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51.
Gambling studies have described a “near-miss effect” wherein the experience of almost winning increases gambling persistence. The near-miss has been proposed to inflate the value of preceding actions through its perceptual similarity to wins. We demonstrate here, however, that it acts as a conditioned stimulus to positively or negatively influence valuation, dependent on reward expectation and cognitive engagement. When subjects are asked to choose between two simulated slot machines, near-misses increase valuation of machines with a low payout rate, whereas they decrease valuation of high payout machines. This contextual effect impairs decisions and persists regardless of manipulations to outcome feedback or financial incentive provided for good performance. It is consistent with proposals that near-misses cause frustration when wins are expected, and we propose that it increases choice stochasticity and overrides avoidance of low-valued options. Intriguingly, the near-miss effect disappears when subjects are required to explicitly value machines by placing bets, rather than choosing between them. We propose that this task increases cognitive engagement and recruits participation of brain regions involved in cognitive processing, causing inhibition of otherwise dominant systems of decision-making. Our results reveal that only implicit, rather than explicit strategies of decision-making are affected by near-misses, and that the brain can fluidly shift between these strategies according to task demands.  相似文献   
52.
The researchers examined differential outcomes related to two distinct motivations for withdrawal (preference for solitude and shyness) as well as the possibility that support from important others (mothers, fathers, and best friends) attenuate any such links. Adolescents (159 males, 171 females) reported on their motivations to withdraw, internalizing symptoms, and relationship quality in eighth grade, as well as their anxiety and depression in ninth grade. Using structural equation modeling, the authors found that maternal support weakened the association between shyness and internalizing problems; friend support weakened the association between preference for solitude and depression; and friend support strengthened the association between shyness and depression. Results suggest that shy adolescents may not derive the same benefits from supportive friendships as their typical peers.  相似文献   
53.
Multivariate control charts are used to monitor stochastic processes for changes and unusual observations. Hotelling's T2 statistic is calculated for each new observation and an out‐of‐control signal is issued if it goes beyond the control limits. However, this classical approach becomes unreliable as the number of variables p approaches the number of observations n, and impossible when p exceeds n. In this paper, we devise an improvement to the monitoring procedure in high‐dimensional settings. We regularise the covariance matrix to estimate the baseline parameter and incorporate a leave‐one‐out re‐sampling approach to estimate the empirical distribution of future observations. An extensive simulation study demonstrates that the new method outperforms the classical Hotelling T2 approach in power, and maintains appropriate false positive rates. We demonstrate the utility of the method using a set of quality control samples collected to monitor a gas chromatography–mass spectrometry apparatus over a period of 67 days.  相似文献   
54.
This paper reports on the findings from a qualitative study into the experiences of parents who were involved in the English child protection system in 2013. Seventeen in‐depth interviews were conducted involving 19 parents and/or partners, and a framework approach was used to analyse the data. There were positive experiences of individual social workers and some positive experiences of the child protection system. However, the overwhelming theme of the parents' experiences was that the system was uncaring, inflexible and for some harmful to both themselves and their children. Despite being included in the child protection process, parents felt they were not afforded the same rights as a participant, as a decision‐maker or as a partner in seeking to improve the situation. The threat of consequences silenced parents who felt unable to speak out or challenge the things they disagreed with or coerced others into signing agreements they did not agree to. Such experiences related to a sense that they were being treated as ‘less than human’. These findings are considered within the context of recent reforms within the English child protection system.  相似文献   
55.
Objective: The purpose of this pilot study was to evaluate the Resilience and Coping Intervention (RCI) with college students. Participants: College students (aged 18–23) from a large Midwest US university who volunteered for a randomized controlled trial during the 2015 spring semester. Methods: College students were randomly assigned to an intervention (n = 64) or a control (n = 65) group. Intervention participants received three 45-minute RCI sessions over subsequent weeks. All participants completed pre- and post-intervention assessments at the beginning of Week 1 and end of Week 3. Student resilience, coping, hope, stress, depression, and anxiety were assessed. Results. RCI participants reported significantly more hope and less stress and depression from Week 1 to Week 3 compared with control participants. Results for resilience also approached statistical significance. Effect sizes were small to moderate. Conclusions: This study found preliminary evidence that RCI is an effective resilience intervention for use with college students.  相似文献   
56.
This article examines gambling harms from both gamblers and affected others’ perspectives. Participants (3076 gamblers and 2129 affected others) completed a retrospective survey that elicited information on harms they experienced from gambling across their lifetime. Their responses were analyzed through testing measurement invariance, estimating item-response theoretic parameters, calculating percentages, confidence intervals, and correlations, as well as regressions. The results indicated large commonalities in the experience of harms reported by gamblers and affected others. Further, gamblers appeared to ‘export’ about half of the harms they experienced to those around them. The findings also provided detailed profiles of evolving harms as problem gambling severity varies.  相似文献   
57.
ABSTRACT

Residential care is one of the most restrictive out-of-home care settings; however, this is a temporary placement and youth eventually reintegrate into the home and community setting. Reintegration presents many challenges, and aftercare becomes critical for maintaining youth gains and promoting family stability. Aftercare programs and supports should align to individual family needs that entail understanding individual and familial characteristics. Previous studies have explored characteristics related to family functioning, mental health, behavior, and perceptions of need during reintegration; yet little is known regarding how affective characteristics (i.e., self-efficacy, empowerment) factor into reintegration, or the implications this may have for providers. The purpose of this study was to address this gap by exploring empowerment and self-efficacy in caregivers (= 120) who had a child return home within 1 month of departing residential care. Overall, caregivers reported high levels of empowerment and self-efficacy during the initial transition period. Significant differences for empowerment and self-efficacy were present in characteristics such as race, income, number of children in the home, and free/reduced lunch status.  相似文献   
58.
This research was motivated by our goal to design an efficient clinical trial to compare two doses of docosahexaenoic acid supplementation for reducing the rate of earliest preterm births (ePTB) and/or preterm births (PTB). Dichotomizing continuous gestational age (GA) data using a classic binomial distribution will result in a loss of information and reduced power. A distributional approach is an improved strategy to retain statistical power from the continuous distribution. However, appropriate distributions that fit the data properly, particularly in the tails, must be chosen, especially when the data are skewed. A recent study proposed a skew-normal method. We propose a three-component normal mixture model and introduce separate treatment effects at different components of GA. We evaluate operating characteristics of mixture model, beta-binomial model, and skew-normal model through simulation. We also apply these three methods to data from two completed clinical trials from the USA and Australia. Finite mixture models are shown to have favorable properties in PTB analysis but minimal benefit for ePTB analysis. Normal models on log-transformed data have the largest bias. Therefore we recommend finite mixture model for PTB study. Either finite mixture model or beta-binomial model is acceptable for ePTB study.  相似文献   
59.
To assess the employment opportunities of older job-changers in the years prior to retirement, this study examines the how the breadth of occupations in which they find employment narrows as they age past their prime working years and how this differs by gender and educational attainment. The results indicate that workers who change jobs in their early 50s find employment in a reasonably similar set of occupations as prime-age workers, with opportunities narrowing at older ages. They also indicate that job opportunities broadened significantly for better-educated older workers since the late 1990s. While job opportunities now narrow significantly for less-educated men in their late 50s, this narrowing primarily occurs in the early 60s for women and better-educated men. In contrast to previous research, the study finds that employer policies that emphasize hiring from within are less important barriers to the hiring of older job-seekers. The study also finds that the narrowing of job opportunities is associated with a general decline in job quality as measured by median occupational earnings, a decline associated with differences in occupational skill requirements and the underlying economic environment. These results suggest that older hiring is not as limited to a select few occupations as it had been in previous decades, and that policy reforms aimed at increasing opportunities and improving labor market fluidity might best be served if they focused on less-educated men.  相似文献   
60.
In this article, we examine birth cohort differences in parents’ provision of monetary help to adult children with particular focus on the extent to which cohort differences in family structure and the transition to adulthood influence these changes. Using data from the Health and Retirement Study from 1994 to 2010, we compare financial help to children of three respondent cohorts as the parents in these birth cohorts from ages 53–58 to 57–62. We find that transfers to children have increased among more recent cohorts. Two trends—declining family size and children’s delay in marriage—account for part of the increase across cohorts. However, other trends, such as the increase in the number of stepchildren and increasing child’s income level, tend to decrease the observed cohort trend.  相似文献   
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