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961.
Young adulthood is a period renowned for engagement in impulsive and risky behaviors, including gambling. There are some indications that young adults exhibit higher gambling rates in comparison to older adults. Problem gambling has also been linked to ADHD. This longitudinal study examines the relationship between gambling and ADHD among an epidemiological sample of young adults (n = 235; males = 179, females = 56) aged 18-24. Results indicate that individuals who report childhood ADHD symptoms which persist into young adulthood experience greater gambling problem severity than participants with no ADHD or those with non-persistent ADHD.  相似文献   
962.
Few studies have examined the influence of environmental factors on children's executive functioning (EF) performance. The present study examined the effects of a punitive vs. non‐punitive school environment on West African children's EF skills. Tasks included a ‘cool’ (relatively non‐affective) and ‘hot’ (relatively affective/motivational) version of three EF tasks: delay of gratification; gift delay; and dimensional change card sort. Children had more difficulties with the hot versions of the tasks than the cool versions, and older children outperformed younger children. After controlling for verbal ability (Peabody picture vocabulary test‐third edition), a consistent pattern of interaction between school and grade level emerged. Overall, kindergarten children in the punitive school performed no differently than their counterparts in the non‐punitive school. However, in grade 1, children in the punitive school performed significantly worse than their counterparts in the non‐punitive school. These results point to the need to consider interactions among discipline style, age, and internalization processes of self‐regulation to better understand environmental influences on EF development.  相似文献   
963.
We propose the use of signal detection theory (SDT) to evaluate the performance of both probabilistic forecasting systems and individual forecasters. The main advantage of SDT is that it provides a principled way to distinguish the response from system diagnosticity, which is defined as the ability to distinguish events that occur from those that do not. There are two challenges in applying SDT to probabilistic forecasts. First, the SDT model must handle judged probabilities rather than the conventional binary decisions. Second, the model must be able to operate in the presence of sparse data generated within the context of human forecasting systems. Our approach is to specify a model of how individual forecasts are generated from underlying representations and use Bayesian inference to estimate the underlying latent parameters. Given our estimate of the underlying representations, features of the classic SDT model, such as the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC), follow immediately. We show how our approach allows ROC curves and AUCs to be applied to individuals within a group of forecasters, estimated as a function of time, and extended to measure differences in forecastability across different domains. Among the advantages of this method is that it depends only on the ordinal properties of the probabilistic forecasts. We conclude with a brief discussion of how this approach might facilitate decision making.  相似文献   
964.
This article deals with the extent to which consulting research and consulting practice are pulling in the same direction or whether the gap between them still seems insurmountable. Therefore we examine the literature on consulting research, report what kind of research coaching practitioners would consider beneficial and introduce first findings from an empirical survey in which coaching practitioners were asked about their motivation for—or against—taking part in coaching research.  相似文献   
965.
Les auteures analysent le concept du «choix>> dans le travail des aidants naturels filiaux. Dans la documentation théorique et empirique sur le travail des aidants naturels, une dichotomie entre le «choix>> et l'«obligation>> est considérée comme une construction sociale. Néanmoins, cette dichotomie ne reflète pas adéquatement les expériences familiales de fourniture de soins; par exemple, le choix et l'obligation ne constituent pas des motivations mutuellement exclusives. Ils sont plutôt «relationnels>>, «contextuels>> et manifestes dans l'interaction entre des macro et des microcontextes. La dichotomie choix-obligation est également idéologique. Sur le plan de la politique morale, elle fait la promotion du déchargement de la responsabilité des gouvernements sur les familles, elle obscurcit la complexité des relations filiales et peut même promouvoir l'ambivalence psychologique.
In this paper, we discuss the concept of "choice" in filial care work. A dichotomy between choice and obligation is constructed in theoretical and empirical literature on filial care work. However, this dichotomy does not adequately reflect family caregiving experiences; for instance, choice and obligation are not mutually exclusive motivations. Rather, choice and obligation are "relational" and "contextual" and manifest in the interaction between macro- and micro-contexts. The choice-obligation dichotomy is also ideological. At the moral-political level, it promotes the downloading of responsibility by governments to family, obscures the complexity of filial relationships, and may even promote psychological ambivalence.  相似文献   
966.
967.
We develop a mathematical optimization model at the intersection of homeland security and immigration, that chooses various immigration enforcement decision variables to minimize the probability that a terrorist can successfully enter the United States across the U.S.-Mexico border. Included are a discrete choice model for the probability that a potential alien crosser will attempt to cross the U.S.-Mexico border in terms of the likelihood of success and the U.S. wage for illegal workers, a spatial model that calculates the apprehension probability as a function of the number of crossers, the number of border patrol agents, and the amount of surveillance technology on the border, a queueing model that determines the probability that an apprehended alien will be detained and removed as a function of the number of detention beds, and an equilibrium model for the illegal wage that balances the supply and demand for work and incorporates the impact of worksite enforcement. Our main result is that detention beds are the current system bottleneck (even after the large reduction in detention residence times recently achieved by expedited removal), and increases in border patrol staffing or surveillance technology would not provide any improvements without a large increase in detention capacity. Our model also predicts that surveillance technology is more cost effective than border patrol agents, which in turn are more cost effective than worksite inspectors, but these results are not robust due to the difficulty of predicting human behavior from existing data. Overall, the probability that a terrorist can successfully enter the United States is very high, and it would be extremely costly and difficult to significantly reduce it. We also investigate the alternative objective function of minimizing the flow of illegal aliens across the U.S.-Mexico border, and obtain qualitatively similar results.  相似文献   
968.
Peer interaction is an important component of children's social repertoires that is associated with a variety of developmental outcomes and life skills. The present study provides an in‐depth study of early dyadic peer behaviors during the infancy period, during which social competence with peers is first being developed. Results from variable‐centered analyses highlight the effectiveness of behaviors, such as offering objects to peers, and point to the importance of the social context set by a peer's prior social behavior and processes for eliciting peer responses. Findings from person‐centered analyses reveal marked individual differences in the processes through which infants are successful in eliciting responses from their peers, illustrating the presence of multiple pathways to achieving social competence with peers.  相似文献   
969.
We use a sample of CEO appointments at US corporations over the years 1992–2004 to test the 'glass cliff' hypothesis, which posits that females are appointed to leadership positions at firms that are in a precarious financial condition. Our analysis utilizes three measures of stock-price-based financial performance and two distinct control samples of appointments of males to the CEO position. We find that corporate performance preceding CEO appointments tends to favor females, implying that females (males) are appointed to the CEO position largely at times when the firm is in relatively better (worse) financial health. Disaggregating the data by appointments in up versus down markets, at high-risk versus low-risk firms, and by calendar time yield similar conclusions. There appears to be no glass cliff facing female CEOs at US firms. Our findings suggest a need for additional research to identify where and for what types of positions this phenomenon is prevalent.  相似文献   
970.
This article provides an analysis of my personal experience and research on the need for sub-Saharan African economic transformation. It contains relevant references to econometric modeling which are consistent with this analysis. After presenting the causes of African failures, ranging from the alleged role of slavery and colonization, to trade composition and relative decline, to present day problems of governance, low level of foreign investment in Africa, and mass unemployment, the article concludes with an agenda for the transformation of sub-Saharan Africa.  相似文献   
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