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141.
142.
In response surface methodology, one is usually interested in estimating the optimal conditions based on a small number of experimental runs which are designed to optimally sample the experimental space. Typically, regression models are constructed from the experimental data and interrogated in order to provide a point estimate of the independent variable settings predicted to optimize the response. Unfortunately, these point estimates are rarely accompanied with uncertainty intervals. Though classical frequentist confidence intervals can be constructed for unconstrained quadratic models, higher order, constrained or nonlinear models are often encountered in practice. Existing techniques for constructing uncertainty estimates in such situations have not been implemented widely, due in part to the need to set adjustable parameters or because of limited or difficult applicability to constrained or nonlinear problems. To address these limitations a Bayesian method of determining credible intervals for response surface optima was developed. The approach shows good coverage probabilities on two test problems, is straightforward to implement and is readily applicable to the kind of constrained and/or nonlinear problems that frequently appear in practice. 相似文献
143.
Richard Eckersley 《Social indicators research》2009,94(1):1-12
This article focuses on the contributions and, importantly, the limitations of subjective wellbeing (happiness/satisfaction)
measures as indicators of broad population wellbeing and societal functioning. The popular practice of comparing happiness
among countries gives a skewed view of how well their people are faring. Charting trends over time in happiness and mental
health gives contradictory pictures of population wellbeing; even the responses to different questions within the same survey
can yield very different findings. Asking people about their own lives and about social conditions produces contrasting results.
These issues challenge the orthodox model of human development, which places Western liberal democracies at its leading edge.
According to an alternative, psychosocial-dynamics, model, some, at least, may be societies in decline. Reconciling these
views is no simple matter. 相似文献
144.
Robert D. Crutchfield Martie L. Skinner Kevin P. Haggerty Anne McGlynn Richard F. Catalano 《Race and social problems》2009,1(4):218-230
Criminologists have long reported the existence of racial disparity in the criminal justice system, but the important question
is why. While some argue that observed differences are a consequence of more criminal behavior among minorities, the weight
of the evidence indicates that this is but a partial explanation. In this paper, we study data from a sample of juveniles
to examine how racial differences in early police contact, and important social environments—family, school, and neighborhoods—affect
later contact and arrests, controlling for self-reported delinquency. We find that early (in middle school) contact with police
is an important predictor of later (high school) arrests. Also we found that, in addition to being male and living in a low-income
family, children who have parents who have a history of arrest, who have experienced school disciplinary actions, who have
delinquent peers, and who are in networks with deviant adults are more likely to have problems with law enforcement. These
factors help to explain racial differences in police contacts and arrests. 相似文献
145.
Margarita Frederico Associate Professor Maureen Long Patricia McNamara Lynne McPherson Richard Rose Associate Professor 《Child & Family Social Work》2017,22(2):1064-1074
How best to support children and young people in foster care remains a challenge for child welfare. There has been little Australian research on the outcomes for children and young people placed in therapeutic foster care (TFC). This article aims to address this knowledge gap, presenting the evaluation of a state‐wide model of TFC known as the Circle Program operating in Victoria, Australia. Data sources for the study were case assessment analysis; surveys of foster carers, program workers and other stakeholders in the sector; and both focus groups and individual interviews with foster care workers. The evaluation found that the Circle Program lessened the number of unplanned exits of children from foster placements compared with generalist foster care. Another important finding was that the Circle Program positively influenced foster carers' decisions to stay in the carer role. Key components perceived as contributing to outcomes of the Circle Program included enhanced training of foster carers, intensive carer support, specialist therapeutic support to the child and carer, therapeutic service to family members and a network of services to provide support to the child. 相似文献
146.
Infants are readily able to use their recent experience to shape their future behavior. Recent work has confirmed that infants generate neural predictions based on their recent experience (Emberson, Richards, & Aslin, 2015) and that neural predictions trigger visual system activity similar to that elicited by visual stimulation. This study uses behavioral methods to ask, how visual is visual prediction? In Experiment 1, we confirmed that when additional trials provide additional visual experience with the experimental shape, infants exhibit a robust novelty preference. In Experiment 2, we removed the visual stimulus from some trials and presented the predictive auditory cue alone, allowing the effects of neural prediction to be assessed. We found no evidence of looking preferences at test, suggesting that visual prediction does not contribute to the computation of visual familiarity. In Experiment 3, we provided infants with a degraded visual stimulus to test whether visual prediction could bias visual perception under ambiguous conditions. Again, we found no evidence of looking preferences at test, suggesting that visual prediction is not biasing perception of an uncertain stimulus. Overall, our results suggest that visual prediction is not visual, in the strictest sense, despite the presence of visual system activation. 相似文献
147.
Mark E. Mitchell Stephen F. Matter Richard D. Durtsche Ishi Buffam 《Urban Ecosystems》2017,20(5):1121-1133
Green roofs are emerging engineered ecosystems that provide multiple benefits, but many are constructed with nutrient-rich substrate and have been found to leach out high levels of phosphorus (P) in runoff. It is unclear, however, how long green roofs act as sources of P or what mechanisms are responsible for these net losses. We measured P concentrations in runoff water over 4 years from a 1–5 year old extensive green roof in Cincinnati, OH, USA, produced a model to predict runoff P levels into the future, and validated predictions using runoff from 2 nearby extensive green roofs. P concentrations in runoff from the focal green roof were on par with heavily fertilized agroecosystems and displayed strong seasonal dynamics and a rapid decline over the 4-year study. Runoff measurements and changes in substrate P content over a 2-year period were used to estimate a mass balance for green roof P. P loss from the substrate was substantial (4.55 ± 2.3 g P/m2/yr), but only a small portion of the loss was attributable to leaching of P in runoff (0.19–0.65 g P/m2/yr). Missing P may be attributed to a combination of plant uptake and altered P form and binding strength, but further research is needed to precisely identify the mechanisms of P depletion. Our results also suggest that these and similar extensive green roofs are likely to act as environmentally significant sources of P for 10 or more years following roof installation, highlighting the need for reductions in initial substrate P content. 相似文献
148.
Steve Geoffrion Jane Goncalves Josette Sader Richard Boyer André Marchand 《Journal of workplace behavioral health》2017,32(3):172-189
Investigations into workplace aggression (WPA) remain largely occupation specific, with few studies using a comparative approach. The aim of the present study was to compare the health care, law enforcement, and public transportation sectors with regards to the prevalence of different types of WPA, the perceptions of workers toward WPA, and the psychological consequences of such acts. A cross-sectional survey was completed by 1,774 workers in Canada. Multinomial regressions were utilized to address the objectives. Findings revealed that verbal abuse victimization was particularly common in bus drivers, witnessing death threats was most frequent among law enforcement officials, and witnessing all types of WPA was most common among health care workers. Although bus drivers did not normalize WPA, they feared complaining about violence to their employer and thought it useless to talk it about unless wounds were visible. Fear of complaining about violence to colleagues was prevalent in health care and law enforcement, both sectors in which WPA was normalized. Finally, flashbacks and irritability following WPA were most likely to affect bus drivers whereas health care workers experienced hypervigilance to a greater extent. Strategies to tailor primary, secondary, and tertiary prevention according to these distinctions are suggested to offer a better-informed response to WPA. 相似文献
149.
“Friendly” Initiatives: An Emerging Approach to Improve Communities for Vulnerable Populations 总被引:2,自引:1,他引:1
A growing number of cities and towns are implementing “friendly” initiatives to change the community’s social and physical infrastructure to address the needs of a particular vulnerable segment of their population. Three prominent examples are aging-friendly, child-friendly, and immigrant-friendly initiatives. Although the limited but growing literature describes these initiatives as promising strategies to improve the quality of life of the targeted population, to date there has been little written about the underlying goals, values, and assumptions of these efforts. Using the value-critical approach, this article aims to better understand these aspects of population-friendly initiatives by examining the scholarly and grey literature. Social workers engaged in community and policy practice can play a key role in these efforts and call attention to the ways they may alleviate or exacerbate inequities. Future research is needed to assess the effects of these initiatives on their targeted population as well as other community residents. 相似文献
150.
Objectives: Based on the premise that internalized homonegativity (IH) is a product of the incorporation of environmental heterosexism, the authors examined the influence of sociopolitical and individual influences on IH. Methods: The cross-sectional study consisted of 109,382 gay and bisexual men across 77 countries. Results: Variables at the (European) country-level that were associated with higher levels of IH included lack of laws recognizing same-sex relationships and perceived and actual negative gay-related public opinion about homosexuals. Individual-level variables significantly associated with IH were public opinion about homosexuals and exposure to gay-related victimization/discrimination. Conclusions: An improved sociopolitical climate for LGB individuals is needed. 相似文献