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981.
Using data from 7272 adolescent US girls, we explore how girls’ race/ethnic group status affects their bodyweight, perceptions of overweight, and weight control practices. We hypothesize that a girl’s race/ethnic status influences her basic identity which in turn prompts her to adopt or reject a “drive for thinness.” After controlling for family and peer support, school engagement, family SES, maturation, and family structure, we find that girls’ race/ethnic status influences their susceptibility to the thinness ideals of mainstream culture. African American girls weigh more than Asian, Hispanic, or White girls, but at any given weight they perceive themselves as overweight and attempt to control their weight less. Asian American and White girls invest most in thinness dynamics. Some evidence also suggests girls from lower SES families are less driven to be thin. Our results affirm the utility of viewing material bodies as “situations” that are experienced and interpreted in accord with identity group relations and dynamics. 相似文献
982.
983.
We examine differences in the value of statistical life (VSL) across potential wage levels in panel data using quantile regressions
with intercept heterogeneity. Latent heterogeneity is econometrically important and affects the estimated VSL. Our findings
indicate that a reasonable average cost per expected life saved cut-off for health and safety regulations is 7 million to7 million to
8 million per life saved, but the VSL varies considerably across the labor force. Our results reconcile the previous discrepancies
between hedonic VSL estimates and the values implied by theories linked to the coefficient of relative risk aversion. Because the VSL varies elastically with income, regulatory agencies should regularly update the VSL used in benefit assessments,
increasing the VSL proportionally with changes in income over time. 相似文献
984.
There has been considerable interest in studying the magnitude and type of inheritance of specific diseases. This is typically derived from family or twin studies, where the basic idea is to compare the correlation for different pairs that share different amount of genes. We here consider data from the Danish twin registry and discuss how to define heritability for cancer occurrence. The key point is that this should be done taking censoring as well as competing risks due to e.g. death into account. We describe the dependence between twins on the probability scale and show that various models can be used to achieve sensible estimates of the dependence within monozygotic and dizygotic twin pairs that may vary over time. These dependence measures can subsequently be decomposed into a genetic and environmental component using random effects models. We here present several novel models that in essence describe the association in terms of the concordance probability, i.e., the probability that both twins experience the event, in the competing risks setting. We also discuss how to deal with the left truncation present in the Nordic twin registries, due to sampling only of twin pairs where both twins are alive at the initiation of the registries. 相似文献
985.
Preventing unsuitable people from working with children—the criminal justice and court services bill
Terry Thomas 《Child Abuse Review》2001,10(1):60-69
The continuing concern to safeguard children from abuse in schools, children's homes and similar settings has led to proposals to make it an offence for those with convictions against children to even apply for work with children. The Criminal Justice and Court Services Bill will introduce ‘disqualification orders’ for such offenders. The background development of this Bill is considered, together with the way the new orders will fit with existing criminal record check arrangements, current bans and the role of the forthcoming Criminal Records Bureau, which will tie all these systems together in a ‘one‐stop shop’. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
986.
The data set of 2,182 gay/bisexual men's month‐long sexual diaries collected by the United Kingdom Socio‐sexual Investigations of Gay Men and Aids (Project SIGMA) was used to analyse the extent to which acts of anal intercourse (AI) are distributed among gay men, using the Lorenz/Gini methodology for measuring concentration. Most individuals (60%) who engage in AI do so only once or twice a month, but there is a long tail of those who do it much more. In terms of the amount of AI acts, one tenth of the individuals are performing half of the acts of AI. The Gini coefficient of concentration is high (0.55). Factors most affecting rates and concentration of risk behaviour include relationship status, HIV sero‐status and concordant/discordant partner status. 相似文献
987.
This article investigates the comprehensive effects of unemployment insurance (UI) policies on the amount of time and unemployment that individuals report between jobs. The econometric model jointly determines the effects of UI on the lengths of nonemployment spells, the classification of these spells as unemployment, and the likelihood of collecting program benefits. The model carefully attempts to isolate variation in UI benefits attributable to differences in generosity across programs to avoid biases in estimating policy effects induced by other contaminating sources of benefit variation. Using data on men from the National Longitudinal Survey of Youth, the empirical results find (a) UI recipients typically experience longer spells between jobs, at least up to the exhaustion of UI benefits, and report substantially larger fractions of these spells as unemployment; (b) weekly benefit amounts exert no significant influence on the likelihood of UI recipiency, on the length of spells between jobs, or on the fraction of these spells classified as unemployment; and (c) increases in weeks of UI eligibility raise the likelihood of UI collection and lengthen the number of weeks of unemployment between jobs by inducing long spells to become longer and not by altering short-duration behavior. 相似文献
988.
In many circumstances it is necessary to design an experiment with partial confounding of parameter estimates. In this situation, one would like to have tools to assess and compare candidate designs graphically. In this paper we discuss two graphical representations of design properties, and illustrate their application with two examples. 相似文献
989.
Connie Crihfield R.N. 《Journal of American college health : J of ACH》2013,61(2):103-104
The results of several studies have established the validity of the SCOFF questionnaire (a 5-question screening tool for eating disorders), but researchers need to explore further replicability using the US version in the graduate school population. In this study, the authors asked 335 graduate students attending the Northwestern student health clinic on the Chicago campus to complete a written survey anonymously. A total of 305 (91%) patients completed the survey. The sensitivity and specificity for the SCOFF was 53.3% and 93.2%, respectively. This produced a PPV (the proportion who tested positive on the screen and actually had an eating disorder) of 66.7% and an NPV (the proportion of those who tested negative on the screen and actually did not have an eating disorder) of 88.7%. More than 80% of respondents were dissatisfied with their shape and weight, with over one third having a moderate to severe body image disturbance. The SCOFF is an easy instrument to administer that health care providers can use to screen for eating disorders in the primary care setting. 相似文献
990.
A longitudinal analysis of family migration and the gender gap in earnings in the united states and great britain 总被引:2,自引:0,他引:2
This article uses longitudinal data for the United States and Great Britain to examine the impact of residential mobility
and childbirth on the earnings of women, their family earnings, and the related division of earnings by gender. This project
is the _ rst to compare explicitly the impact of childbirth and family migration on women’s earnings, and it extends prior
cross-sectional and longitudinal studies on isolated countries by providing a direct contrast between two major industrialized
nations, using comparable measures. The results indicate that families respond in similar ways in both countries to migration
and childbirth. In response to both migration and childbirth, women’s earnings fall at the time of the event and recover slowly
afterward, but the magnitude of the impact is roughly twice as large for childbirth as for migration. However, migration but
not the birth of a child is also associated with a significant increase in total family earnings because of increased husbands’
earnings. As a result, the effect of migration on the relative earnings of wives to husbands is similar to the effect of childbirth.
These results suggest that family migration should be given consideration in the literature on the gender earnings gap. 相似文献