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211.
Editorial     
Journal of Nonverbal Behavior -  相似文献   
212.
Microscale chemistry is appealing to all levels of education.In contrast to conventional macroscale chemistry,only minute amount of chemicals are required to undertaking a chemical investigation.  相似文献   
213.
Abstract

Objective: This study explored the potential relationships between existing media and health apps for health information among college students. Participants: This study collected and analyzed a total of 408 surveys from students of 7 universities across the United States. Methods: In order to explore the research questions and test the hypotheses, quantitative data from the online survey were analyzed through hierarchical regression analyses. Results: Results from the hierarchical regression analyses indicated that the perceived credibility of health information from traditional mass media was positively and significantly associated with college students' perception of health apps. However, there was no significant effect in regards to online media. Conclusions: This study's consideration of the relationships between existing media and health apps may guide health practitioners in their strategic approaches to improve the well-being of college students.  相似文献   
214.
Two ways of modelling overdispersion in non-normal data   总被引:2,自引:0,他引:2  
For non-normal data assumed to have distributions, such as the Poisson distribution, which have an a priori dispersion parameter, there are two ways of modelling overdispersion: by a quasi-likelihood approach or with a random-effect model. The two approaches yield different variance functions for the response, which may be distinguishable if adequate data are available. The epilepsy data of Thall and Vail and the fabric data of Bissell are used to exemplify the ideas.  相似文献   
215.
The quasilikelihood estimator is widely used in data analysis where a likelihood is not available. We illustrate that with a given variance function it is not only conservative, in minimizing a maximum risk, but also robust against a possible misspecification of either the likelihood or cumulants of the model. In examples it is compared with estimators based on maximum likelihood and quadratic estimating functions.  相似文献   
216.
Lee S  Zou F  Wright FA 《Annals of statistics》2010,38(6):3605-3629
A number of settings arise in which it is of interest to predict Principal Component (PC) scores for new observations using data from an initial sample. In this paper, we demonstrate that naive approaches to PC score prediction can be substantially biased towards 0 in the analysis of large matrices. This phenomenon is largely related to known inconsistency results for sample eigenvalues and eigenvectors as both dimensions of the matrix increase. For the spiked eigenvalue model for random matrices, we expand the generality of these results, and propose bias-adjusted PC score prediction. In addition, we compute the asymptotic correlation coefficient between PC scores from sample and population eigenvectors. Simulation and real data examples from the genetics literature show the improved bias and numerical properties of our estimators.  相似文献   
217.
A heated debate about battered women who kill abusive male partners started in the 1970s. In this study, we tracked the public discourse on battered women who kill by coding 250 newspaper articles published between 1978 and 2002. Using four typifying models, we found that leading explanations for why battered women kill medicalized then criminalized their actions; they were mad then bad. We also found that reporters used quotes from claims makers supporting conventional or medical typifications of battered women to a much greater degree than statements from alternative, feminist sources. In conclusion, simplified, sensational and conventional understandings of crime causation drove the social construction of “the battered woman who kills”. She may be mad or bad, but rarely has she been portrayed as reasonable. Suggestions for promoting feminist narrative in the media are also provided.  相似文献   
218.
For a two variance component mixed linear model, it is shown that under suitable conditions there exists a nonlinear unbiased estimator that is better than a best linear unbiased estimator defined with respect to a given singular covariance matrix. It is also shown how this result applies to improving on intra-block estimators and on estimators like the unweighted means estimator in a random one-way model.  相似文献   
219.
The current analysis was designed to critically examine the tendency to focus on child maltreatment as a unique risk factor and test the resulting assumption of a direct causal relationship between early maltreatment and later behavioral problems. The variation seen in behavioral outcomes among children reported for maltreatment early in life led us to hypothesize that the cumulative level of risk facing children and their families can, at least in part, account for that variation in outcome. Participants were 242 mothers of predominantly at-risk newborn infants who were interviewed shortly after giving birth. The State Central Registry of Maltreatment was then reviewed over each child's first four years of life to assess for early maltreatment. Following the neonatal interviews, mothers completed the Child Behavior Checklist when their children were 4, 6, 8, 10 and 12 years-of-age. Although early maltreatment report does appear to be important to early child functioning, the cumulative level of risk more strongly predicts long-term clinical behavioral difficulty. High-risk children who were not reported for maltreatment by age 4 demonstrate greater behavioral problem trajectories than did low-risk children with a maltreatment report. Maltreatment itself may be best conceptualized as an important, but not singularly so, risk factor for later behavioral problems. In focusing directly on reported maltreatment, our child protective systems may be paying too little attention to what else is going wrong in the lives of children and targeting intervention efforts in the wrong direction. When it comes to early maltreatment our child protective policy and practice need to broaden their lenses to include greater emphasis on overall family functioning, stress and well-being. Early maltreatment, it seems, may be a symptom of more profound problems in the early environments of our most vulnerable children, rather than the problem itself.  相似文献   
220.
Recently, the orthodox best linear unbiased predictor (BLUP) method was introduced for inference about random effects in Tweedie mixed models. With the use of h-likelihood, we illustrate that the standard likelihood procedures, developed for inference about fixed unknown parameters, can be used for inference about random effects. We show that the necessary standard error for the prediction interval of the random effect can be computed from the Hessian matrix of the h-likelihood. We also show numerically that the h-likelihood provides a prediction interval that maintains a more precise coverage probability than the BLUP method.  相似文献   
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