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1.
目前有许多研究将两阶段DEA模型应用到科技创新活动当中,一般将创新活动分为研发和转化两个阶段,为了进一步探讨不同转移转化方式下科技成果的转化效率以获得更多的详细信息,本文拓展了传统的两阶段DEA模型,考虑了嵌套并联结构的两阶段网络DEA模型,将科技创新活动分为科技成果研发阶段和科技成果转化阶段,并将科技成果转化阶段分为内部转化和外部转化两个并联子系统。本文选取14家中科院院属单位作为被评价对象,应用加权加法分解方法计算整体效率和各阶段子效率。通过将本文模型与传统两阶段模型进行对比发现,传统模型会低估科技成果转化效率。结果表明:整体科技创新效率均值偏低,科技成果研发效率均值高于科技成果转化效率均值,科技成果转化效率仍有很大的提升空间。科技成果转化阶段中内部转化效率普遍较高但是外部转化效率普遍较低,较低的外部转化效率是导致科技成果转化效率低下的主要原因。最后,本文将所有被评价单位分为四类机构,分析提高科技创新效率的实现路径,可以通过重点突破模式和渐进突破模式来实现整体效率的提高。 相似文献
2.
Linking taxation and social protection: Evidence on redistribution and poverty reduction in Ethiopia 下载免费PDF全文
Although redistribution results from the simultaneous effects of taxes and transfers, analyses of their distributional effects in low‐income countries have largely been undertaken from singular perspectives. This article jointly assesses the distributional effect of taxes and transfers (through social protection) using Ethiopia as a case study. We find that Ethiopia's flagship social protection programme is more effective than income taxation in achieving poverty reduction, while neither policy achieves a sizeable reduction in overall inequality. We also find that Ethiopia does not currently have the capacity to close the poverty gap or to fully fund its main safety net programme using domestic income sources alone. 相似文献
3.
聂清华 《长春工程学院学报(社会科学版)》2015,(2):67-70
鉴于信用证具有比较强的收汇保障的性能和贸易融资功能,因此也一直是我国出口企业贸易结算的首选,使用率高居90%。但是近年来,其结算的“霸主”地位不断弱化,并由此对我国外贸出口产生了较大的不利影响。本文探讨了其中具体的原因及影响,并辅以对策。 相似文献
4.
Simulation results are reported on methods that allow both within group and between group heteroscedasticity when testing the hypothesis that independent groups have identical regression parameters. The methods are based on a combination of extant techniques, but their finite-sample properties have not been studied. Included are results on the impact of removing all leverage points or just bad leverage points. The method used to identify leverage points can be important and can improve control over the Type I error probability. Results are illustrated using data from the Well Elderly II study. 相似文献
5.
四川盆地卤水分布广泛,资源丰富, 早为世人所瞩目,中三叠统雷口坡组是四川盆地最早开采天然气和盐卤的层系之一。根据盆地雷口坡组大量钻井资料研究表明,盆地雷口坡组主要成盐期分别为雷三2 期和雷四2 期,在盆地东部和南部由于受到古隆起的影响,盐岩地层已被剥蚀难以保存,现今盐岩主要分布在开江古隆起和泸州古隆起的西部以及天井山古隆起的南部(华蓥山以西—龙门山以东的川西—川中地区)。印支运动对盆地雷口坡组盐岩在平面的迁移起着十分重要的作用,根据不同时期盐岩统计数据看,两期盐盆在平面上具有向西迁移、叠加的特征,其中川中的GS1 井就钻遇了这两期的盐岩。 相似文献
6.
In some situations, for example in agriculture, biology, hydrology, and psychology, researchers wish to determine whether the relationship between response variable and predictor variables differs in two populations. In other words, we are interested in comparing two regression models for two independent datasets. In this work, we will use the parametric and nonparametric methods to establish hypothesis testing for the equality of two independent regression models. Then the simulation study is provided to investigate the performance of the proposed method. 相似文献
7.
Jennifer M. Cadigan Emily R. Dworkin Jason J. Ramirez Christine M. Lee 《Journal of American college health : J of ACH》2019,67(4):383-390
Objective: The objective of this study was to understand substance use patterns of alcohol, marijuana, and simultaneous alcohol and marijuana (SAM) use among 2- and 4-year college students. Participants: Participants were 526 young adults aged 18–23 (n?=?355 4-year students; n?=?171 2-year students) recruited from February 2015 to January 2016 who were participating in a larger longitudinal study. Methods: Latent class analysis (LCA) was used to identify past-month classes of alcohol, marijuana, and SAM use. Results: Among both 2- and 4-year students, a four-class solution yielded the best-fitting model, with 2-year classes tending to include greater marijuana use and less alcohol use and 4-year classes tending to include heavy alcohol use. Demographic characteristics were largely similar across classes. Conclusions: Classes of alcohol, marijuana, and SAM use differed by education status. Screening and prevention efforts for 4-year students may need to be tailored for the needs of 2-year students. 相似文献
8.
本研究以68名幼儿为研究对象,运用《游戏检核表》对其社会戏剧游戏水平进行调查,研究发现:4-6岁幼儿角色扮演、口语交流、互动和同伴支持水平高,游戏时间充分;但物品假装、如何进入游戏小组、问题解决和轮流技能较低。教师应通过明确自身角色、丰富幼儿游戏材料和经验、提升幼儿语言能力和社会交往技能促进幼儿社会戏剧游戏发展。 相似文献
9.
This article analyzes a growing group of fixed T dynamic panel data estimators with a multifactor error structure. We use a unified notational approach to describe these estimators and discuss their properties in terms of deviations from an underlying set of basic assumptions. Furthermore, we consider the extendability of these estimators to practical situations that may frequently arise, such as their ability to accommodate unbalanced panels and common observed factors. Using a large-scale simulation exercise, we consider scenarios that remain largely unexplored in the literature, albeit being of great empirical relevance. In particular, we examine (i) the effect of the presence of weakly exogenous covariates, (ii) the effect of changing the magnitude of the correlation between the factor loadings of the dependent variable and those of the covariates, (iii) the impact of the number of moment conditions on bias and size for GMM estimators, and finally (iv) the effect of sample size. We apply each of these estimators to a crime application using a panel data set of local government authorities in New South Wales, Australia; we find that the results bear substantially different policy implications relative to those potentially derived from standard dynamic panel GMM estimators. Thus, our study may serve as a useful guide to practitioners who wish to allow for multiplicative sources of unobserved heterogeneity in their model. 相似文献
10.
Post-crisis policy making increasingly focuses on doing business reforms. We argue that the effects of those reforms will be different across countries. To understand the reasons for the reform outcome divergence, we advance a novel firm-size distribution (FSDs) argument. At the center of the argument is the fact that FSDs are different across countries and stable over time. Then, if a given doing business reform induces firms of different size to grow differently, this will produce a variety of reform outcomes across countries. To advance the argument, we set up a tractable general equilibrium (GE) model and study how firms of different size grow after a doing business reform. The model predicts that larger firms will grow faster than smaller firms after the reform. The model predictions are tested on the Enterprise Surveys (ES) data, merged with the Doing Business indicators. We confirm that firms of different size grow differently after a Doing Business reform. Thus, based on the notable differences of firm size distributions across countries, identical reforms to start, operate and close a business will produce a variety of reform outcomes across countries. 相似文献