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In this paper, we study a nonparametric additive regression model suitable for a wide range of time series applications. Our model includes a periodic component, a deterministic time trend, various component functions of stochastic explanatory variables, and an AR(p) error process that accounts for serial correlation in the regression error. We propose an estimation procedure for the nonparametric component functions and the parameters of the error process based on smooth backfitting and quasimaximum likelihood methods. Our theory establishes convergence rates and the asymptotic normality of our estimators. Moreover, we are able to derive an oracle‐type result for the estimators of the AR parameters: Under fairly mild conditions, the limiting distribution of our parameter estimators is the same as when the nonparametric component functions are known. Finally, we illustrate our estimation procedure by applying it to a sample of climate and ozone data collected on the Antarctic Peninsula. 相似文献
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Robert C. Cope Joshua V. Ross Talia A. Wittmann Michael J. Watts Phillip Cassey 《Risk analysis》2019,39(1):35-53
Understanding the risk of biological invasions associated with particular transport pathways and source regions is critical for implementing effective biosecurity management. This may require both a model for physical connectedness between regions, and a measure of environmental similarity, so as to quantify the potential for a species to be transported from a given region and to survive at a destination region. We present an analysis of integrated biosecurity risk into Australia, based on flights and shipping data from each global geopolitical region, and an adaptation of the “range bagging” method to determine environmental matching between regions. Here, we describe global patterns of environmental matching and highlight those regions with many physical connections. We classify patterns of global invasion risk (high to low) into Australian states and territories. We validate our analysis by comparison with global presence data for 844 phytophagous insect pest species, and produce a list of high‐risk species not previously known to be present in Australia. We determined that, of the insect pest species used for validation, the species most likely to be present in Australia were those also present in geopolitical regions with high transport connectivity to Australia, and those regions that were geographically close, and had similar environments. 相似文献
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Urban Ecosystems - Critical resources for birds nesting in cities can support populations in spite of the challenges imposed by urbanization, and the identification of such resources can shed light... 相似文献
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Urban Ecosystems - Residential yardscapes are at the forefront of human interaction with nature for those living in urban areas across Europe and North America. In recent years a significant amount... 相似文献
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David L. Albright Lauren Holmes Michael Lawson Justin McDaniel Kirsten Laha-Walsh Shanna McIntosh 《Journal of social work practice in the addictions》2020,20(1):46-58
ABSTRACTAlcohol and substance use can challenge military veterans who live in rural communities. In 2016, the screening, brief intervention, and referral to treatment in Alabama (AL-SBIRT) program was implemented in west Alabama. The primary aim of this study was to determine whether current tobacco use modified the relationship between veteran status and substance misuse. Self-reported wellness data was collected regarding substance, alcohol, or tobacco consumption. Risk levels for alcohol and drug use were measured using the United States Alcohol Use Disorders Identification Test (US-AUDIT) and the Drug Abuse Screening Test (DAST)-10. Substance and tobacco use were significantly and positively correlated. Veterans had a higher US-AUDIT and DAST score than nonveterans, and tobacco appeared to be an exacerbating factor. Effective evidence-based interventions are needed in rural settings. Technology based programs and motivational interviewing with trained clinicians may serve as beneficial and cost-effective interventions for tobacco use prevention and cessation efforts. 相似文献
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AbstractThis article discusses how the history of sports can serve as way to understand abstract concepts associated with local history and social studies education. An introductory discussion outlines how sports can engage and interest students, focusing especially on ideas related to history thinking (such as change and continuity). A case study using the Brooklyn Dodgers’ move to Los Angeles is used to illustrate these ideas, focusing on themes associated with suburbanization and urban renewal. A lesson plan is also provided. 相似文献
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AbstractNudge theory describes how indirect suggestions and positive reinforcement can influence decision-making. We used nudge theory to implement a traffic-light labeling and choice architecture (modifying product placement) intervention at Harvard University cafeterias, but found no significant change in sales. Survey and focus group data showed that some students thought the labeling may exacerbate eating disorders, however, there is extremely limited research on potential negative consequences of labeling. One way to describe these findings is through 20th century philosopher Michel Foucault’s concept of biopower. Biopower manipulates cultural norms and nudges individuals to engage in self-surveillance and self-discipline, de facto subjugating themselves to certain ways of being. Biopower may lead to the creation of an in-group and an out-group based on who can adopt the new behaviors, such as healthy eating. Those in the out-group may face additional unintended consequences, highlighting the need for mixed-methods research to better evaluate public health interventions. 相似文献