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In 2008, the federal government allotted $7 billion in child care subsidies to low-income families through the state-administered Child Care and Development Fund (CCDF), now the government's largest child care program (US DHHS, 2008). Although subsidies reduce costs for families and facilitate parental employment, it is unclear how they impact the quality of care families purchase. This study investigates the impact of government subsidization on parents’ selection of child care quality using multivariate regression and propensity score matching approaches to account for differential selection into subsidy receipt and care arrangements. Data were drawn from the Child Care Supplement to the Fragile Families and Child Wellbeing Study (CCS-FFCWS), conducted in 2002 and 2003 in 14 of the 20 FFCWS cities when focal children were 3 years old (N = 456). Our results indicate that families who used subsidies chose higher quality care than comparable mothers who did not use subsidies, but only because subsidy recipients were more likely to use center-based care. Subgroup analyses revealed that families using subsidies purchased higher-quality home-based care but lower-quality center-based care than comparable non-recipients. Findings suggest that child care subsidies may serve as more than a work support for low-income families by enhancing the quality of nonmaternal care children experience but that this effect is largely attributable to recipients’ using formal child care arrangements (versus kith and kin care) more often than non-recipients.  相似文献   
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While numerous studies attest to a relationship between academic self-concept and achievement, a variety of measures of self-concept have been used, and the equivalence of these instruments has received limited attention. In this investigation, the Self-Concept of Ability Scale (SCAS) and the newer and less examined Self-Perception of Attainment Scale (SPAS) were compared for their ability to predict achievement in reading as measured by the California Achievement Test (CAT). We predicted that: (a) both scales would be significant predictors of reading achievement, (b) when used as single predictors, the SCAS would have significantly greater weight than the SPAS, and (c) a linear combination of these scales would have greater weight than either scale alone. Using 187 eighth-grade students, we confirmed that both scales were significant predictors of achievement in reading and that a linear combination of the two accounted for more variance than either scale alone. We did not find, however, that the SCAS was a significantly better predictor than the SPAS.  相似文献   
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The purpose of this study was to determine the validity of 23 anthropometric equations for estimating body composition and minimal wrestling weight in high school wrestlers. A total of 409 high school wrestlers (M age +/- SD = 16.42 +/- 1.03 yrs) volunteered for this study. Twenty-three anthropometric measures including eight skinfolds, nine circumferences, and six diameters were obtained from each subject. The mean body density, determined from underwater weighing, was 1.0748 +/- 0.0100 g.cm-3. The crossvalidation analyses indicated that the quadratic skinfold equation of Lohman resulted in the most accurate estimation of body density. The total error, constant error, standard error of estimate, and r for this equation were 0.0077 g.cm-3, -0.0003 g.cm-3, 0.0076 g.cm-3 and .65, respectively. Furthermore, the results of this investigation indicated that the minimal wrestling weight equations of Tcheng and Tipton resulted in total error values (5.54 to 6.06 kg) which were too large to be of practical use for high school wrestlers.  相似文献   
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