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1.
从效率差异视角构建国家创新影响力评价方法,揭示“一带一路”沿线国家创新要素流动倾向性以促进交流合作。运用DEA模型测算各国创新效率,根据DEA原理识别国家间的认可关系,构建创新网络并用节点特征向量中心度表示各国创新影响力,分析创新影响力类型、创新网络特征及创新投入冗余率与产出不足率。结果发现,各国创新效率存在显著差距;各国分别处于创新网络中心、核心和边缘位置,国家创新影响力依次递减;按照创新要素相对强度,沿线国家可分为6种创新类型;最后,提出沿线国家间开展创新交流与合作的必要性和途径。  相似文献   
2.
In recent decades, agricultural production in the U.S. has continued to shift to large-scale operations, raising concerns about the economic viability of small and midsized farms. To understand whether economies of size provided an incentive for the consolidation of production, the study estimates the total factor productivity (TFP) of five size classes of grain-producing farms in the U.S. Heartland (Corn Belt) region. Using quinquennial Agricultural Census data from 1982 to 2012 the study also compares TFP growth rates across farm sizes to gain insight into whether observed productivity differences are likely to persist. The finding of a strong positive relationship between farm size and TFP suggests that consolidation of production has contributed to recent aggregate productivity growth in the crop sector. The study estimates the extent to which sectoral productivity growth can be attributed to structural change versus other factors including technological change. The study also explores some tradeoffs associated with policies that raise the productivity of small versus large farms.  相似文献   
3.
在全面实施创新驱动发展战略的时代背景下,揭示中国高端装备制造业自主技术创新效率稳定性,测度相关因素的影响强度与方向,对揭示中国高端装备制造业自主技术创新规律,制定其发展策略具有重要指导意义。聚焦中国高端装备制造业自主技术创新效率稳定性及影响因素,采用DEA-Malmquist指数方法和Tobit回归模型进行实证研究,结果表明,中国高端装备制造业自主技术创新效率存在一定波动性,且各细分行业技术创新效率内部稳定性较差,产业自主技术创新效率整体稳定性不高;自主技术创新投入因素和环境影响因素对产业自主技术创新效率的影响具有较高的异质性,其中创新资金投入和人力资源投入对自主技术创新综合效率、纯技术效率及规模效率具有正向影响,而新产品开发投入和企业规模对自主技术创新综合效率、纯技术效率和规模效率的影响具有异质性,政策因素与市场因素分别具有显著和非显著负向影响,外源性创新因素具有显著正向影响,且影响强度较大。在此基础上,提出调整政府对高端装备制造业创新支持模式、加强外源性创新与智力引进等策略建议。  相似文献   
4.
《Business Horizons》2019,62(4):427-436
While financial reporting standards under U.S. GAAP and IFRS are fundamentally similar, differences do exist that may affect our analysis of company financial statements. This is particularly true when comparing a U.S. company following U.S. GAAP to a firm that uses IFRS. To illustrate, we compare research and development (R&D) accounting methods under both sets of standards and illustrate how they affect the analysis of financial results of firms in a specific industry—automotive manufacturers. Our results provide insight into settings in which differences in R&D accounting may have the greatest impact on financial analysis.  相似文献   
5.
研究目标:测算中国分行业的能源回弹效应与综合能耗系数。研究方法:通过编制含能源实物流量的价值型能源投入产出可比价序列表,测算出能源回弹效应与综合能耗系数,结合行业综合能耗情况分析了能源回弹效应的行业异质性。研究发现:各行业在能耗方面表现迥异,能源回弹效应也存在典型的行业异质性;中国整体经济能源回弹程度并不高,能效改善可以有效节约能源,但整体经济低能源回弹的表象也掩盖了部分行业能源效率无改善和高能耗行业高能源回弹的事实。研究创新:从系统与结构的视角审视了行业的综合能耗情况,并给出了一种基于能源投入产出表的能源回弹效应计算方法。研究价值:有助于提出整体经济结构优化与节能减排的行业政策。  相似文献   
6.
In this paper, we investigate the impact of oil prices on both aggregate and industry US real stock returns over the period 1973–2017. The empirical analysis contributes to the related literature introducing a state-dependent oil price (high and low) and the local projections approach. Our main finding is that, depending on the nature of the shock and industry, the negative effects of oil price shocks become exacerbated -and the positive effects get moderated- if oil prices are already high.  相似文献   
7.
I investigate the long-run relationship between corruption and innovative activity using annual data from 48 contiguous U.S. states between 1977 and 2006. Using U.S. data allows me to work with a panel long enough to exploit time series properties of the data. I use two different measures of innovative activity: one measuring the quantity and the other measuring the quality of the patents granted. I also use two different measures of corruption: one based on the number of corruption convictions, the other based on number of corruption stories covered in Associated Press news wires. Following Pedroni (1999, 2000), I estimate the cointegrating relationship between corruption and innovative activity with Fully Modified Ordinary Least Squares (FMOLS). The results indicate that corruption indeed slows down innovation in the long-run.  相似文献   
8.
吴丹  胡晶 《科技进步与对策》2018,35(20):128-136
科技创新规模扩张和科技创新效率提升是增强国家科技创新能力的两条关键途径。基于现有研究鲜有结合科技创新规模和科技创新效率开展国家科技创新能力评价的现状,采用因子分析法,系统筛选国家科技创新规模影响因素,并结合科技创新效率影响因素,完善国家科技创新能力评价指标体系,通过构建DEA Malmquist指数模型,评价不同时期国家科技创新效率变化指数,以及中国与全球10个国家科技创新能力的时空差异性。研究表明,R&D投入强度、R&D研究人员、专利申请量、科技期刊文章数、高科技产品出口额占制成品出口总额的百分比、科技创新效率是影响国家科技创新能力的关键指标;1991-2014年中国科技创新能力水平呈指数增长态势,有力提升了国家科技实力;全球10个国家科技创新能力水平除日本出现一定波动外,其余九国整体呈小幅递增态势。  相似文献   
9.
Research on productive efficiency at the firm level has developed as an important and active strand of research the last decades, both within operations research, management science and economics. Two apparently different definitions of efficiency are examined, but it is shown that when both estimation methods are based on solving linear programming problems the definitions of efficiency are identical. The purpose of the paper is to give the basic ideas of efficiency analyses using DEA as a tool for researchers not so familiar with efficiency analysis and DEA. The concept of shadow prices is given special attention.  相似文献   
10.
This article uses a multi-country global general equilibrium (GE) model to numerically simulate the effects of possible China–US trade wars. We introduce an endogenous trade imbalance structure with trade cost into the model which helps to explore both tariff and non-tariff trade war effects. Our simulation results show that China will be significantly hurt by the China–US trade war, but negative impacts are affordable. The US can gain under unilateral sanction measures to China, but will lose if China takes retaliation measures. Comparing the effects under mutual trade war, China will lose more than the US. Introducing non-tariff barrier trade wars will intensify the negative effects, and comparatively negative effects to China are larger than to the US. Mexico’s involvement in trade war with the US will strengthen the negative effects and comparatively hurt the US more. Under non-cooperative and cooperative Nash bargaining equilibrium, the US can gain more than China in trade war negotiation, which means the US has stronger bargaining power than China. Additionally, trade wars between China and the US will hurt most countries and the world especially in GDP and manufacturing employment, but benefit their welfare and trade.  相似文献   
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