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21.
Objective: To examine the psychometric properties of a measure of cannabis-specific Protective Behavioral Strategies (PBS), which assesses ways in which students may reduce cannabis-related risk. Participants: Respondents to the American College Health Association – National College Health Assessment II (N = 580) during Spring 2015. Methods: Exploratory Factor Analysis (EFA) and Exploratory Structural Equation Modeling (ESEM) were used to identify and replicate the factor structure of the measure. Results: Results support a four-factor model (Respiratory Health, Frequency/Quantity, Socializing, and General Health) with close approximate fit (Χ2 (310) = 565.96, p < .001, RMSEA = .038 (.033, .043; 90% CI), CFI = .961, TLI = .929, SRMR = .033). Support for the convergent validity and construct validity of the measure was also found. Conclusions: This is the initial step in the development of a standard, psychometrically validated measure of cannabis PBS that has the potential to inform future research and interventions.  相似文献   
22.
Regression-based studies of inequality model only between-group differences, yet often these differences are far exceeded by residual inequality. Residual inequality is usually attributed to measurement error or the influence of unobserved characteristics. We present a model, called  variance function regression , that includes covariates for both the mean and variance of a dependent variable. In this model, the residual variance is treated as a target for analysis. In analyses of inequality, the residual variance might be interpreted as measuring risk or insecurity. Variance function regressions are illustrated in an analysis of panel data on earnings among released prisoners in the National Longitudinal Survey of Youth. We extend the model to a decomposition analysis, relating the change in inequality to compositional changes in the population and changes in coefficients for the mean and variance. The decomposition is applied to the trend in U.S. earnings inequality among male workers, 1970 to 2005.  相似文献   
23.
Objective: The ways that college students cope with stress, particularly interpersonal stress, may be a critical factor in determining which students are at risk for impairing mental health disorders. Using a control-based model of coping, the present study examined associations between interpersonal stress, coping strategies, and symptoms. Participants: A total of 135 undergraduate students from 2 universities. Methods: Interpersonal stress, coping strategies, depression, anxiety, and somatization were assessed via self-report. Results: Students reporting more interpersonal stress reported more depression, anxiety, and somatization, and they reported less use of engagement coping strategies and greater use of disengagement coping strategies. Engagement coping strategies accounted for a significant portion of the association between interpersonal stress and mental health symptoms. Unexpectedly, coping strategies did not moderate the association between stress and mental health symptoms. Conclusion: Interventions designed to improve students' coping strategies may be an effective way to reduce mental health problems on college campuses.  相似文献   
24.
Disproportionality in special education includes the underrepresentation and overrepresentation of children by gender, economic status, race, ethnicity, language, and culture. This article reviews literature on disproportionality in the United States, Germany, Kenya, and India. Societal views of disability, classism, racism, and inequitable assessment are among the factors that contribute to disproportionality. Preventative medicine, equitable access to resources, ethical and effective assessment procedures, and educational practices that are gender equitable and culturally responsive may reduce the problem of disproportionality.  相似文献   
25.
A three-level growth-curve model was applied to estimate perceived impact growth trajectories, using multi-year data from project and school surveys on outcome and program implementation collected from 59 sites and approximately 1165 participating schools in the Safe Schools and Healthy Students Initiative. Primary interest is to determine whether and how project-level and school-level correlates affect schools’ perceptions of the Initiative's effectiveness over time when the effects of the pre-grant environmental conditions, grant operations, and near-term outcomes are considered. Coordination and service integration, comprehensive programs and activities for early childhood development, and change in school involvement were found to be significant predictors of school-perceived overall impact when the effect of poverty was considered. Partnership functioning, perceived importance of school resources, and school involvement were found to be significant predictors of school-perceived impact on substance use prevention when the effect of poverty was considered.  相似文献   
26.
The inclusion of technology in the classroom is an increasingly important feature of effective instruction. The implementation of Common Core Standards in many states also requires teachers to consider new pedagogical strategies to support meaningful learning. This article explores the intersection between technology demands and curricular change by examining apps that can be used to support Common Core State Standards instruction in history/social studies. Specifically, the authors highlight several apps that they presented at a professional development workshop for six to twelve history/social studies teachers and discuss the teachers' feedback regarding the strengths and limitations of apps to support their instruction. Conclusions are drawn and recommendations for history/social studies teachers using apps in the classroom are provided.  相似文献   
27.
Lead is a recognized neurotoxicant, but estimating effects at the lowest measurable levels is difficult. An international pooled analysis of data from seven cohort studies reported an inverse and supra‐linear relationship between blood lead concentrations and IQ scores in children. The lack of a clear threshold presents a challenge to the identification of an acceptable level of exposure. The benchmark dose (BMD) is defined as the dose that leads to a specific known loss. As an alternative to elusive thresholds, the BMD is being used increasingly by regulatory authorities. Using the pooled data, this article presents BMD results and applies different statistical techniques in the analysis of multistudy data. The calculations showed only a limited variation between studies in the steepness of the dose‐response functions. BMD results were quite robust to modeling assumptions with the best fitting models yielding lower confidence limits (BMDLs) of about 0.1–1.0 μ g/dL for the dose leading to a loss of one IQ point. We conclude that current allowable blood lead concentrations need to be lowered and further prevention efforts are needed to protect children from lead toxicity.  相似文献   
28.
Because of their nice properties relative to the frequency of occurrence of n-tuples, Tausworthe sequences have been used frequently in recent years as the basis for random number generators. This paper describes a similar result relative to the frequency of occurrence of maximal-length strings of like bits. In particular, for any full-period Tausworthe sequence, the distribution of string lengths is precisely equal to the expected distribution of string lengths for a truly random bit sequence of comparable size.  相似文献   
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30.
Set-point theory is the main research paradigm in the field of subjective well-being (SWB). It has been extended and refined for 30 years to take in new results. The central plank of the theory is that adult set-points do not change, except temporarily in the face of major life events. There was always some ‘discordant data’, including evidence that some events are so tragic (e.g. the death of one’s child) that people never regain their set-point. It was possible to dismiss these events as ‘exceptions’ and maintain the theory. However, several new findings are emerging, which cannot be dismissed as ‘exceptions’ and which appear to require substantial revisions or replacement of set-point theory. Many of these findings are based on the German Socio-Economic Panel Survey (SOEP 1984-), which provides the longest available time series on life satisfaction. Despite its centrality, the concept of the set-point is often not precisely defined. In this paper three alternative working definitions are offered. Depending on which definition is used, it is found that over 20 years 14–30% of German panel members recorded large and apparently permanent changes in their set-points. Changes of this magnitude are not compatible with set-point theory as currently understood. The challenge for SWB researchers now is to develop a theory which can account for change as well as stability.  相似文献   
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