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51.
This study examined the parallel mediational processes between sensation seeking and parental rules on alcohol, in the emergence of heavy episodic drinking (HED) in adolescents. Data were drawn from a U.K. clustered randomized control trial (control arm only, N ≈ 6,300, Mage at baseline = 12.5). Using parallel process latent growth curve analysis, stricter parental rules at baseline were found to be associated with greater declines in sensation seeking over time and a lower risk of HED at follow‐up (+33 months). Higher initial levels of sensation seeking predicted a faster relaxation of parental rules and a greater risk of HED. By maintaining strict rules about alcohol, parents may promote a positive reduction in sensation seeking and a lower risk of HED.  相似文献   
52.
We examine how soda sales changed due to the campaign attention and election outcome of a local excise tax on sugar‐sweetened beverages. Using panel data of beverage sales from university retailers in Berkeley, California, we estimate that soda purchases relative to control beverages significantly dropped immediately after the election, months before the tax was implemented in the city of Berkeley or on campus. Supplemental scanner data from off‐campus retailers reveal this result is not unique to the university setting. Our findings suggest soda tax media coverage and election outcomes can have larger effects on purchasing behavior than the tax itself. (JEL D12, H20, C23, I38, Q18)  相似文献   
53.
Abstract

This article investigates the development and application of key performance indicators for global product development. Two in-depth, longitudinal case studies with multinational Danish manufacturing companies were conducted, and highlight how key performance indicators, typically used for collocated, cross-functional product development, do not provide the predictive insight required to avoid the additional risks encountered in the global product development environment. Grounded in the case study results and building on established methodologies in performance measurement literature, a framework was developed and validated in two additional Danish companies to support project managers to develop: preventive indicators, which support the avoidance of identified risks, and outcome indicators, which support the measurement towards the attainment of project objectives. The study is unique as it is one of the very few longitudinal studies of engineering design activities in a global context, providing the in-depth contextual understanding towards key risks and their influence on performance; an important step to support researchers and practitioners with the development of preventive measures.  相似文献   
54.
Conceptually, there is a common association between gambling games with fast speeds of play and problem gambling. This relationship however, is largely correlational in nature, which comes at the expense of carefully controlled empirical investigation. Research that does exist aimed towards investigating the impact of gambling speeds on psychological and behavioural factors, is in its relative infancy, and the research possesses disparate methodologies and variables of interest. The aims of the current review is therefore to evaluate and summarise the existing body of evidence relating to speed of play in gambling, as well as discuss how this evidence can be used to inform harm minimisation approaches aimed at facilitating self-control during gambling. Eleven studies were selected for review based on the inclusion criteria, comprising nine experimental and two qualitative studies (one self-report focus group study and one observational study). There was a consistent finding across studies that games with faster speeds of play were preferred and rated as more exciting for all gamblers, ranging from non-problem to problem gamblers. Of concern, was the repeated finding that fast games are particularly appealing to those suffering with a gambling problem. Behavioural results were more inconsistent across studies, though the general trend supports the notion that games with faster speeds of play encourage more wagers, longer game play, and caused players, particularly problem gamblers, to experience difficulty in ceasing gambling. The implications of these findings for gambling policy, harm minimisation approaches, and future research are discussed.  相似文献   
55.
56.
ABSTRACT

Despite both scholarly and popular claims that citizen journalism (CJ) represents a growing democratizing force in the journalistic field, recent scholarship in the area has noted the decline of the organizational population of CJ. In this paper, we investigate how individual characteristics of sites and the dynamics of larger organizational population affect a CJ site’s risk of experiencing a mortality. Drawing on the largest sample to date of US-based English-language CJ sites, this study examines the risk of site mortality through an event history framework. Findings indicate that the strongest predictor of a site’s mortality is the age of the site, consistent with organizational population theory’s ‘liability of newness.’ We also find that for-profit and community-based sites have lower rates of site mortality, indicating that adopting legitimate conventions of journalism may serve as a protective buffer to site death. The results offer mixed evidence on whether CJ has become more professionalized via attrition.  相似文献   
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58.
In the economic and social aftermath of the 2008 crisis there has been an important and growing new wave of highly qualified Portuguese emigration comprising scientists. No or very few public policies have been designed to reverse this phenomenon, risking the consequences of brain drain. International literature argues that professional reasons are central to scientists’ decision to migrate, even after the 2008 crisis. Spending some time in a foreign country to study, research, or teach, is perceived as a common step in an individual academic trajectory and an advantage for a successful professional career in academia. It is also encouraged by European Union policies. Twelve individual portraits of Portuguese scientists living in central Europe reveal how important other factors are to the migration decision‐making process. These factors include the economic crisis, student mobility programmes, and the current Portuguese scientific system revision.  相似文献   
59.
Association of demanding kin relations and family routine with adolescents' psychological distress and school achievement was assessed among 200 low‐income, African American mothers and adolescents. Demanding kin relations were significantly associated with adolescents' psychological distress. Family routine was significantly related to adolescents' school achievement. Demanding kin relations were negatively associated with school achievement for adolescents from families low in routine, but unrelated to achievement for adolescents in families high in routine. Additional research is needed on poor families and their social networks.  相似文献   
60.
The 2014 release of a new set of purchasing power parity (PPP) conversion factors (PPPs) for 2011 has prompted a revision of the World Bank’s international poverty line. In revising the line, we have sought to minimize changes to the real purchasing power of the earlier $1.25 line (in 2005 PPPs), so as to preserve the integrity of the goalposts for international targets such as the Sustainable Development Goals (SDGs) and the World Bank’s twin goals – which were set with respect to that line. In particular, the new line was obtained by inflating the same fifteen national poverty lines – originally used by Ravallion et al. (World Bank Econ. Rev. 23(2): 163–184 2009) to construct the $1.25 line – to 2011 prices in local currency units, and then converting them to US dollars using 2011 PPP conversion factors. With a small approximation, this procedure yields a new international poverty line of $1.90 per person per day. In combination with other changes described in the paper, this revision leads to relatively small changes in global poverty incidence for 2011: from 14.5 % using the old method to 14.1 % using the new method. In 2012, the new reference year for the global count, we find 12.7 % of the world’s population, or 897 million people, are living in extreme poverty. There are changes in the regional composition of poverty, but they are also relatively small. This paper documents methodological decisions taken in the process of updating both the poverty line and the consumption and income distributions at the country level, including issues of inter-temporal and spatial price adjustments. It also describes various caveats and limitations of the approach taken.  相似文献   
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