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991.
Recent research reflects a growing awareness of the value of using structural equation models to analyze repeated measures data. However, such data, particularly in the presence of covariates, often lead to models that either fit the data poorly, are exceedingly general and hard to interpret, or are specified in a manner that is highly data dependent. This article introduces methods for developing parsimonious models for such data. The underlying technology uses reduced-rank representations of the variances, covariances and means of observed and latent variables. The value of this approach, which may be implemented using standard structural equation modeling software, is illustrated in an application study aimed at understanding heterogeneous consumer preferences. In this application, the parsimonious representations characterize systematic relationships among consumer demographics, attitudes and preferences that would otherwise be undetected. The result is a model that is parsimonious, illuminating, and fits the data well, while keeping data dependence to a minimum.  相似文献   
992.
The study of prediction bias is important and the last five decades include research studies that examined whether test scores differentially predict academic or employment performance. Previous studies used ordinary least squares (OLS) to assess whether groups differ in intercepts and slopes. This study shows that OLS yields inaccurate inferences for prediction bias hypotheses. This paper builds upon the criterion-predictor factor model by demonstrating the effect of selection, measurement error, and measurement bias on prediction bias studies that use OLS. The range restricted, criterion-predictor factor model is used to compute Type I error and power rates associated with using regression to assess prediction bias hypotheses. In short, OLS is not capable of testing hypotheses about group differences in latent intercepts and slopes. Additionally, a theorem is presented which shows that researchers should not employ hierarchical regression to assess intercept differences with selected samples.  相似文献   
993.
Services to families have traditionally been delivered in a medical model. This presents challenges including workforce shortages, lack of cultural diversity, lack of training in strength-based work, and difficulty in successfully engaging and retaining families in the therapy process. The system of care (SOC) effort has worked to establish formal roles for caregivers in SOC to improve services. This paper provides an example of one community's efforts to change the SOC by expanding the roles available to caregivers in creating systems change. It describes the model developed by Communities of Care (CoC), a SOC in Central Massachusetts, and its evolution over a 10 year period. First person accounts by system partners, caregivers hired into professional roles as well as a family receiving services, demonstrate how hiring caregivers at all levels can change systems and change lives, not only for those being served but for the caregiver/professionals doing the work. It also demonstrates, however, that change at the system level is incremental, takes time, and can be fleeting unless an ongoing effort is made to support and sustain those changes.  相似文献   
994.
In an eyetracking study, we examined whether readers use psychological essentialist reasoning and perspective taking online. Stories were presented in which an animal or an artifact was transformed into another animal (e.g., a donkey into a zebra) or artifact (e.g., a plate into a clock). According to psychological essentialism, the essence of the animal did not change in these stories, while the transformed artifact would be thought to have changed categories. We found evidence that readers use this kind of reasoning online: When reference was made to the transformed animal, the nontransformed term (“donkey”) was preferred, but the opposite held for the transformed artifact (“clock” was read faster than “plate”). The immediacy of the effect suggests that this kind of reasoning is employed automatically. Perspective taking was examined within the same stories by the introduction of a novel story character. This character, who was naïve about the transformation, commented on the transformed animal or artifact. If the reader were to take this character’s perspective immediately and exclusively for reference solving, then only the transformed term (“zebra” or “clock”) would be felicitous. However, the results suggested that while this character’s perspective could be taken into account, it seems difficult to completely discard one’s own perspective at the same time.  相似文献   
995.
Research suggests that attention is attracted to evolutionary threats (e.g., snakes) due to an evolved "fear-module" that automatically detects biological threats to survival. However, recent evidence indicates that non-evolutionary threats (e.g., guns) capture and hold attention as well, suggesting a more general "threat-relevance" mechanism that directs attentional resources toward any potential danger in the environment. The current research measured how selective attentional resources were influenced both by the type of threat (e.g., snake vs. gun) and by the context in which the threat was encountered. Participants were primed with either natural or human-made environments to assess how these contexts influence attention to evolutionary and non-evolutionary threats, as measured by a spatial-cueing task. The results indicate that whether biological or non-biological threats receive greater attentional processing is determined by the context in which they are encountered.  相似文献   
996.
The Positive and Negative Affect Schedule for Children (PANAS-C/P; child and parent versions) yield positive affect (PA) and negative affect (NA) scales that are clinically useful for identifying youth with anxiety and mood problems. Despite the advantages that item response theory (IRT) offers relative to classical test theory with respect to shortening test instruments, no studies to date have applied IRT methodology to the PANAS-C/P scales. In the present study, we thus applied IRT methodology using a school-based development sample (child sample: N = 799; parent sample: N = 553) and developed a shortened 5-item PA scale (joyful, cheerful, happy, lively, proud) and a 5-item NA scale (miserable, mad, afraid, scared, sad) for the sake of simultaneously increasing the assessment efficiency of the PANAS-C/P scales while improving the psychometric properties of the scales. The reduced PA and NA child scales classified relevant diagnostic groups in a separate clinic-referred validation sample (N = 662) just as well as the original PANAS-C child scales and may be used to help identify youth with internalizing disorders in need of mental health services.  相似文献   
997.
This study aimed to develop predictive models for real-life driving outcomes in older drivers. Demographics, driving history, on-road driving errors, and performance on visual, motor, and neuropsychological test scores at baseline were assessed in 100 older drivers (ages 65-89 years [72.7]). These variables were used to predict time to driving cessation, first moving violation, or crash. Using Cox proportional hazards regression models, significant individual predictors for driving cessation were greater age and poorer scores on Near Visual Acuity, Contrast Sensitivity, Useful Field of View, Judgment of Line Orientation, Trail Making Test-Part A, Benton Visual Retention Test, Grooved Pegboard, and a composite index of overall cognitive ability. Greater weekly mileage, higher education, and "serious" on-road errors predicted moving violations. Poorer scores from Trail Making Test-Part B or Trail Making Test (B-A) and serious on-road errors predicted crashes. Multivariate models using "off-road" predictors revealed (a) age and Contrast Sensitivity as best predictors for driving cessation; (b) education, weekly mileage, and Auditory Verbal Learning Task-Recall for moving violations; and (c) education, number of crashes over the past year, Auditory Verbal Learning Task-Recall, and Trail Making Test (B-A) for crashes. Diminished visual, motor, and cognitive abilities in older drivers can be easily and noninvasively monitored with standardized off-road tests, and performances on these measures predict involvement in motor vehicle crashes and driving cessation, even in the absence of a neurological disorder. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   
998.
Social self preservation theory asserts that situations high in social-evaluative threat elicit increases in cortisol, a hormone released by the hypothalamic-pituitary-adrenal axis. Most tests of the theory have examined threats associated with social evaluation of a performance. Two experiments examined the effects of threatened social evaluation of one's physique. In Experiments 1 (n?=?50) and 2 (n?=?40), participants allocated to an experimental (threat) condition had significantly higher post-manipulation cortisol than participants in a control (no threat) condition. In Experiment 1, perceptions of social-evaluative threat were significantly correlated with post-manipulation cortisol levels. These results suggest that the threatened social evaluation of one's body can activate the cortisol response. Women who frequently experience such threats may be at increased risk for a variety of health conditions associated with chronic cortisol exposure.  相似文献   
999.
1000.
Provoking police officers to kill oneself or "suicide by cop" (SBC) has received scholarly as well as public attention. The extent to which film representations of SBC reflect SBC in society in relation to danger, depression, and other features was assessed in this study. Data on cinematic portrayals of SBC are from 16 American films; corresponding data on SBC in the real world are taken from 19 empirical studies. While the demographic features of SBC in the real world are largely reflected in film, major differences exist on motivations and incident characteristics. Motives for cinematic SBC were unlike SBC in society, wherein, respectively, 0% vs. 35% had attempted suicide in the past, 6% vs. 47% were chronically depressed, and 77% vs. 7% had recently killed someone. Cinematic SBC events disproportionately involve murderous, dangerous persons who are not depressed, and their deaths convey a sense of justice. While such media distortions can be profitable and entertain the audience, they also contribute to public misunderstandings of the nature of deviance and hinder the development of effective suicide and violence prevention programs.  相似文献   
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