架,对政府决策过程中力量悬殊的利益集团和群体之间的博弈结果进行分析;进而考察了现实中政府的城市偏向性政策形成的机理;最后从促成农民利益集团的形成、增强农民利益群体的力量和优化博弈三个角度提出政策建议。     

关于完全半解析函数的概念及性质的初步研究

给出完全半解析函数及其可调和的概念。讨论了线性性质及封闭性,研究了完全半解析函数的可调和性。得到了完全半解析函数的一些可调和条件,给出了完全半解析函数的构成。     

Feeding management of dairy cattle affect grassland dynamics in an alpine pasture

The effect of different supplementary feeding rates for grazing cattle on high-altitude pastures dynamics was evaluated. A field experiment was carried out during three years in a subalpine pasture area of the Eastern Alps. The investigated pasture area was 40?ha, located between 1820 and 2230?m?a.s.l. Two paddocks were chosen in the experiment and two herds of 12 cattle each were kept in the two enclosures for 5 weeks. For the first herd (HS), the supplementary feeding rate was 4.8?kg?OM?head^?1 per day, while for the second herd (LS), the rate was 1.6?kg?OM?head^?1 per day. The amount of herbage consumed by each cattle was determined using the n-alkane technique. To monitor the pasture vegetation dynamics, eight metal exclusion cages were placed in each paddock to determine herbage growth, utilization rates, vegetation composition and animal grazing selectivity. Grazing behaviour of dairy cattle, in terms of herbage intake and species selection was affected by the different feeding rates. Cattle grazing Paddock HS consumed 1.9?kg?OM?day^?1 of herbage less than Paddock LS. In the LS paddock, cattle grazed higher phytomass rates. When the animals were fed by higher concentrate rates, a more selective grazing seemed to significantly increase the pasture necromass component. The lower grazing selectivity favoured the development of species as Nardus stricta and Deschampsia caespitosa, which are well known for their low palatability. Distinct vegetation dynamic patterns were observed, with a reduction of hair grass and an increase of legumes in the Paddock LS.     

“主体-技术”协同视角下的战略性新兴产业创新网络分类研究——以新能源汽车产业为例

本文以“主体-技术”协同视角来分析战略性新兴产业创新网络形成的内在机理和分类模式。在结合2-模网络理论基础上,从核心技术和创新主体两个维度出发,将战略性新兴产业创新网络分为单核心实验室型、单核心产业链型、单核心辅助型、单核心复合型、多核心实验室型、多核心产业链型、多核心辅助型和多核心复合型。同时,以中国新能源汽车产业为例,通过实证分析发现：除了单核心辅助型和多核心辅助型之外,其它6种模式均存在,并进一步对其创新网络的分类模式及相关特征进行了全面分析。     

On Crop Biodiversity, Risk Exposure, and Food Security in the Highlands of Ethiopia

This paper investigates the effects of crop genetic diversity on farm productivity and production risk in the highlands of Ethiopia. Using a moment-based approach, the analysis uses a stochastic production function capturing mean, variance, and skewness effects. Welfare implications of diversity are evaluated using a certainty equivalent, measured as expected income minus a risk premium (reflecting the cost of risk). We find that the effect of diversity on skewness dominates its effect on variance, meaning that diversity reduces the cost of risk. The analysis also shows that the beneficial effects of diversity become of greater value in degraded land.     

Measuring Farm and Market Level Economic Impacts of Improved Maize Production Technologies in Ethiopia: Evidence from Panel Data

While it is often recognised that agricultural technology adoption decisions are intertwined and best characterised by multivariate models, typical approaches to examining adoption and impacts of agricultural technology have focused on single technology adoption choice and ignored interdependence among technologies. We examine farm‐ and market‐level impacts of multiple technology adoption choices using comprehensive household survey data collected in 2010/11 and 2012/13 in Ethiopia. Economic surplus analysis combined with panel data switching endogenous regression models are used to compute the supply shift parameter (K‐shift parameter), while at the same time controlling for the endogeneity inherent in agricultural technology adoption among farmers. We find that our improved technology set choices have significant impacts on farm‐level maize yield and maize production costs, where the greatest effect appears to be generated when various technologies are combined. The change in maize yield and production costs results in an average 26.4% cost reduction per kilogram of maize output (the K‐shift parameter). This increases the producer and consumer surpluses by US$ 140 and US$ 105 million per annum, respectively. These changes in economic surplus help to reduce the number of poor people by an estimated 788 thousand per year. We conclude that deliberate extension efforts and other policies that encourage integration of technologies are important for maize technologies to yield their full potential at both farm and market levels.     

基于面源污染约束的油菜生产效率时空变化及成因分析

[目的]分析面源污染约束条件下我国油菜生产效率的动态变化、省际差异及其影响因素,提出提升途径。[方法]采用基于非期望产出的非径向、非角度的数据包络分析模型测算面源污染约束下的油菜生产效率,根据投入冗余、期望产出不足或非期望产出冗余等,分析效率损失成因。[结果]我国油菜生产效率总体上呈现"N型"年际变化特征,其中黄淮区、江浙、重庆、青海和甘肃的油菜生产效率均值高于0.9,云贵和内蒙古的油菜生产效率则低于0.8。全国和长江流域省际差异表现为先扩大后缩小趋势,西北区省际差异最大,黄淮区省际差异最小。总氮和总磷排放量过高是长江流域乃至全国油菜生产效率损失的主要原因。近3年总氮可缩减比例均值大于30%的地区从大到小依次为湖南、内蒙古、贵州、云南和江西,总磷可缩减比例均值大于30%的地区依次为云南、贵州、四川和内蒙古。此外,湖北用工投入冗余、内蒙古化肥投入冗余和单产不足也是其油菜生产效率损失的重要原因。[结论]长江流域需重点削减氮磷径流损失,黄淮区应重点控制氮磷淋溶损失,西北区应重点治理氮磷侵蚀流失。     

ICT diffusion in public administrations and business dynamics: Evidence from Italian municipalities

Public administrations have been adopting information and communication technologies (ICT) to transform their internal organization and provide better public services to citizens and firms. However, the external benefits, despite being deemed relevant, have been empirically overlooked. We first explore the relation between ICT diffusion in public administrations and business demography at the municipal level by studying the Italian context. Our results show that ICT diffusion in the PA contributes to significantly reducing the death rate of firms and boosting their turnover rate. The adoption of ICT in the PA also exerts a positive impact on the firm birth rate, although it is not statistically significant. These results shed light on the importance of promoting e-government and framing coherent digital agendas as public instruments for supporting entrepreneurship and regional economic development.     

创新价值链视角下的区域创新活动收敛分析

基于创新价值链视角,将我国创新活动分为知识创新、科研创新、产品转化创新3个阶段,运用空间面板收敛模型对各类创新活动进行收敛检验,研究结果显示：①空间自回归因子和扰动项的空间滞后因子对创新增长率有显著正向影响,说明创新水平增长在地区间具有显著的空间效应,存在空间示范效应和外生冲击传递效应,同时空间面板模型拟合效果整体上优于普通面板模型,说明我国创新活动收敛中有必要考虑空间因素;②知识创新和知识转化创新水平存在稳定的绝对β收敛,科研创新水平不存在收敛,通过基尼系数时序图验证了我国科研创新活动存在“马太效应”,另外两类创新活动水平则朝着收敛的趋势发展;③高校资源、市场化水平分别对知识创新和产品转化创新收敛有显著促进作用,信息化水平对三大创新活动收敛都有显著的促进作用。