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61.
Crowdfunding platforms serve to connect project creators and backers. Previous research has explored several project and platform determinants that impact crowdfunding outcomes. However, there has been limited research on these determinants at an individual level. Our paper addresses how backers may influence the outcomes of projects in crowdfunding platforms. We explore several methods commonly used in the industry to identify influence and show that centrality measures through a backer affiliation network best exemplifies influence. Using data from Kickstarter, we construct a weighted backer network based on 52,678 common projects backed by 11,134 backers. Controlling for digital media mentions and project quality, we find evidence that backers in central positions within the network have a positive impact on multiple project outcomes such as the project success rates, amount of funds raised, speed of reaching the crowdfunding goal as well as the number of backers contributing to the project. These findings are replicated and reinforced by using data from a different crowdfunding platform using the entire backer network based on 1095 projects backed by 87,896 backers. Several robustness tests are used to validate these results.  相似文献   
62.
This paper examines local influence assessment in generalized autoregressive conditional heteroscesdasticity models with Gaussian and Student-t errors, where influence is examined via the likelihood displacement. The analysis of local influence is discussed under three perturbation schemes: data perturbation, innovative model perturbation and additive model perturbation. For each case, expressions for slope and curvature diagnostics are derived. Monte Carlo experiments are presented to determine the threshold values for locating influential observations. The empirical study of daily returns of the New York Stock Exchange composite index shows that local influence analysis is a useful technique for detecting influential observations; most of the observations detected as influential are associated with historical shocks in the market. Finally, based on this empirical study and the analysis of simulated data, some advice is given on how to use the discussed methodology.  相似文献   
63.
The scientific literature stresses the importance of culture and social environment in determining what people think about alcohol consumption and consequently do. Several pieces of research have proved the influence on young adults’ alcohol use of proximal social contexts of their family and peers. The present study aimed at investigating the influence of family behaviours and norms compared to the peers’ influence in a context where the culture of alcohol is changing between the different generations. Data were collected by means of a self-report questionnaire on a sample of 598 young adults (average age 22.20 years). The variables investigated were socio-demographic characteristics, the alcohol consumption of parents and friends and the parents’ and peers’ approval of alcohol consumption. The results confirmed the role of family and friends in influencing young adults’ consumption of alcohol, stressing a difference between perceived behaviours and norms. The perceived consumption of parents and friends influenced the participants’ consumption. On the contrary, the effects of the approval of drinking were limited. Globally friends had a stronger influence on alcohol consumption in comparison with family.  相似文献   
64.
近年来,发达国家电子废弃物的流入给发展中国家的环境和民众健康带来了严重的危害。我国在阻止电子废弃物流入的相关法律规制与监管上存在漏洞,且经济发展战略不合理,发展水平相对落后。法律和经济方面的双重落差导致发达国家电子废弃物流入屡禁不止,迫切需要采取有效措施加以应对。分析国外电子废弃物涌入我国之现状与原因,并从法律制度建设、经济发展思路、经济发展战略、国内管理和国际合作5方面提出应对策略。  相似文献   
65.
Evaluation capacity building (ECB) is a context-dependent process. Contextual factors affecting ECB implementation have been explored theoretically and practically, but their influence within a changing environment has seldom been discussed. This study examined essential context-sensitive parameters, particularly those involved in implementing new governmental policies regarding higher education. Taiwan was used as a case study for exploring the effect of contextual change on ECB attributes from the perspectives of training receivers and providers. Surveys and interviews were used for data collection and importance–performance analysis was applied for data analysis. Four prominent features were identified. First, the ECB attributes perceived as important by receivers were performed adequately, whereas those perceived as less important were performed less well. Second, under new policies, training provider designed training covering a wide range of ECB, whereas receivers focused on those can be directly applied in evaluation process. Third, in a small education system such as Taiwan’s, the complexity of peer review is high and ethical issues become important. Fourth, because the evaluation structure has been changed from single- to dual-track, receivers expect more training for institution staff, whereas providers insist on hierarchical training. Aligning ECB supply and needs is paramount for adaptation to new policies.  相似文献   
66.
人的思想道德是人口素质的重要内容,人的思想道德在经济增长和经济发展中具有重要作用。但目前学术界还缺乏对人的思想道德素质与经济增长、经济发展和脱贫致富相关性的理论分析与实证检验。新时期反贫困实践应重视思想反贫困和思想扶贫。  相似文献   
67.
Youth’s perceptions of peer norms have profound effects on their attitudes and behaviors. Unfortunately, their perceptions of peers tend to be biased. To investigate the role of media in the formation of misperceived peer norms, the current study tested and compared two media-effect mechanisms: the direct exemplar mechanism and the indirect influence of presumed influence (IPI) mechanism. The two mechanisms were tested in a sample (n = 1746) that is representative of college students in one large university in China, based on which the actual and perceived campus smoking rates were examined. The individual-level perceived peer smoking prevalence was then analyzed in comparison with the campus-level actual smoking prevalence. The results revealed serious overestimations of peer smoking prevalence. As predicted, pro-smoking media content significantly heightened smoking prevalence estimates through both exemplar and IPI mechanisms. In contrast, anti-smoking messages did not elicit any intended effect through the IPI mechanism, but showed a boomerang effect through the exemplar mechanism. These findings suggest that both pro- and anti-smoking media content may be responsible for inflated perceptions of peer smoking among youth.  相似文献   
68.
How peer groups contribute to educational outcomes has long interested researchers. However, the possibility that peer groups dominated by either low- or high-achieving youth can have substantively different effects on achievement has been largely ignored. In this paper, we show that while being embedded in a high-achieving network of friends is not associated with increased own achievement, being embedded in a low-achieving network is associated with decreased own achievement. In additional analyses, we present evidence that these associations are at least in part due to influence, as opposed to only selection effects or shared environment. We also examine whether the structure of the network in which a student is embedded might affect their educational achievement. We show that achieving at higher levels positively predicts how centrally located a student is in their network, but being more centrally located does not predict concurrent achievement. This finding suggests that the behavior of individuals is affecting the formation of network structure and not the reverse.  相似文献   
69.
采用全国老年人口健康状况调查项目2002年~2005年纵向数据作为研究样本,对中国老年人社会健康的影响因素进行多维分析。通过结构方程模型,在方法上解决了社会健康的多维性、抽象概念的定量分析和测量误差的问题。研究发现,经济社会因素是影响老年人社会健康的主要方面,其中老年人自身的经济条件是最重要的因素;心理健康是影响老年人社会健康的关键因素,其它因素通过心理健康对社会健康起间接作用;由于社会生活方式的改变,家庭因素对老年人社会健康的直接影响正在弱化,但是家庭因素对老年人社会健康的间接影响依然存在。  相似文献   
70.
We describe methods to detect influential observations in a sample of pre-shapes when the underlying distribution is assumed to be complex Bingham. One of these methods is based on Cook's distance, which is derived from the likelihood of the complex Bingham distribution. Other method is related to the tangent space, which is based on the local influence for the multivariate normal distribution. A method to detect outliers is also explained. The application of the methods is illustrated in both a real dataset and a simulated sample.  相似文献   
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