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1.
完善创新生态系统、提升区域创新能力是我国科技企业孵化器建设的重要目标。基于2013-2018年中国(内地)30个省份面板数据,采用面板数据模型实证检验科技企业孵化器是否促进了区域创新能力提升,并基于中介效应模型探讨风险投资和孵化基金在其中的间接作用。结果发现:①科技企业孵化器建设显著提升了区域创新水平,但主要增加的是实用新型和外观设计专利申请授权数总量,对发明专利申请授权数并没有显著促进作用。上述结果在剔除直辖市样本、采用随机效应模型及空间计量模型的稳健性检验后依然成立;②通过中介效应模型检验发现,区域风险投资和孵化基金集聚效应是科技企业孵化器影响区域创新水平的主要机制;③科技企业孵化器对区域创新的影响在不同区域间差异较大,在东部地区的创新激励效应更加显著,而且政策工具强度对科技企业孵化器与区域创新水平的关系具有正向调节作用。  相似文献   
2.
We investigate contractors' bargaining power and holdup on buyers in procurement auctions of incomplete contracts held by California Department of Transportation. Using a model where contractors bid competitively in response to a buyer's choice of initial contract design, we infer the contractors' costs and bargaining power from the bids and transfers negotiated after the auction. We find that the contract winners have substantial bargaining power in post‐auction negotiation. The average holdup on the buyer is about 20% of project costs. Counterfactual cost‐plus contracts would reduce the buyer's surplus in 72% of the projects, with an average reduction over $382,000.  相似文献   
3.
The “industry nurturing agriculture” reforms and World Trade Organization accession led to dramatic growth in public expenditure and international trade in China’s agricultural sector. This article aims to estimate the effects of public expenditure and trade on agricultural productivity in China for 2004–2015. A semi-parametric production function with shape constraints is introduced to derive more accurate productivity before the productivity determinants are analyzed with an emphasis on public expenditure and trade. The empirical result shows that public expenditure and exports can effectively improve agricultural productivity, while imports have no significant effects. Policy implications are discussed in the context of supply-side reforms.  相似文献   
4.
[目的]深入分析江西省休闲农业示范点空间分布特征,进而可以提出促进区域休闲农业提升发展的对策建议。[方法]选取2010—2016年江西省国家级和省级休闲农业示范点作为数据,基于最邻近点指数、核密度估计法、不均衡指数和数量类型评价的方法,研究江西省休闲农业示范点的空间分布、类型构成与发展水平。[结果]江西休闲农业示范点空间上呈现聚集型分布特点,主要分布于中心城市、大型景区周边和交通干线沿线,以休闲农园、观光农园和生态农园等类型为主,存在空间分布不均衡、类型结构不合理等问题。[结论]以区域中心城市为中心,建设五大主题功能片区,优化多层级交通游线组织,加强城市、景区与农业资源丰富、生态环境优越区域的交通联系,并充分发挥休闲农业示范点的辐射带动作用,大力扶持培育休闲农业新业态,可以促进区域休闲农业的全面均衡发展。  相似文献   
5.
This article estimates the pass‐through rates between diesel fuel and retail milk prices at the product brand level. Using a random coefficient logit demand model and taking the direct and indirect impacts of energy prices, this research identifies changes in pass‐through rates before and after the great recession in 2008. Empirical results show that diesel prices significantly impacted the retail prices of milk products and are an important determinant of food price inflation. Pass‐through rates are estimated to range from 0.16 to approximately 0.60 through 2008 with an average of 0.22 for the whole period. Statistical tests indicate that pass‐through rates before June 2008 were significantly higher than after June 2008 when they dropped significantly to 0.04 to 0.17. Interestingly, private label brands have the lowest pass‐through rates, implying that compared to manufacturer brands, private label prices are more insulated from diesel price shocks.  相似文献   
6.
This study set out to evaluate the financing efficiency of low‐carbon companies. Applying a three‐stage data envelopment analysis with the data from 85 listed companies in China's low‐carbon industries over the period 2011 to 2017, this study has found that the overall financing efficiency of low‐carbon companies was relatively high, and the pure technical efficiency was quite steady over the period. The overall financing efficiency of these low‐carbon companies on average tended to change with the scale efficiency. This study has also shown that the scale efficiency was the main constraint influencing the financing efficiency of low‐carbon companies in China over the period. Our results are robust and have significant implications for policy makers and corporate managers.  相似文献   
7.
We developed and tested a research model in which employee well-being human resource (HR) attribution differentially influences the intention to change jobs across organizations (i.e., external job change intention) versus that within the same organization (i.e., internal job change intention). Furthermore, we posited that task idiosyncratic deals (I-deals) moderated the relationships between employee well-being HR attribution and external and internal job change intentions. Results indicated that employee well-being HR attribution was negatively related to external job change intention, but positively related to internal job change intention. Further, task I-deals significantly moderated the relationships between employee well-being HR attribution and external and internal job change intention. Specifically, employee well-being HR attribution played a less important role in reducing external job change intention when task I-deals were high rather than low. On the other hand, high task I-deals significantly strengthened the positive relationship between employee well-being HR attribution and internal job change intention. Our study extends the careers literature by differentiating the impact of employee well-being HR attribution on job change intentions within an organization compared with that across organizations and the important role of supervisors in enhancing or mitigating these effects.  相似文献   
8.
徐曼  唐瑞华  龚军 《现代食品》2020,2(4):158-160
本文探讨了面包酵母胞内甘油分析的预处理方法——微波破碎法。通过单因素实验分析,确定了胞内甘油的提取条件:酵母细胞用微波破碎3次、每次破碎10 s、间隔5 s,然后用10 mL蒸馏水提取30 min得到胞内甘油,此法简便、易提取,适用于天然产物的快速提取。  相似文献   
9.
高新技术企业认定政策是国家为扶持和鼓励高新技术企业发展而提出的一项重要政策,但其实施效果如何有待验证。采用2007、2010及2011年《中国工业企业数据库》数据,运用双重差模型对高新技术企业认定政策绩效进行评估。通过实证研究发现:①高新技术企业认定政策有助于提高企业市场价值及市场占有量;②高新技术企业认定政策对企业研发投入的增长影响不显著;③相对于中小型企业,高新技术企业认定政策对大型企业影响更大。最后,提出相应的政策建议,以期为我国高新技术企业认定政策完善提供启示。  相似文献   
10.
松嫩平原自然宜垦性及耕地后备资源开发潜力   总被引:1,自引:0,他引:1  
[目的]为保障我国粮食安全,为耕地后备资源的合理开发利用提供科学依据,同时完善中国区域耕地后备资源自然开发潜力方面的研究。[方法]文章从自然适宜性的角度出发,选取了地形、气候、土地类型和土壤4个方面15个评价因子,采用层次分析、专家打分等方法确定评价因子权重,构建松嫩平原宜垦性评价指标体系。[结果](1)1980—2015年松嫩平原自然宜垦性整体较好,最适宜垦区与较适宜垦区占松嫩平原面积的5068%,分布在松嫩平原腹地大部地区,中部、中北部、中南部等地;(2)松嫩平原已开垦耕地资源中,持续利用耕地占松嫩平原面积的4814%,空间上与宜垦程度高值区高度吻合;(3)新增耕地占区域面积的126%,以中度适宜垦区和较适宜垦区为主;(4)松嫩平原耕地后备资源占松嫩平原土地面积的1556%,在松嫩平原西部地区、中部和东北部地区均有分布,耕地后备资源中度及以上宜垦区占后备资源总量的7465%。[结论]目前大庆市和白城市可开发耕地后备资源最为丰富,但其中轻度及不适宜开垦区所占比例大,开发难度较大; 松原市可开发资源相对丰富且开垦难度小。  相似文献   
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