1,388 research outputs found
In Which Schools Does Police Presence Most Exacerbate Racial Differentials in Arrest?
This study looks at racial disproportionalities in student arrests, particularly with school police presence. This study extends Homer and Fisher’s (2020) work, which finds higher arrest rates and stronger effects of police presence for Black than White students across schools, by investigating school racial compositions and context factors that are associated with the strongest relationships between police presence and higher arrest rates of Black than White students. Results show the largest within-school arrest rate differences between Black and White students in high schools with officers and that schools with lower Black student enrollment percentages show larger Black-White student arrest gaps
Large NaCl-effect on the Decomposition Rate of Chlorate Ions in HCl-containing Brine Solutions and Its Consequences for the Chlor-alkali Industry
The decomposition rate of chlorate (NaClO3) in aqueous solutions (brines) containing initially 6:1 mol/mol HCl:NaClO3 is studied at 90°C at various NaCl contents experimentally. A strong positive effect of NaCl addition is shown on the decomposition rate of chlorate. It is found more reasonable in the chlor-alkali industry first to saturate the brine by sodium chloride and only then to eliminate from it the chlorate by adding HCl (before the solution is transferred into the electrolysis cell to be protected from the chlorate ions)
Head Start at Ages 3 and 4 Versus Head Start Followed by State Pre-K: Which Is More Effective?
As policy-makers contemplate expanding preschool opportunities for low-income children, one possibility is to fund two, rather than one year of Head Start for children at ages 3 and 4. Another option is to offer one year of Head Start followed by one year of pre-k. We ask which of these options is more effective. We use data from the Oklahoma pre-k study to examine these two ‘pathways’ into kindergarten using regression discontinuity to estimate the effects of each age-4 program, and propensity score weighting to address selection. We find that children attending Head Start at age 3 develop stronger pre-reading skills in a high quality pre-kindergarten at age 4 compared with attending Head Start at age 4. Pre-k and Head Start were not differentially linked to improvements in children’s pre-writing skills or pre-math skills. This suggests that some impacts of early learning programs may be related to the sequencing of learning experiences to more academic programming
Factors Predictive of Being Bullies or Victims of Bullies in US Elementary Schools.
We analyzed a population-representative cohort (N=13,611; Mage at kindergarten, first, and second grade = 67.5, 79.5, and 91.5 months, respectively) to identify kindergarten to second grade factors predictive of being bullies or victims during third to fifth grade. We did so by estimating a block recursive structural equation model (SEM) with three sets of predictors. These were: (a) individual and school socio-demographics; (b) family distress and harsh parenting; and (c) individual behavior and achievement. Relations between each of the included variables and the bullying outcomes were simultaneously estimated within the SEM. Thus, each variable served as a control for estimating the effects of the other variables. We used robust standard errors to account for student clustering within schools. Results indicated that externalizing problem behavior strongly predicted being a bully ([ES] = .56, p\u3c.001) and a victim (ES=.29, p\u3c.001). We observed a negative relation between being Hispanic and being a victim (ES = −.10, p\u3c.001) and a positive relation between being Black and being a bully (ES = .11, p\u3c.001). We also observed statistically significant relations between a family’s socioeconomic status and being a bully (ES = −.08, p\u3c.001) as well as school poverty and being a victim (ES = .07, p\u3c.001). The results advance the field’s limited understanding of risk and protective factors for bullying perpetration or victimization during elementary school and provide additional empirical support for assisting young children already exhibiting externalizing problem behaviors
Which Children are Frequently Victimized in U.S. Elementary Schools? Population-based Estimates
We analyzed a population-based cohort of 11,780 U.S. kindergarten children to identify risk and protective factors predictive of frequent verbal, social, reputational, and/or physical bullying victimization during the upper elementary grades. We also stratified the analyses by biological sex. Both girls and boys displaying kindergarten externalizing problem behaviors were at consistently higher risk of frequent victimization during 3rd-5th grade (for the combined sample of boys and girls, verbal odds ratio [OR] = 1.82, social OR = 1.60, reputational OR = 1.85, physical OR = 1.67, total OR = 1.93). Hispanic children relative to non-Hispanic White children and those from higher income families were the most strongly and consistently protected from victimization. Boys were more likely to be physically bullied but less likely to be verbally, socially or reputationally bullied than girls. Other variables including disability, cognitively stimulating parenting, academic achievement, and internalizing behavior problems had statistically significant but less consistent and generally weaker relations with frequent victimization
Battery Study for the Shuttle Orbiter EAPU Upgrade
The use of Electric Auxiliary Power Unit (EAPU) in commercial, and military aviation, and in commercial electric automobiles, is reviewed. The specifications of the battery to be used in the space shuttle are reviewed, and the possible vendors discussed. The testing activity and the reliability and the safety features are presented
The Subcomponents of Affect Scale (SAS): Validating a Widely Used Affect Scale
Objective
There is a need for a brief affect scale that also encompasses different components of affect relevant for researchers interested in physiological and health outcomes. The Subcomponents of Affect Scale (SAS) meets this need. This 18-item scale has nine positive and nine negative affect items encompassing six subscales (calm, well-being, vigour, depression, anxiety, anger). Previous research using the SAS has demonstrated its predictive validity, but no work has tested its subscale structure or longitudinal validity. Design
Data from the Common Cold Project in which individuals (N = 610) completed the SAS over the course of seven days were used. Results
Confirmatory factor analysis demonstrated the reliability of the subscale structure of the SAS across seven days (positive affect subscale structure: CFIs ≥ 0.98; negative affect subscale structure: CFIs ≥ 0.94 with day 6 CFI = 0.91) and tests of factorial invariance showed the scale is valid to use over time. Conclusions
These results confirm the psychometric validity of the subscale structure of the SAS and imply that the subscales can be used longitudinally, allowing for its use in health research as well as non-health research that can benefit from its subscale structure and longitudinal capabilities
Preschool center care quality effects on academic achievement: An instrumental variables analysis.
Much of child care research has focused on the effects of the quality of care in early childhood settings on children's school readiness skills. Although researchers increased the statistical rigor of their approaches over the past 15 years, researchers' ability to draw causal inferences has been limited because the studies are based on nonexperimental designs. The purpose of the present study was to demonstrate how an instrumental variables approach can be used to estimate causal impacts of preschool center care quality on children's academic achievement when applied to a study in which preschool curricula were randomly assigned across multiple sites. We used data from the Preschool Curriculum Evaluation Research Initiative (PCER; n = 2,700), in which classrooms or preschools were randomly assigned to that grantee's treatment curriculum or "business as usual" conditions in 18 research sites. Using this method, we demonstrate how developmental researchers can exploit the random-assignment designs of multisite studies to investigate characteristics of programs, such as preschool center care quality, that cannot be randomly assigned and their impacts on children's development. We found that the quality of preschool care received by children has significant, albeit modest, effects on children's academic school readiness, with effect sizes of .03 to .14 standard deviation increases in academic achievement associated with a 1 standard deviation increase in quality. Applications and potential policy implications of this method are discussed
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