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191.
This article provides a reanalysis of J. W. Johnson's (2000) “relative weights” method for assessing variable importance in multiple regression. The primary conclusion of the reanalysis is that the derivation of the method is theoretically flawed and has no more validity than the discredited method of Green, Carroll, and DeSarbo (1978) on which it is based. By means of 2 examples, supplemented by other results from the literature, it is also shown that the method can result in materially distorted inferences when it is compared with another widely used importance metric, namely, general dominance (Azen & Budescu, 2003; Budescu, 1993). Our primary recommendation is that J. W. Johnson's (2000) relative weights method should no longer be used as a variable importance metric for multiple linear regression. In the final section of the article, 2 additional recommendations are made based on our analysis, examples, and discussion.  相似文献   
192.
Cross‐situational word learning, like any statistical learning problem, involves tracking the regularities in the environment. However, the information that learners pick up from these regularities is dependent on their learning mechanism. This article investigates the role of one type of mechanism in statistical word learning: competition. Competitive mechanisms would allow learners to find the signal in noisy input and would help to explain the speed with which learners succeed in statistical learning tasks. Because cross‐situational word learning provides information at multiple scales—both within and across trials/situations—learners could implement competition at either or both of these scales. A series of four experiments demonstrate that cross‐situational learning involves competition at both levels of scale, and that these mechanisms interact to support rapid learning. The impact of both of these mechanisms is considered from the perspective of a process‐level understanding of cross‐situational learning.  相似文献   
193.
Abstract

Recent investigations suggest that the hostility component of the Type A behavior patter (TABP) is a greater detriment to health than the overall pattern. Some researchers suggest that certain Type A characteristics (e.g., job-involvement) are actually adaptive. This study compared the relative relationship of the TABP and hostility to career-related achievement and psychosocial adjustment among 223 service-delivery employees. Male and female participants completed the Jenkins Activity Survey and the MMPI Hostility Scale as part of a cardiovascular disease risk factor screening. The TABP was positively associated with managerial status for both men and women. However, the TABP was positively related to psychosocial adjustment variables among men only. Hostility was significantly related to undesirable outcomes including lower job status, life dissatisfaction, and unfavorable perceptions of the workplace for both men and women. Discussion addresses organizational factors which might perpetuate hostility and the TABP, as well as gender differences in the experience of these constructs.  相似文献   
194.
This study assessed the unique associations of risk perceptions and worry with attitudes about genetic testing for breast cancer susceptibility. Women (general practitioner clinic attenders, university students, and first-degree relatives of breast cancer survivors; N?=?303) read information about genetic testing and completed measures assessing perceived cancer risk, cancer worry, and genetic testing attitudes and beliefs. Worry was associated with greater interest in genetic testing, stronger beliefs that testing has detrimental emotional consequences, and positive beliefs about benefits of testing and risk-reducing surgeries. Perceived risk was unrelated to interest and associated with more skeptical beliefs about emotional consequences and benefits of testing and risk-reducing surgeries. At low worry levels, testing interest increased with more positive beliefs about testing benefits; at high worry levels, interest was high regardless of benefits beliefs. The findings support Leventhal's Common-Sense Model of self-regulation delineating interactive influences of risk-related cognitions and emotions on information processing and behavior.  相似文献   
195.
To develop a preoperative anxiety scale (YPAS) for children undergoing surgery, 21 specific behaviors indicating anxiety were defined within five domains (activity, emotional expressivity, state of arousal, vocalization, and use of adults). A reliability Kappa analysis revealed that inter-observer agreement ranged from .66 to .94, while intra-observer Kappa ranged from .66 to .91. Validity analysis between a Visual Analog Scale and the YPAS revealed an r of .59 for entering the operating room. Multiserial analysis comparing the YPAS to the Vernon Anxiety Scale ranged from .61 to .64. Showing good to excellent observer reliability and validity, the YPAS proves to be an appropriate tool for studying children's responses in preoperative settings. As such, the new assessment instrument should be of interest to clinical and research neuropsychologists who need to assess a child's anxiety level prior to the undertaking of a given surgical procedure.  相似文献   
196.
Ninety-four prenatally cocaine-exposed and 50 non-cocaine-exposed infants were enrolled at birth and seen at 3,6, and 12 months. Applying a recently developed model (Cicchetti&Nelson, 1994) produced four independent groups: those infants assessed at birth only (n=61), those returning for at least one (n=29) or two (n=15) assessments after birth, and those returning for all three (n=35). Among those infants having all follow-up assessments, cocaine-exposed infants showed significantly lower psychomotor performance on the Bayley Scales of Infant Development (BSID) than did non-exposed infants. Results approached statistical significance for mental development. Except for birthweight (cocaine-exposed infants weighed significantly less), none of a wide range of maternal, perinatal, or neurobehavioral demographic variables biased study results or the generalization of findings to the total sample from those who returned for all visits.  相似文献   
197.
198.
Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants’ and young children's visual environments and provide new and often unexpected insights about the visual world from a child's point of view. The challenge in using head cameras is principally conceptual and concerns the match between what these cameras measure and the research question. Head cameras record the scene in front of faces and thus answer questions about those head-centered scenes. In this “Tools of the Trade” article, we consider the unique contributions provided by head-centered video, the limitations and open questions that remain for head-camera methods, and the practical issues of placing head cameras on infants and analyzing the generated video.  相似文献   
199.
Human visual object recognition is multifaceted and comprised of several domains of expertise. Developmental relations between young children's letter recognition and their 3-dimensional object recognition abilities are implicated on several grounds but have received little research attention. Here, we ask how preschoolers' success in recognizing letters relates to their ability to recognize 3-dimensional objects from sparse shape information alone. Seventy-three 2 1/2 to 5-year-old children completed a “Letter Recognition” task, measuring the ability to identify a named letter among 3 letters, and a “Shape Caricature Recognition” task, measuring recognition of familiar objects from sparse, abstract information about their part shapes and the spatial relations among those parts. Children also completed a control “Shape Bias” task, in which success depends on matching exact shapes but not on building an internal representation of the configuration of features characteristic of an object category or letter. Children's success in letter recognition was positively related to their shape caricature recognition scores, but not to their shape bias scores. The results suggest that letter recognition builds upon developing skills in attending to and representing the relational structure of object shape, and that these skills are common to both 2-dimensional and 3-dimensional object perception.  相似文献   
200.
Each year, 14,000 children are diagnosed with cancer in the United States. Prolonged, intensive treatment regimens disrupt the entire family system, but effects on siblings are poorly understood. In this preliminary investigation, we employed a risk and resistance framework to study adjustment among 30 siblings (aged 10–17) of children undergoing cancer treatment. We examined whether or not objective stress associated with the cancer experience (contextual threat) predicted sibling distress and explored demographic and disease-related predictors of sibling adjustment. Contextual threat was positively associated with sibling-reported distress, independent of sibling age, gender, birth order relative to the child with cancer, and cancer treatment intensity. From among the demographic and disease-related factors, only younger birth order relative to the child with cancer was independently associated with sibling distress. These results suggest that a subset of siblings may be at increased risk for elevated distress in the face of their brother’s or sister’s illness.  相似文献   
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