互联网发展、技术市场与高技术产业技术创新效率——基于SBM-熵权-Tobit模型的实证检验

以技术市场发展指标作为中介变量,构建互联网发展对技术创新效率的面板回归模型,实证检验互联网发展对高技术产业技术创新带来的直接和间接影响效果。结果表明：(1)2009—2019年,技术创新效率在[0.1932,0.4043]内,且上升趋势明显,成果转化阶段效率明显高于知识生产阶段;(2)从理论方面推导互联网发展对于技术创新效率的直接影响,以及通过技术市场厚度和流畅度两种中介路径的间接影响,提出假设1～假设3;(3)实证结果表明,三个理论假设在研究样本中均成立。互联网快速发展不仅对高技术产业的技术创新效率具有直接的正向驱动效应,而且通过市场厚度和市场流畅度两个中介变量产生的间接效应均显著为正值。在东中西三个经济区,表现出明显的异质性。“互联网+技术市场”战略是提升高技术产业创新资源优化布局发展的重要方向。     

关于农业剩余劳动力转移的几点认识

改革开放以来,农村劳动力呈现出从最初的就近转移到跨区域和梯度转移,这种大规模的人口流动过程对中国的经 济增长以及农村经济的繁荣曾经产生较大的影响,并孕育着新的契机。本文计算了农村剩余劳动力转移对经济增长的贡献, 并从正反两方面,论述了1991-2002年农村剩余劳动力转移对于农业乡镇企业以及经济增长的贡献。     

How much are electric vehicles driven?

The prospect for electric vehicles as a climate change solution hinges on their ability to reduce gasoline consumption. But this depends on how many miles electric vehicles are driven and on how many miles would have otherwise been driven in gasoline-powered vehicles. Using newly-available U.S. nationally representative data, this paper finds that electric vehicles are driven considerably fewer miles per year on average than gasoline-powered vehicles. The difference is highly statistically significant and holds for both all-electric and plug-in hybrid vehicles, for both single- and multiple-vehicle households, and both inside and outside California. The paper discusses potential explanations and policy implications. Overall, the evidence suggests that today’s electric vehicles imply smaller environmental benefits than previously believed.     

Does economic growth and energy consumption drive environmental degradation in China’s 31 provinces? New evidence from a spatial econometric perspective

The panel data analysis points to economic and social factors contributing to NO_x, PM_2.5, PM₁₀, SO₂, and VOCs in China’s 31 provinces. The spatial correlation analysis using Global and Local Moran’s I values indicates the existence of a significant and positive spatial autocorrelation with respect to environment, economy and energy, and the high spatial correlation is evident in the eastern region, covering the northern part of Yangtze River Delta, Huaihai Economic Zone, and the lower reaches of the Yellow River Economic Belt. The empirical estimation is performed through spatial lag and spatial Durbin models. All emitted air pollutants in 31 provinces have significant spatial dependence and strong spillover effects. There is an inverted U-shaped relationship between emitted air pollutants (NO_x, PM₁₀, VOCs, and PM_2.5) and per capita GDP, which follows the EKC hypothesis. The relationship between SO₂ and per capita GDP does not follow the EKC hypothesis. There is a positive relationship between pollutant emissions and coal consumption, which is consistent with current studies for various countries like Canada, Denmark, UK and US and regions like New York State. However, the effects of science and technology investment on air pollutants are mostly positive, which is not as policy expected.     

Dynastic Inequality Compared: Multigenerational Mobility in the United States,the United Kingdom,and Germany

Using harmonized household survey data, we analyze long‐run social mobility in the United States, the United Kingdom, and Germany, and test recent theories of multigenerational persistence of socioeconomic status. In this country comparison setting, we find evidence against a universal law of social mobility. Our results show that the long‐run persistence of socioeconomic status and the validity of a first‐order Markov chain in the intergenerational transmission of human capital is country‐specific. Furthermore, we find that the direct and independent effect of grandparents' social status on grandchildren's status tends to vary by gender and institutional context.     

中国海洋渔业空间生态格局探究——以我国沿海11个省市为例

海洋渔业是我国海洋强国的重要组成部分,但近年来全球气候变暖、海域环境污染等严重的资源问题和生态问题日益对我国海洋渔业生态文明建设提出新的挑战。本文选取 2006-2016年我国沿海11个省市海洋渔业相关面板数据,首先将海洋渔业二氧化碳排放量作为非期望产出纳入超效率 SBM-DEA窗口分析法中,测算出海洋渔业生态效率值并评价其有效性。然后进一步探究海洋渔业生态效率的空间效应并运用Tobit随机效应面板模型,分析了海洋渔业生态效率的影响因素。结果显示：（1）我国沿海 11个省市海洋渔业生态效率有效水平较低且存在区域差异。（2）我国 沿海 11个省市海洋渔业生态效率水平逐步由随机相异发展空间格局向聚集态势变动。（3）我国沿海 11个省市的海洋渔业经济发展水平对海洋渔业生态效率的影响呈现出显著的负相关关系;渔业产业结构、海洋环境政策与海洋渔业生态效率的影响呈现出 正相关关系。最后基于实证研究,提出建设海洋生态渔业,提升海洋渔业生态效率有效水平的建议。     

产业集聚、资源错配与环境治理的协同效应分析

解决经济增长与环境污染之间的矛盾是新时期我国经济发展过程中的重要任务,产业分散以及资源错配被认为是助长环境污染的重要诱因。论文基于2010—2018年省级面板数据,实证检验了产业集聚、资源错配与环境污染之间的关系,研究结果表明:整体来看产业集聚会减少污染物的排放,但在产业发展初期,集聚在一定程度上会增加污染物的排放;资源错配与污染物排放显著负相关,经过一系列稳健性检验,这一结论仍然成立;产业集聚有利于减少资源错配,提高资源分配效率,从而减少环境污染,产业集聚与资源配置在环境治理过程中会产生正向协同效应。     

金融科技与上市商业银行全要素生产率的研究——基于三阶段SBM-DEA模型

本文运用基于非径向和非角度及包含非期望产出的三阶段SBM-DEA模型三阶段对我国28家上市商业银行2009—2018年的全要素生产率进行了测算和分析,并依据国有商业银行、股份制银行和城市商业银行属性进行异质性分析。同时使用固定效应模型对金融科技对银行全要素生产率的影响进行实证分析。研究结果表明：(1)商业银行金融科技的发展对上市银行全要素生产率有明显正向促进作用,主要的作用路径是通过促进商业银行产品与服务上的创新;(2)相较于城市商业银行,这种促进作用对国有银行和大型商业银行表现更大,尤其是大型商业银行;(3)效率分解为纯技术效率和规模效率后,商业银行金融科技的发展对银行纯技术效率的提升有正向促进作用,说明金融科技的发展对银行全要素生产率的作用更多表现在技术进步方面。     

健脾调肝法治疗2型糖尿病胃肠功能紊乱患者的临床价值

目的探讨常规西药联合健脾调肝法治疗2型糖尿病胃肠功能紊乱患者的临床价值。方法选取2019年3月至2021年1月盘锦市人民医院收治的102例2型糖尿病胃肠功能紊乱患者作为研究对象,按随机数字表法分为对照组与观察组,各51例。对照组患者单纯接受常规西药治疗,观察组患者在对照组基础上接受健脾调肝法(应用以葛根、党参、茯苓、炒白术、当归、鸡内金等中药组成的健脾理气疏肝方)治疗,比较两组治疗有效率、空腹血糖(FBG)、餐后2h血糖(2h PBG)以及糖化血红蛋白(Hb A1c)、胃排空率、肠鸣音。结果观察组治疗有效率高于对照组,差异有统计学意义(P<0.05);治疗后,观察组患者FBG、2h PBG、Hb A1c水平低于对照组,差异有统计学意义(P<0.05);治疗后,观察组胃排空率、肠鸣音高于对照组,差异有统计学意义(P<0.05)。结论健脾调肝法治疗2型糖尿病胃肠功能紊乱疗效显著,应用价值较高。     

Central Bank's interventions and the Fisher hypothesis: a threshold cointegration investigation

The long-run relationship between nominal interest rates and inflation is examined, allowing for structural breaks and asymmetric mean reversion. From a Threshold AutoRegressive (TAR) test applied to the residuals of the cointegration relationship (while allowing for both a break in the mean of the long-run equation and a smooth regime-transition), there is strong evidence for non-linear mean reversion properties for the real interest rates of the US Treasury Bill market. This suggests asymmetric changes to inflation shocks in the Central Bank's reaction function. The existence of different regimes is consistent with some interpretations of the monetary policies run by the Fed, such as credibility and opportunism.