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111.
This paper presents a method of estimating a receiver operating characteristic (ROC) curve when the underlying diagnostic variable X is continuous and fully observed. The new method is based on modelling the probability of response given X , rather than the distribution of X given response. The method offers advantages in modelling flexibility and computational simplicity. The resulting ROC curve estimates are semi-parametric and can, in principle, take an infinite variety of shapes. Moreover, model selection can be based on standard methods within the binomial regression framework. Statistical accuracy of the curve estimate is provided by a simply implemented bootstrap approach.  相似文献   
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Summary.  We define residuals for point process models fitted to spatial point pattern data, and we propose diagnostic plots based on them. The residuals apply to any point process model that has a conditional intensity; the model may exhibit spatial heterogeneity, interpoint interaction and dependence on spatial covariates. Some existing ad hoc methods for model checking (quadrat counts, scan statistic, kernel smoothed intensity and Berman's diagnostic) are recovered as special cases. Diagnostic tools are developed systematically, by using an analogy between our spatial residuals and the usual residuals for (non-spatial) generalized linear models. The conditional intensity λ plays the role of the mean response. This makes it possible to adapt existing knowledge about model validation for generalized linear models to the spatial point process context, giving recommendations for diagnostic plots. A plot of smoothed residuals against spatial location, or against a spatial covariate, is effective in diagnosing spatial trend or co-variate effects. Q – Q -plots of the residuals are effective in diagnosing interpoint interaction.  相似文献   
114.
The completely random character of radioactive disintegration provides the basis of a strong justification for a Poisson linear model for single-photon emission computed tomography data, which can be used to produce reconstructions of isotope densities, whether by maximum likelihood or Bayesian methods. However, such a model requires the construction of a matrix of weights, which represent the mean rates of arrival at each detector of photons originating from each point within the body space. Two methods of constructing these weights are discussed, and reconstructions resulting from phantom and real data are presented.  相似文献   
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A nationally representative sample of respondents estimated their fatality risks from four types of natural disasters, and indicated whether they favored governmental disaster relief. For all hazards, including auto accident risks, most respondents assessed their risks as being below average, with one-third assessing them as average. Individuals from high-risk states, or with experience with disasters, estimate risks higher, though by less than reasonable calculations require. Four-fifths of our respondents favor government relief for disaster victims, but only one-third do for victims in high-risk areas. Individuals who perceive themselves at higher risk are more supportive of government assistance.  相似文献   
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This study examined the unique and interactive roles of mother and teacher depressive symptoms in child adjustment in 277 African American single mother‐headed families, as well as whether the associations differed depending on the age and gender of the child. Findings revealed a significant association between maternal depressive symptoms and child depressive symptoms in girls, but not boys. Moreover, the combination of higher levels of both mother and teacher depressive symptoms was associated with the highest level of child depressive symptoms and, for younger children, externalizing symptoms. The importance of considering the multiple social contexts in which children interact is discussed.  相似文献   
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The aim of the study was to explore the degree (and type) of burnout and trauma symptoms, personal histories and coping strategies retrospectively reported by those who work with maltreated children and their families. A self‐selected sample of workers (N = 44) completed a self‐report questionnaire assessing childhood maltreatment, family background characteristics, current adjustment, coping strategies and burnout. Workers reported high levels of emotional exhaustion and depersonalization, and a low to moderate sense of personal accomplishment. Family background characteristics predicted the occurrence of maltreatment and current adjustment, and a personal history of maltreatment predicted current trauma symptoms, but not burnout. Workers most frequently used problem‐focused coping strategies and sought social support; however, coping strategies were not associated with the level of either trauma symptoms or burnout. Despite employing positive coping strategies, their efficacy may be affected by other interpersonal, intra‐individual and job resource issues. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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