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931.
Methodologists have developed mediation analysis techniques for a broad range of substantive applications, yet methods for estimating mediating mechanisms with missing data have been understudied. This study outlined a general Bayesian missing data handling approach that can accommodate mediation analyses with any number of manifest variables. Computer simulation studies showed that the Bayesian approach produced frequentist coverage rates and power estimates that were comparable to those of maximum likelihood with the bias-corrected bootstrap. We share an SAS macro that implements Bayesian estimation and use 2 data analysis examples to demonstrate its use.  相似文献   
932.
933.
This study examines youth initiated mentoring (YIM), a new approach to mentoring in which youth nominate mentors from among the non-parental adults within their existing social networks (e.g., teachers, family friends, extended family members). YIM is currently being implemented through the National Guard Youth ChalleNGe Program (NGYCP), an intensive residential intervention program for youth ages 16–18 who have dropped out or been expelled from high school. This study employed a mixed methods explanatory design, drawing on quantitative data from a national longitudinal evaluation of NGYCP (N = 1,173) and qualitative data from a subsample of participants (N = 30) in the evaluation. Results indicated that more enduring mentoring relationships were associated with increased retention of educational, vocational, and behavioral outcomes 3 years following entry into the study. Qualitative data suggested that, when relationships endured, mentors contributed to improvements in participants’ educational and occupational success, quality of relationships with parents, peers, and others, and self-concept by providing social-emotional support, instrumental support, and guidance. Results also revealed that relationships were more likely to endure when youth chose their mentors on their own (rather than receiving help from parents or program staff) and when mentors were of the same race as youth. Implications for research and practice are discussed.  相似文献   
934.
We examined reading comprehension in children with ADHD by assessing their ability to build a coherent mental representation that allows them to recall central and peripheral information. We compared children with ADHD (mean age 9.78) to word reading-matched controls (mean age 9.89) on their ability to retell a passage. We found that even though children with ADHD recalled more central than peripheral information, they showed their greatest deficit, relative to controls, on central information—a centrality deficit (Miller and Keenan, Annals of Dyslexia 59:99–113, 2009). We explored the cognitive underpinnings of this deficit using regressions to compare how well cognitive factors (working memory, inhibition, processing speed, and IQ) predicted the ability to recall central information, after controlling for word reading ability, and whether these cognitive factors interacted with ADHD symptoms. Working memory accounted for the most unique variance. Although previous evidence for reading comprehension difficulties in children with ADHD have been mixed, this study suggests that even when word reading ability is controlled, children with ADHD have difficulty building a coherent mental representation, and this difficulty is likely related to deficits in working memory.  相似文献   
935.
Punitive public attitudes cannot be easily explained by pointing to instrumental concerns (e.g., fear of crime, personal victimization, or real or perceived levels of crime). Instead, numerous observers have suggested that public punitiveness is more a symptom of free-floating anxieties and insecurities resulting from social change than a rational response to crime problems. We argue that these public concerns might be better understood by drawing on the insights of psychoanalytic theory, and we review relevant theoretical work to that effect.  相似文献   
936.
To explore the relationship between neurogenic bladder management techniques and quality of life (QoL) among individuals with spinal cord injury (SCI). A key terms literature search was conducted in multiple electronic databases (i.e., MEDLINE, CINAHL, EMBASE, and PsycINFO). Studies published up to and including May 2013 were reviewed and evaluated based on the following criteria: (1) full-length journal article published in the English language; (ii) human subjects ≥18 years; (iii) ≥?50 % of subjects had a SCI; (iv) results on QoL, as it related to bladder management method, were reported for at least three subjects. A total of 422 articles were extracted and upon review of titles and abstracts, 7 studies met the inclusion criteria. There were two level 2 cohort studies and five level 5 observational studies. Sample sizes ranged from 37 to 282 with an average of 117.1 individuals per study. All participants were at least six months post injury. Bladder management methods used included intermittent (patient/attendant), indwelling (suprapubic/transurethral), and condom catheterization, micturition assistive maneuvers, and electrical stimulation. Normal voiders scored better in all QoL measure domains compared to other management methods. Those using attendant intermittent and indwelling catheterization scored the poorest on the domains Personal Relationships, Emotions, and Mental Health. There is insufficient evidence to provide a definite conclusion as to the relationship between bladder management methods and QoL post SCI. However, individuals relying on others to aid in voiding may experience lower QoL compared to those who are independent.  相似文献   
937.
A popular procedure for investigating working memory processes has been the visual change-detection procedure. Models of performance based on that procedure, however, tend to be based on performance accuracy and treat working memory search as a one-step process, in which memory representations are compared to a test probe to determine if a match is present. To gain a clearer understanding of how search of these representations operate in the change-detection task, we examined reaction time in two experiments, with a single-item probe either located centrally or at the location of an array item. Contrary to current models of visual working memory capacity, our data point to a two-stage search process: a fast first step to check for the novelty of the probe and, in the absence of such novelty, a second, slower step to search exhaustively for a match between the test probe and a memory representation. In addition to these results, we found that participants tended not to use location information provided by the probe that theoretically could have abbreviated the search process. We suggest some basic revisions of current models of processing in this type of visual working memory task.  相似文献   
938.
Assortative mating for adiposity, whereby levels of adiposity in romantic partners tend to be positively correlated, has implications for population health due to the combined effects of partners' levels of adiposity on fertility and/or offspring health. Although assortative preferences for cues of adiposity, whereby leaner people are inherently more attracted to leaner individuals, have been proposed as a factor in assortative mating for adiposity, there have been no direct tests of this issue. Because of this, and because of recent work suggesting that facial cues of adiposity convey information about others' health that may be particularly important for mate preferences, we tested the contribution of assortative preferences for facial cues of adiposity to assortative mating for adiposity (assessed from body mass index, BMI) in a sample of romantic couples. Romantic partners' BMIs were positively correlated and this correlation was not due to the effects of age or relationship duration. However, although men and women with leaner partners showed stronger preferences for cues of low levels of adiposity, controlling for these preferences did not weaken the correlation between partners' BMIs. Indeed, own BMI and preferences were uncorrelated. These results suggest that assortative preferences for facial cues of adiposity contribute little (if at all) to assortative mating for adiposity.  相似文献   
939.
940.
In the present study, we investigated the role of list composition in the testing effect. Across three experiments, participants learned items through study and initial testing or study and restudy. List composition was manipulated, such that tested and restudied items appeared either intermixed in the same lists (mixed lists) or in separate lists (pure lists). In Experiment 1, half of the participants received mixed lists and half received pure lists. In Experiment 2, all participants were given both mixed and pure lists. Experiment 3 followed Erlebacher’s (Psychological Bulletin, 84, 212–219, 1977) method, such that mixed lists, pure tested lists, and pure restudied lists were given to independent groups. Across all three experiments, the final recall results revealed significant testing effects for both mixed and pure lists, with no reliable difference in the magnitude of the testing advantage across list designs. This finding suggests that the testing effect is not subject to a key boundary condition—list design—that impacts other memory phenomena, including the generation effect.  相似文献   
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