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1.
We provide evidence on the existence of short-run trade diversion effects towards third countries as a consequence of tariff shocks. We exploit sudden policy changes in the context of the trade dispute between the United States and China in 2018. Based on a data set covering monthly product-level information on US imports from 30 countries for the period 2016 until May 2019, we employ a difference-in-differences estimation framework. Doing so, we can show a strong negative direct effect of US tariffs on US imports from China, but do not find evidence for significant short-run trade diversion effects towards third countries.  相似文献   
2.
当前,我国农村生态治理已取得长效发展,但也面临着共同体理念淡漠、信任性组织松散、对称性信息堵塞、技术性监管悖论等问题与挑战。农村生态治理数据人才主体缺失、数据监管体系薄弱、政务数据信息传递遗漏、生态技术伦理道德欠缺是造成农村生态治理式微的深层次原因,因此,必须将大数据技术嵌入农村生态治理,提高农村生态治理效能。革新数据治理的顶层设计,完善数据治理的网络机制,重塑数据治理的信息平台,完善数据治理的监管体系,建立生态治理数据决策模式,以实现大数据时代农村生态治理的现代化转型。  相似文献   
3.
Funding decisions to support vulnerable children are tied to child labour statistics, hence the importance of an accurate measurement. The author analyses whether the type of respondent plays an important role in explaining variations in child labour statistics. Using data from two sites in Tanzania, the analysis shows that “whom we ask” matters considerably when estimating the prevalence of child labour. The results suggest that prevalence increases by approximately 35 to 65 per cent when using child self‐reports rather than proxy reports. This bias affects 14 to 31 per cent of the sample, depending on the indicator. Discrepancies decrease as the child ages and increase if proxy attitudes demonstrate opposition to child labour.  相似文献   
4.
ABSTRACT

Social network services are allowing more social connectivity and making possible sharing information and knowledge of a different nature. This article analyses if social workers related to active social policies from Malaga province (Spain) are using social network services to share information and knowledge and if there is a mirror between online and offline relationships. Since it is an experimental model, through virtual ethnography and through social network analysis methodology, we observed the presence, connectivity and analysed the structure of relationships that keep 235 professionals from 52 organizations in Facebook®. Moreover, the model uses the statistical technique of modularity for detecting online communities, which are compared with distribution of professionals in their organizations. Results show how social network services applied to social intervention are massively and frequently used by professionals. On the other hand, the detected communities reflect existence of analogy between online and offline relationships. The online structure shows a high degree of cohesion and how certain professionals have higher capacity of influence and diffusion depending on position in the online structure. It argues about the opportunity to incorporate social network services towards social intervention as a manner of social innovation to improve cooperation and diffusion of information and knowledge.  相似文献   
5.
大数据战略视野下我国信息网络安全立法分析   总被引:3,自引:1,他引:2  
大数据战略视野下,很多国家纷纷制定、完善和执行着自己的信息网络安全法律,并已形成世界潮流.从国内外的大数据战略与信息网络安全立法分析来看,我国既有成绩,也有不足.对于我国信息网络安全的法律保障,目前需要完善的主要内容有:进一步明确国家信息网络安全立法的目的与宗旨;基本法层面,尽快构建完备的信息网络安全法律保障有机体系,重点包括政府信息公开法与个人信息保护法等;实施层面,加强与完善具体领域的单行法与配套法建设,增强法律规定的可操作性;完善法律框架之外的协作保障体系.  相似文献   
6.
针对随机波动条件持续期模型(SCD模型)对于金融超高频数据的模拟优势,采用股票交易的分笔数据,在模型中引入消息指标变量、交易量和买卖价差三类微观结构变量,通过分析价格持续期与这些结构变量之间的相关性,以研究价格形成过程中的信息传递过程。研究结果表明:利好消息通常导致交易强度增加,利空消息通常会导致交易持续期延长,价格变化对交易持续期造成的影响有限;小盘股买卖价差影响后续价格交易持续期,但大盘股的影响并不明显;交易量的增加具有信息含量。  相似文献   
7.
ABSTRACT

Scientific research of all kinds should be guided by statistical thinking: in the design and conduct of the study, in the disciplined exploration and enlightened display of the data, and to avoid statistical pitfalls in the interpretation of the results. However, formal, probability-based statistical inference should play no role in most scientific research, which is inherently exploratory, requiring flexible methods of analysis that inherently risk overfitting. The nature of exploratory work is that data are used to help guide model choice, and under these circumstances, uncertainty cannot be precisely quantified, because of the inevitable model selection bias that results. To be valid, statistical inference should be restricted to situations where the study design and analysis plan are specified prior to data collection. Exploratory data analysis provides the flexibility needed for most other situations, including statistical methods that are regularized, robust, or nonparametric. Of course, no individual statistical analysis should be considered sufficient to establish scientific validity: research requires many sets of data along many lines of evidence, with a watchfulness for systematic error. Replicating and predicting findings in new data and new settings is a stronger way of validating claims than blessing results from an isolated study with statistical inferences.  相似文献   
8.
This paper discusses regression analysis of clustered current status data under semiparametric additive hazards models. In particular, we consider the situation when cluster sizes can be informative about correlated failure times from the same cluster. To address the problem, we present estimating equation-based estimation procedures and establish asymptotic properties of the resulting estimates. Finite sample performance of the proposed method is assessed through an extensive simulation study, which indicates the procedure works well. The method is applied to a motivating data set from a lung tumorigenicity study.  相似文献   
9.
We propose novel parametric concentric multi‐unimodal small‐subsphere families of densities for p ? 1 ≥ 2‐dimensional spherical data. Their parameters describe a common axis for K small hypersubspheres, an array of K directional modes, one mode for each subsphere, and K pairs of concentrations parameters, each pair governing horizontal (within the subsphere) and vertical (orthogonal to the subsphere) concentrations. We introduce two kinds of distributions. In its one‐subsphere version, the first kind coincides with a special case of the Fisher–Bingham distribution, and the second kind is a novel adaption that models independent horizontal and vertical variations. In its multisubsphere version, the second kind allows for a correlation of horizontal variation over different subspheres. In medical imaging, the situation of p ? 1 = 2 occurs precisely in modeling the variation of a skeletally represented organ shape due to rotation, twisting, and bending. For both kinds, we provide new computationally feasible algorithms for simulation and estimation and propose several tests. To the best knowledge of the authors, our proposed models are the first to treat the variation of directional data along several concentric small hypersubspheres, concentrated near modes on each subsphere, let alone horizontal dependence. Using several simulations, we show that our methods are more powerful than a recent nonparametric method and ad hoc methods. Using data from medical imaging, we demonstrate the advantage of our method and infer on the dominating axis of rotation of the human knee joint at different walking phases.  相似文献   
10.
The aim of this study was to explore how particular economic and demographic factors contribute to the level of the child maintenance payment (CMP) paid by the non‐resident parent. For this study, we used 5‐year longitudinal panel data from years 2009 to 2013 consisting of over 80,000 non‐resident parents from the Finnish Tax Administration and The Finnish Population Register Centre. Results from regression models indicate that the single biggest factor affecting the size of CMPs is the number of dependent children. We found that the non‐resident parent's higher income is associated with higher CMPs and that non‐resident fathers pay on average larger CMPs than non‐resident mothers, even after accounting for differences in income. Unexpectedly, we found that the age of the dependent child did not predict changes in CMPs. This suggests that once formal CMP‐contracts are determined between the parents, they are seldom changed. Our results suggest that some degree of mandatory periodic review for maintenance contracts is worth considering.  相似文献   
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