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261.
Interpreting the intentions of internet predators:an examination of online predatory behavior 总被引:1,自引:0,他引:1
Marcum CD 《Journal of child sexual abuse》2007,16(4):99-114
262.
Smink JD 《New directions for youth development》2007,(116):35-48, 10
In the United States and around the rest of the world, there is a renewed focus on ensuring that schools are providing students with the skills necessary to compete in the global economy. High-quality summer learning programs are an ideal vehicle to help students gain content knowledge and develop innovative skills: they provide time for individual exploration and hands-on, experiential opportunities that can instill a lifelong love of learning that carries into the classroom and the workforce. 相似文献
263.
Communities across the nation have become increasingly concerned about inhalant use and use of harmful legal products among youth because of increasing prevalence rates and deleterious health consequences from abusing these products. The increasing concern of communities about inhaling and ingesting legal products has been coupled with increasing awareness and concern about ability of youth to access and abuse a variety of other legal retail products. There are few examples of scientifically designed community prevention projects that seek to reduce youth abuse of such legal products. This article describes a community prevention trial that is designed to reduce sales of inhalants and other harmful legal products to youth and demonstrates how the retailer component of the trial can be rigorously evaluated. It also shows how data from youth purchase attempts can complement survey data from retailers. 相似文献
264.
In recent years, a variety of regression models, including zero-inflated and hurdle versions, have been proposed to explain the case of a dependent variable with respect to exogenous covariates. Apart from the classical Poisson, negative binomial and generalised Poisson distributions, many proposals have appeared in the statistical literature, perhaps in response to the new possibilities offered by advanced software that now enables researchers to implement numerous special functions in a relatively simple way. However, we believe that a significant research gap remains, since very little attention has been paid to the quasi-binomial distribution, which was first proposed over fifty years ago. We believe this distribution might constitute a valid alternative to existing regression models, in situations in which the variable has bounded support. Therefore, in this paper we present a zero-inflated regression model based on the quasi-binomial distribution, taking into account the moments and maximum likelihood estimators, and perform a score test to compare the zero-inflated quasi-binomial distribution with the zero-inflated binomial distribution, and the zero-inflated model with the homogeneous model (the model in which covariates are not considered). This analysis is illustrated with two data sets that are well known in the statistical literature and which contain a large number of zeros. 相似文献
265.
The utility of postcensal population estimates depends on the adequate measurement of four major components of demographic change: fertility, mortality, immigration, and emigration. Of the four components, emigration, especially of the foreign-born, has proved the most difficult to gauge. Without "direct" methods (i.e., methods identifying who emigrates and when), demographers have relied on indirect approaches, such as residual methods. Residual estimates, however are sensitive to inaccuracies in their constituent parts and are particularly ill-suited for measuring the emigration of recent arrivals. Here we introduce a new method for estimating foreign-born emigration that takes advantage of the sample design of the Current Population Survey (CPS): repeated interviews of persons in the same housing units over a period of 16 months. Individuals appearing in a first March Supplement to the CPS but not the next include those who died in the intervening year, those who moved within the country, and those who emigrated. We use statistical methods to estimate the proportion of emigrants among those not present in the follow-up interview. Our method produces emigration estimates that are comparable to those from residual methods in the case of longer-term residents (immigrants who arrived more than 10 years ago), but yields higher--and what appear to be more accurate--estimates for recent arrivals. Although somewhat constrained by sample size, we also generate estimates by age, sex, region of birth, and duration of residence in the United States. 相似文献
266.
Weiss MD 《Journal of homosexuality》2006,50(2-3):103-132
This article explores nonpractitioners' understandings of and responses to the increasingly mainstream representation of BDSM in U.S. media, focusing on the film Secretary (Shainberg, 2002). Survey, focus group, and interview data indicate that popular images of SM promote the acceptance and understanding of sexual minorities through two mechanisms: acceptance via normalization, and understanding via pathologizing. Rather than challenging the privileged status of normative sexuality, these mechanisms reinforce boundaries between protected/privileged and policed/pathological sexualities. Instead of celebrating increased representation, this article argues that political energy might be directed toward the desire that the popularity of BDSM representations signifies: the desire to encounter authentic, undisciplined, and noncommodified representations that would transgress the sexual norms of American postmodern consumer culture. 相似文献
267.
Graham S Gill A Lamers D 《Women and birth : journal of the Australian College of Midwives》2006,19(1):23-28
A very small proportion of newborns fail to establish a normal respiratory pattern without some assistance at birth and newborns requiring resuscitative measures at birth should have a skilled practitioner able to provide it. In this small hospital midwives felt unskilled in newborn resuscitation and paediatricians were not always immediately available. A stakeholder group gathered to discuss the problem. A training program was implemented that improved the skills, confidence and support of the attending midwife to resuscitate the newborn effectively. The aim was to improve the outcome for the infant whilst maintaining the mother's choice of birthing in a small local hospital close to family and friends. 相似文献
268.
In this article, we study how an expert system affects novice problem solving in a financial risk analysis domain. We demonstrate that novice performance is improved after exposure to an expert system. Further, we show that novice performance continues to improve when the system is withdrawn. By comparing learning curves for people with exposure to those without, we can assess how much the system has benefitted its users. We demonstrate a quantitative methodology to measure the increment of learning due to the use of an information technology. We also explore the issue of how expertise is transferred from the system to the user. 相似文献
269.
This study investigates the impact of worker learning, worker flexibility, and labor attrition on the system performance of a dual resource constrained (DRC) job-shop. The effects of learning and labor attrition have not been previously addressed in DRC literature. Results from the study, consistent with previous literature, show that the greatest benefits are achieved when inter-departmental worker flexibility is incrementally introduced into the system. In addition, the learning environment, which depends on the initial processing time of jobs and the learning rates of workers, is shown to impact the acquisition of flexibility. The study also shows that the impact of labor attrition on system performance under certain shop conditions may be significant. 相似文献
270.
Population Research and Policy Review - This paper examines the impact of school starting age on teenage marriage and motherhood in Vietnam. The investigation uses data from the 2009 Vietnam... 相似文献