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91.
In a special paired sample case, Hotelling’s T2 test based on the differences of the paired random vectors is the likelihood ratio test for testing the hypothesis that the paired random vectors have the same mean; with respect to a special group of affine linear transformations it is the uniformly most powerful invariant test for the general alternative of a difference in mean. We present an elementary straightforward proof of this result. The likelihood ratio test for testing the hypothesis that the covariance structure is of the assumed special form is derived and discussed. Applications to real data are given.  相似文献   
92.
In the absence of reliable, internationally available migration flow data necessary for statistical forecasting, policymakers increasingly turn to survey data on emigration intentions to evaluate future migration trends. The important assumption – i.e. that there is a measurable and systematic relationship between the intention to migrate and actual migration – has not been firmly established at the international level. We examine the association between estimated population averages of emigration intentions and official migration flow data based on data for more than 160 countries. The results show a strong association between emigration intentions and recorded bilateral flows to industrialized countries, as well as between intentions and aggregated out‐migration. The results provide policymakers with a reliability assessment of survey data on emigration intentions and encourage future attempts to incorporate survey data in formal statistical migration forecasting models.  相似文献   
93.
We conduct an experiment that examines the relationship between girls only schooling and risk taking and competitive behavior. In it, we compare decisions made by students in an all‐girls' school to those made by students in a closely matched coeducational school. We further investigate the developmental nature of this behavior by comparing choices made by younger students (Grades 7 and 8) with those of older students (Grades 11 and 12). We focus on the differences between those who select into the all‐girls' school, and find that although girls educated in a single sex environment are the most risk averse, they are also among the most competitive. These results lend texture to the hypothesis that “nurture matters” in the gender differences debate. (JEL C93, J16, I21)  相似文献   
94.
The attempted Quality of Life Enhancement program appeared to be a novel method for creating a symbiotic and sustainable relationship between a large Southeastern university and local nursing home and assisted living facilities (ALF), through which ALF residents would attend university arts and sporting events. During implementation, it was discovered that this project was unsustainable, undesired, unneeded by many care centers, difficult to implement, and required a dedicated and specialized staff. After attempting to enroll 14 local care facilities, only 2 were interested in becoming involved and produced 5 eligible participants. During the program itself, coordination with facilities and residents was difficult to maintain and unique transportation and accommodation needs were challenging to overcome. Finally, data collection was time consuming and generally unfruitful. Ultimately the project was discontinued after a year of attempted recruitment and implementation of inclusive changes to protocol. While creating an ongoing relationship with local care facilities and local universities may enhance opportunities for residents and research into important areas, such relationships take time, effort, and specialized staff to maintain.  相似文献   
95.
Despite the possibility of burnout resulting from dynamics in firms' upper echelons, little if any work has focused on chief executive officer's (CEO's) burnout and firm performance. Drawing on managerial discretion theory, this article analyzes the influence of CEO burnout on firm performance and the moderating roles of the individual (CEO locus of control), structural power (CEO duality and CEO tenure), and organizational characteristics (size, age, and resource availability) related to managerial discretion. Using a sample of 156 CEOs in Swedish firms, we find a negative association between CEOs who report higher burnout and firm performance. Our results confirm that CEO duality and resource availability ameliorate and firm size exacerbates the negative association between CEO burnout and firm performance. Contrary to our expectations, CEO locus of control, CEO tenure, and firm age do not influence this relationship. We discuss the implications of our research for upper echelons theory and strategic leadership theory.  相似文献   
96.
ABSTRACT

We describe two recently proposed machine learning approaches for discovering emerging trends in fatal accidental drug overdoses. The Gaussian Process Subset Scan (Herlands, McFowland, Wilson, & Neill, 2017 Neill, D. B. (2017). Multidimensional tensor scan for drug overdose surveillance. Journal of Public Health Informatics, 9(1), e20. doi:10.5210/ojphi.v9i1.7598[Crossref] [Google Scholar]) enables early detection of emerging patterns in spatio-temporal data, accounting for both the complex, correlated nature of the data and the fact that detecting subtle patterns requires integration of information across multiple spatial areas and multiple time steps. We apply this approach to 17 years of county-aggregated data for monthly opioid overdose deaths in the New York City metropolitan area, showing clear advantages in the utility of discovered patterns as compared to typical anomaly detection approaches. To detect and characterize emerging overdose patterns that differentially affect a subpopulation of the data, including geographic, demographic, and behavioral patterns (e.g., which combinations of drugs are involved), we apply the Multidimensional Tensor Scan (Neill, 2017 Neill, D. B. (2017). Multidimensional tensor scan for drug overdose surveillance. Journal of Public Health Informatics, 9(1), e20. doi:10.5210/ojphi.v9i1.7598[Crossref] [Google Scholar]) to 8 years of case-level overdose data from Allegheny County, Pennsylvania. We discover previously unidentified overdose patterns which reveal unusual demographic clusters, show impacts of drug legislation, and demonstrate potential for early detection and targeted intervention. These approaches to early detection of overdose patterns can inform prevention and response efforts, as well as understanding the effects of policy changes.  相似文献   
97.

Background

Previous physical activity (PA) tracking studies have examined the stability of overall PA and/or PA types, but few have investigated how specific types of sport/exercise track over the life course. The aim of this study was to determine how specific sports/exercises in midlife track and predict future sport/exercise and PA in men transitioning to old age.

Methods

Seven thousand seven hundred thirty-five men (aged 40–59?years) recruited in 1978–80 were followed up after 12, 16 and 20?years. At each wave men self-reported participation in sport/exercise. Frequent sport/exercise participants (>?1/month) reported the types of sport/exercise they engaged in. Men also reported total PA, health status, lifestyle behaviours and socio-demographic characteristics. Stability of each sport/exercise was assessed using kappa statistics and intraclass correlation coefficients. Logistic regression estimated the odds of participating in sport/exercise and being active at 20-year follow up according to specific types of sport/exercise in midlife.

Results

Three thousand three hundred eighty-four men with complete data at all waves were included in analyses. Tracking of specific sports/exercises ranged from fair to substantial, with golf being the most common and most stable. Bowls was the most frequently adopted. Odds of participating in sport/exercise and being active in old age varied according to sport/exercise types in midlife. Golf and bowls in midlife were the strongest predictors of sport/exercise participation in old age. Golf, cricket and running/jogging in midlife were among the strongest predictors of being active in old age. Compared to participating in just one sport/exercise in midlife, sampling multiple sports/exercises was more strongly associated with sport/exercise participation and being active in old age.

Conclusion

The stability of sport/exercise participation from midlife to old age varies by type. Specific sports/exercises in midlife may be more likely to predict future PA than others. However, participating in a range of sports/exercises may be optimal for preserving PA into old age.
  相似文献   
98.
Despite recent increases of psychosocial programs for pediatric chronic illness, few studies have explored their economic benefits. This study investigated the costs–benefits of a family systems‐based, psychosocial intervention for pediatric chronic illness (MEND: Mastering Each New Direction). A quasi‐prospective study compared the 12‐month pre–post direct and indirect costs of 20 families. The total cost for program was estimated to $5,320. Families incurred $15,249 less in direct and $15,627 less in indirect costs after MEND. On average, medical expenses reduced by 86% in direct and indirect costs, for a cost–benefit ratio of 0.17. Therefore, for every dollar spent on the program, families and their third payers saved approximately $5.74. Implications for healthcare policy and reimbursements are discussed.  相似文献   
99.
This study examined vocational identity as a mediator of the relationship between occupational engagement (i.e., participation in a breadth of activities and interactions) and academic major satisfaction. Furthermore, the authors evaluated whether satisfaction with academic major related to academic success (i.e., grade point average). The mediational model was tested in a sample of undergraduate students (N = 215). Results indicated that occupational engagement significantly predicted academic major satisfaction and that vocational identity fully mediated that relationship. These findings support occupational engagement as an important contributor to adaptive career decision making and encourage research on occupational engagement as an intervention point for career counselors.  相似文献   
100.
Johan A. Oldekop  Lorenza B. Fontana  Jean Grugel  Nicole Roughton  Emmanuel A. Adu‐Ampong  Gemma K. Bird  Alex Dorgan  Marcia A. Vera Espinoza  Sara Wallin  Daniel Hammett  Esther Agbarakwe  Arun Agrawal  Nurgul Asylbekova  Clarissa Azkoul  Craig Bardsley  Anthony J. Bebbington  Savio Carvalho  Deepta Chopra  Stamatios Christopoulos  Emma Crewe  Marie‐Claude Dop  Joern Fischer  Daan Gerretsen  Jonathan Glennie  William Gois  Mtinkheni Gondwe  Lizz A. Harrison  Katja Hujo  Mark Keen  Roberto Laserna  Luca Miggiano  Sarah Mistry  Rosemary J. Morgan  Linda L. Raftree  Duncan Rhind  Thiago Rodrigues  Sonia Roschnik  Flavia Senkubuge  Ian Thornton  Simon Trace  Teresa Ore  Ren Mauricio Valds  Bhaskar Vira  Nicola Yeates  William J. Sutherland 《Development policy review : the journal of the Overseas Development Institute》2016,34(1):55-82
The Sustainable Development Goals (SDGs) herald a new phase for international development. This article presents the results of a consultative exercise to collaboratively identify 100 research questions of critical importance for the post‐2015 international development agenda. The final shortlist is grouped into nine thematic areas and was selected by 21 representatives of international and non‐governmental organisations and consultancies, and 14 academics with diverse disciplinary expertise from an initial pool of 704 questions submitted by 110 organisations based in 34 countries. The shortlist includes questions addressing long‐standing problems, new challenges and broader issues related to development policies, practices and institutions. Collectively, these questions are relevant for future development‐related research priorities of governmental and non‐governmental organisations worldwide and could act as focal points for transdisciplinary research collaborations.  相似文献   
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