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31.
China’s research and development (R&D) policy has changed considerably over recent decades, and great changes occurred in 2006 when the main programme objective of China’s R&D changed from the 863 Programme and 973 Programme to the National Science and Technology Major Project. One topic that has drawn extensive attention is whether the investment reform improved R&D productivity in China. Using a unique panel dataset from 160 universities, this paper examines the effect of the investment reform on productivity improvement in China’s agricultural biotechnology sector. We use a panel count data model with a dynamic feedback mechanism to model the knowledge production process. Strong evidence indicates that the investment reform greatly contributes to knowledge output production in China’s agricultural biotechnology sector. We also find that the input quality is more important than the absolute quantity; human research capacity exhibits the greatest contribution to the output of patents; past knowledge accumulation helps produce more patents; and entry barriers to patent production exist in China’s agricultural biotechnology sector. Moreover, the patent explosion in China may have been largely caused by improvements in the human capital input quality.  相似文献   
32.
The tidal river management (TRM) approach is an indigenous management practice in the Southwest part of the Ganges-Brahmaputra delta in Bangladesh. This approach has a high potential for extending area under agriculture with a positive impact on sustainable production and consequently on sustainable land use planning. Until recently, no studies provide a quantitative assessment on agricultural benefits of TRM operation. In this study, we aim to assess the benefits of TRM operation by using innovative approaches such as comparing land use change, agricultural production and economic cost-benefit analysis for two scenarios (with and without TRM) in the Hari-Teka-Bhadra catchment. We found that the financial benefit of TRM operation was 85.5 million US dollar per year from the agriculture sector. The results are useful for promoting land use policy through TRM approach in achieving greater sustainability in the area.  相似文献   
33.
本文基于动态分工演进,以自给自足的自然经济为起点,将秩序服务和财税政策纳入一个理论框架,结合超边际决策分析和一般均衡分析,考察在此过程中各个经济人的最优决策在市场上相互作用而内生的各种变化,揭示了财税政策作用于工农业分工和农业生产率的内在机制。然后,使用中国改革开放以来的数据对相关结论进行实证检验。模型分析表明,政府财税政策的实施在促进工农业分工水平提高的情况下,会扩大粮食生产的迂回化经济程度,进而推动粮食部门的农地生产率提升。就长期而言,单位面积的财政支农支出对农地生产率的提高有显著正向影响,在其他农业生产要素既定情况下,单位面积的财政支农支出每增加1%,农地生产率增加3.23%;从短期来看,单位面积财政支农支出对农地生产率的作用较弱,但在反向修正机制的作用下,最终会达到有效提高农地生产率的长期稳定均衡。另外,财政支农支出的增加促进了分工水平的提高,而分工水平的提高又推动了农业生产率的提升。  相似文献   
34.
Given the marked heterogeneous conditions in smallholder agriculture in Sub-Saharan Africa, there is a growing policy interest in site-specific extension advice and the use of digital extension tools to provide site-specific information. Empirical ex-ante studies on the design of digital extension tools and their use are rare. Using data from a choice experiment in Nigeria, we elicit and analyze the preferences of extension agents for major design features of ICT-enabled decision support tools (DSTs) aimed at site-specific nutrient management extension advice. We estimate different models, including mixed logit, latent class and attribute non-attendance models. We find that extension agents are generally willing to use such DSTs and prefer a DST with a more user-friendly interface that requires less time to generate results. We also find that preferences are heterogeneous: some extension agents care more about the effectiveness-related features of DSTs, such as information accuracy and level of detail, while others prioritise practical features, such as tool platform, language and interface ease-of-use. Recognising and accommodating such preference differences may facilitate the adoption of DSTs by extension agents and thus enhance the scope for such tools to impact the agricultural production decisions of farmers.  相似文献   
35.
农业减量化:农户经营的规模逻辑及其证据   总被引:7,自引:0,他引:7  
本文将农户分为五种类型,并将农地规模分解为地块规模、经营规模与连片规模,由此构建“农户类型—规模形式—减量化行为”的分析框架,进而阐明农户减量化的规模逻辑。基于农户问卷的实证分析表明:①对于所有样本农户来说,地块规模越大,减施量越高。其中,追求产量最大化的生产型小农,减施量与经营规模呈“倒U”型变化,而追求多元化经营的功能型小农,减施量随经营规模的扩大而增加;②农户连片规模扩大,减施量就增高,并且能够增强地块规模扩大以及经营规模扩大对减施的促进作用;③农户社会服务卷入程度加深,能够增强地块规模、经营规模和连片规模扩大对减施的促进作用。据此,农业减量化,应鼓励农户开展连片种植,形成生产性服务的市场容量,然后诱导服务供应商提供专业化服务,进而实现服务规模经营对农地规模经营的替代。  相似文献   
36.
现运用面板回归模型结合产值贡献度的方法评价了新疆农村产业融合度,结果表明,新疆农业与农产品加工业融合度、农业与农业服务业融合度均较低。通过地理信息可视化表达发现,新疆农村产业融合度且存在明显的区域差异。最后,结合新疆农村产业融合发展所面临的困境,提出了需要完善农业教育服务体系;培育区域特色品牌;加强对各种利益联结方式的监督引导等建议。  相似文献   
37.
"健康中国"战略背景下,准确估算健康资本折旧率对把握我国人口健康资本动态变化具有重要意义。在经典的健康资本需求框架内,正式引入年龄、环境与健康投资的异质性,扩展构建健康资本内生折旧率模型。基于永续盘存法基本原理,结合精算模型与生命表数据,对不同年龄、性别和风险假设下我国居民健康资本折旧率进行估算与分析。研究发现,我国居民健康资本折旧率存在明显的年龄差异与性别差异:中青年阶段折旧率缓慢提高、老年阶段加速上升;男性健康资本折旧率始终高于女性。随着人口老龄化程度加深,年龄对健康资本折旧率的影响下降,健康投资的影响则持续增强。提高健康投资回报率,是降低折旧率进而提高我国人均健康资本存量的关键。  相似文献   
38.
The number of Irish dairy farms with herds greater than 100 cows has increased from 4.5 % in 2005 to 23 % in 2016. The abolition of the dairy quota in 2015 has led to predictions that this trend will continue and that an additional 6000 people will be required to work on dairy farms by 2025. Ownership of farms is esteemed, with farm employment perceived as a poor second option, so it is necessary to identify possible routes towards creating 'good' farm employment relationships. This paper explores the social, cultural and economic values of employers and employees in the context of early experiences of farm employment in post-quota Ireland. Using narrative analysis, this study found that employees gained esteem and pride from acquiring managerial responsibilities and receiving recognition for their abilities and accomplishments from their employers. Greater social recognition of employ’ abilities by peer groups and in networks (social capital) cemented ‘good employee’ status. Employers, in a context of unprecedented dairy production expansion, emphasised the need for and demonstrated changing of power structures to open up the farm to new forms of influence. However, employers’ reflexivity in support of employment relationships was undermined overall by what the management literature calls a weak ‘rewards system’ for employees. Without the supportive scaffolding of a formalised rewards system, relational gestures of responsibility-devolution and employ’ appreciation of employees may be insufficient to sustain quality farm management employment in the long term. Inevitably, this diminishes the attractiveness of farm employment, limiting the drawing of talent not only into farm employment but into associated capacity-building programmes.  相似文献   
39.
The issue of what to promote in total factor productivity (TFP) in urban areas has been widely discussed in academia and housing prices and population density are confirmed to be two of the most essential driving factors. However, research into the interaction of housing prices and population density with TFP has been neglected, with no previous studies taking spatial factors into consideration, which may bias the results. From this perspective, using spatial panel data models and employing instrumental variables to solve the endogenous problem, this study examines the impact of housing prices on TFP through the mediating effect of population density for 283 Chinese cities during the period 2000–2013, and confirms that the mediating effect accounts for 18.70 % of the total effect. The results show the positive and significant association of housing prices with TFP and the inverted U-shape of population density. The underlying logic is that housing prices change population density by attracting people with high purchasing power and discouraging those unable to afford housing, whereas increased density helps to promote productivity since the settled inhabitants always have highly developed work skills and are well educated. The influencing mechanism of housing prices on TFP through population density is analyzed, namely the spillover effect. We find that the spillover effect exists in the eastern and central regions, as well as first, second, and third tier cities, while for western regions and fifth tier cities, population mobility and increased in housing prices slows their economic development. There is no evidence of any spillover effect in fourth tier cities. A discussion and suggested policy implications are also provided.  相似文献   
40.
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