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381.
382.
Kerr DC Capaldi DM Owen LD Wiesner M Pears KC 《Journal of marriage and the family》2011,73(5):1101-1116
Fatherhood can be a turning point in development and in men's crime and substance use trajectories. At-risk boys (N = 206) were assessed annually from ages 12 to 31 years. Crime, arrest, and tobacco, alcohol, and marijuana use trajectories were examined. Marriage was associated with lower levels of crime and less frequent substance use. Following the birth of a first biological child, men's crime trajectories showed slope decreases, and tobacco and alcohol use trajectories showed level decreases. The older men were when they became fathers, the greater the level decreases were in crime and alcohol use and the less the slope decreases were in tobacco and marijuana use. Patterns are consistent with theories of social control and social timetables. 相似文献
383.
At a data analysis exposition sponsored by the Section on Statistical Graphics of the ASA in 1988, 15 groups of statisticians analyzed the same data about salaries of major league baseball players. By examining what they did, what worked, and what failed, we can begin to learn about the relative strengths and weaknesses of different approaches to analyzing data. The data are rich in difficulties. They require reexpression, contain errors and outliers, and exhibit nonlinear relationships. They thus pose a realistic challenge to the variety of data analysis techniques used. The analysis groups chose a wide range of model-fitting methods, including regression, principal components, factor analysis, time series, and CART. We thus have an effective framework for comparing these approaches so that we can learn more about them. Our examination shows that approaches commonly identified with Exploratory Data Analysis are substantially more effective at revealing the underlying patterns in the data and at building parsimonious, understandable models that fit the data well. We also find that common data displays, when applied carefully, are often sufficient for even complex analyses such as this. 相似文献
384.
385.
David Perrier 《International Gambling Studies》2013,13(3):377-382
Social media has become an established tool to engage and maintain customer loyalty. However, its successful use involves a balance between promotion, public relations and corporate social responsibility. Nineteen individuals working in the Australian gambling industry were interviewed. The aim was to explore how gambling operators are using social media to engage with users and promote products, their considerations underpinning these actions, and the extent to which responsible gambling practices are included. All operators were active on social media and used these platforms to attempt to increase customer engagement and strengthen existing relationships. Gambling-related content was usually balanced against non-gambling content, or operators focused exclusively on non-gambling content. Sales goals or raising revenue were not direct aims of social media use. Operators sought to use social media as an indirect way to maintain their customer base and attract new customers via favourable ratings and information transfer. Few operators provided specific responsible gambling messages, despite being mindful of the dangers of targeting vulnerable populations, specifically young people and problem gamblers. This study is unique as it provides an in-depth first-hand account of how gambling operators are using social media. 相似文献
386.
Experiments in which very few units are measured many times sometimes present particular difficulties. Interest often centers on simple location shifts between two treatment groups, but appropriate modeling of the error distribution can be challenging. For example, normality may be difficult to verify, or a single transformation stabilizing variance or improving normality for all units and all measurements may not exist. We propose an analysis of two sample repeated measures data based on the permutation distribution of units. This provides a distribution free alternative to standard analyses. The analysis includes testing, estimation and confidence intervals. By assuming a certain structure in the location shift model, the dimension of the problem is reduced by analyzing linear combinations of the marginal statistics. Recently proposed algorithms for computation of two sample permutation distributions, require only a few seconds for experiments having as many as 100 units and any number of repeated measures. The test has high asymptotic efficiency and good power with respect to tests based on the normal distribution. Since the computational burden is minimal, approximation of the permutation distribution is unnecessary. 相似文献
387.
Although the urgency with which the Dutch East India Company administration at the Cape built defensive works was a direct result of their fear of attack from both land and sea, there was an additional imperative, for the Castle at Cape Town stood as a symbol of Dutch colonial aspirations. In this paper, we compare written and material texts of one part of the Castle's architecture to show firstly, how the discordances between such sources can reveal an underside of early colonization and secondly, how the Castle moat, in the seventeenth century a stamp of aspirant power, was by the mid‐nineteenth century a dump and a public nuisance. 相似文献
388.
This paper presents a problem structuring methodology to assess real option decisions in the face of unpredictability. Based on principles of robustness analysis and scenario planning, we demonstrate how decision-aiding can facilitate participation in projects setting and achieve effective decision making through the use of real options reasoning. We argue that robustness heuristics developed in earlier studies can be practical proxies for real options performance, hence indicators of efficient flexible planning. The developed framework also highlights how to integrate real options solutions in firms’ strategic plans and operating actions. The use of the methodology in a location decision application is provided for illustration. 相似文献
389.
390.
David Almeida Filipe Ribeiro Pedro M. Leunda Lorenzo Vilizzi Gordon H. Copp 《Risk analysis》2013,33(8):1404-1413
Risk assessments are crucial for identifying and mitigating impacts from biological invasions. The Fish Invasiveness Scoring Kit (FISK) is a risk identification (screening) tool for freshwater fishes consisting of two subject areas: biogeography/history and biology/ecology. According to the outcomes, species can be classified under particular risk categories. The aim of this study was to apply FISK to the Iberian Peninsula, a Mediterranean climate region highly important for freshwater fish conservation due to a high level of endemism. In total, 89 fish species were assessed by three independent assessors. Results from receiver operating characteristic analysis showed that FISK can discriminate reliably between noninvasive and invasive fishes for Iberia, with a threshold of 20.25, similar to those obtained in several regions around the world. Based on mean scores, no species was categorized as “low risk,” 50 species as “medium risk,” 17 as “moderately high risk,” 11 as “high risk,” and 11 as “very high risk.” The highest scoring species was goldfish Carassius auratus. Mean certainty in response was above the category “mostly certain,” ranging from tinfoil barb Barbonymus schwanenfeldii with the lowest certainty to eastern mosquitofish Gambusia holbrooki with the highest level. Pair‐wise comparison showed significant differences between one assessor and the other two on mean certainty, with these two assessors showing a high coincidence rate for the species categorization. Overall, the results suggest that FISK is a useful and viable tool for assessing risks posed by non‐native fish in the Iberian Peninsula and contributes to a “watch list” in this region. 相似文献