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721.
The purpose of this study was to assess the longitudinal association between adolescent dating relationship dynamics (measures of intimacy and problem dynamics), mental health, and physical and/or sexual victimization by a dating partner. Gender‐stratified analyses were conducted in a sample of 261 adolescents, ages 10–18 at baseline, interviewed in three annual waves (2013–2015) of the nationally representative Survey on Teen Relationships and Intimate Violence (STRiV). Among male daters, better mental health at baseline was negatively associated with problem dynamics at follow‐up, and aspects of problem dynamics at baseline predicted worse mental health at follow‐up. However, unexpectedly, aspects of relationship intimacy at baseline were also negatively associated with mental health at follow‐up. Male daters’ victimization did not mediate longitudinal measures of mental health or of relationship dynamics, but did predict worse mental health at follow‐up. Among female daters, we found no longitudinal associations between mental health and intimacy or problem relationship dynamics, in either direction. However, victimization mediated aspects of female daters’ reported relationship dynamics. Dating violence prevention efforts should reflect that adolescent females reporting controlling behaviors and feelings of passionate love may be at increased risk for victimization. Positive youth development efforts should attend to the bidirectional associations of mental health and dating relationship dynamics over time, particularly for male adolescents.  相似文献   
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There is an emerging need to advance linear mixed model technology to include variable selection methods that can simultaneously choose and estimate important effects from a potentially large number of covariates. However, the complex nature of variable selection has made it difficult for it to be incorporated into mixed models. In this paper we extend the well known class of penalties and show that they can be integrated succinctly into a linear mixed model setting. Under mild conditions, the estimator obtained from this mixed model penalised likelihood is shown to be consistent and asymptotically normally distributed. A simulation study reveals that the extended family of penalties achieves varying degrees of estimator shrinkage depending on the value of one of its parameters. The simulation study also shows there is a link between the number of false positives detected and the number of true coefficients when using the same penalty. This new mixed model variable selection (MMVS) technology was applied to a complex wheat quality data set to determine significant quantitative trait loci (QTL).  相似文献   
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This paper presents a new model incorporating features of developing country agriculture likely to shape the welfare outcomes of alternative agricultural policies. The model features heterogeneous households linked through markets in a rural economy-wide structure, with endogenous market participation for farmers facing transactions costs. We use it to simulate the impacts on rural welfare of market price supports, production subsidies, input subsidies, and the removal of transaction costs. Applications to six countries demonstrate the diversity of potential impacts, exhibit some systemic differences compared with impacts in developed countries, and identify specific circumstances under which market interventions may be only slightly less efficient than direct payments at transferring incomes to rural households.  相似文献   
727.
Two studies examined the factor structure of a modified version of the Safe Dates dating aggression scale and evaluated whether dating aggression is distinct from general aggression during early adolescence. Analyses were conducted on a derivation sample of 3,894 adolescents from 37 schools (Study 1) and an independent cross‐validation sample of 938 middle school youth (Study 2). Categorical confirmatory factor analyses supported a two‐factor model (perpetration and victimization) over models differentiating psychological and physical forms of aggression. The model was invariant across time, sex, grade, and season. Study 2 also supported dating aggression as distinct from general aggression. Results supported measuring dating aggression perpetration and victimization as latent constructs represented by ordered categorical indicators that capture item severity and frequency.  相似文献   
728.
This article considers the characteristics and utility of pro‐work policies targeting Australian older workers that have emerged in the context of population ageing, amid concerns that this will lead to labour shortages and an increasing social welfare burden. There has been a recent surge in public policy regarding the ageing workforce, the efficacy of which has not been tested by evaluation studies. After considering the conceptual foundations and objectives of various government initiatives, it is argued that the present public policy approach may have serious flaws that are not only detrimental to the stated overall objective of prolonging working lives, but may, in fact, be harmful to older workers and fail to address the needs of business. This stems from programs reaching only a small proportion of those older people who would potentially benefit from assistance, and from misdirected effort aimed at encouraging behavioural change on the part of employers or industries. It is argued that there is a need for greater targeting of policy efforts on the actual needs of industry and for public policy itself to become more age‐aware.  相似文献   
729.
Canada and the USA share a common cultural source in the British Empire, yet within shared democratic traditions, very different political structures, policy processes, and values have been identified. Canada is seen as having a more deferential culture more supportive of government while Americans have been argued to be more individualistic and cynical about the role of government in society. Using a political culture framework, this study examines the degree to which Canadian and U.S. civil servants perceive societal respect for their public sector jobs, and the impact of those perceptions on individual job satisfaction. It is argued that if civil servants feel more valued by society, they are more likely to have higher levels of public service motivation, which then contributes to higher levels of individual job satisfaction. This study employs surveys of Oregon, Washington and British Columbian civil servants conducted in 2011 and 2012 to investigate this relationship. Findings suggest that British Columbian civil servants feel more valued by society when compared to Oregon and Washington civil servants, and these perceptions of positive societal support are associated with higher levels of individual job satisfaction.  相似文献   
730.
Previous work has established that caregiver and child temperamental characteristics are associated with child compliance. Given the critical role that parents play in this process, and that children of teen mothers are at risk for poorer developmental outcomes, it is important to understand the development of compliance in the context of at‐risk parenting such as adolescent motherhood. The current study examined child compliance (Wave 5; W5) as a mediator of the association between adolescent mothers’ social competence (Wave 4; W4) and children's behavioral and academic outcomes (Wave 6; W6), and whether this mediation varied depending on children's effortful control (W4) in a sample of 204 Mexican‐origin adolescent mothers (Mage at W4 = 19.94, SD = .99) and their children (Mage at W4 = 36.21 months, SD = .45). Adolescent mothers reported on their own social competence and their children's effortful control and externalizing problems; compliance was assessed using observational methods; and academic readiness was assessed using standardized developmental assessments. Findings based on structural equation modeling revealed that adolescent mothers’ social competence was positively related to children's compliance among children with high effortful control, but not among those with low effortful control. Moreover, child compliance mediated the longitudinal association between adolescent mothers’ social competence and child externalizing problems and academic readiness. Discussion focuses on the importance of considering the role of child temperament in understanding how adolescent mothers’ social competence is subsequently associated with children's social and academic adjustment.  相似文献   
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