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101.
In nonregular problems where the conventional \(n\) out of \(n\) bootstrap is inconsistent, the \(m\) out of \(n\) bootstrap provides a useful remedy to restore consistency. Conventionally, optimal choice of the bootstrap sample size \(m\) is taken to be the minimiser of a frequentist error measure, estimation of which has posed a major difficulty hindering practical application of the \(m\) out of \(n\) bootstrap method. Relatively little attention has been paid to a stronger, stochastic, version of the optimal bootstrap sample size, defined as the minimiser of an error measure calculated directly from the observed sample. Motivated by this stronger notion of optimality, we develop procedures for calculating the stochastically optimal value of \(m\). Our procedures are shown to work under special forms of Edgeworth-type expansions which are typically satisfied by statistics of the shrinkage type. Theoretical and empirical properties of our methods are illustrated with three examples, namely the James–Stein estimator, the ridge regression estimator and the post-model-selection regression estimator.  相似文献   
102.
This article describes several features included in a CaliforniaHealth Interview Survey cell phone pilot study that differ fromearlier cell phone surveys conducted in the United States. Onedifference is that the study used a screening design and onlyadults living in cell-only households were interviewed. Mostof the previous studies used dual frame designs. Another differencewas the development and implementation of a within-householdadult sampling procedure to cover adults when cell phones wereshared in the household. The study was also intended to determineif conducting a cell phone interview of the same scope and lengthas a regular telephone interview was feasible. Most previoussurveys were focused on cell phone topics and were shorter thanthe comparable landline surveys. We then explore some interestingproblems that arise in weighting a cell phone survey using ascreening design. We conclude with a discussion of planninga new cell phone survey in 2007 that incorporates findings fromthis study.  相似文献   
103.
Two studies examined the relationships among injunctive norms and college student gambling. In study 1 we evaluated the accuracy of perceptions of other students’ approval of gambling and the relationship between perceived approval and gambling behavior. In study 2 we evaluated gambling behavior as a function of perceptions of approval of other students, friends, and family. In study 1, which included 2524 college students, perceptions of other students’ approval of gambling were found to be overestimated and were negatively associated with gambling behavior. The results of study 2, which included 565 college students, replicated the findings of study 1 and revealed positive associations between gambling behavior and perceived approval of friends and family. Results highlight the complexity of injunctive norms and the importance of considering the reference group (e.g., peers, friends, family members) in their evaluation. Results also encourage caution in considering the incorporation of injunctive norms in prevention and intervention approaches.  相似文献   
104.
105.
OBJECTIVE: Maryland became the first state to pass a vaccination law requiring college and university students living on campus to obtain a meningococcal vaccination or to sign a waiver refusing vaccination because college students are at increased risk for disease. The authors sought to identify how Maryland colleges addressed the law and determine whether schools were in full compliance. PARTICIPANTS: The authors surveyed 32 college/university administrators via a self-administered questionnaire. METHODS: The authors calculated vaccination and waiver rates and assessed compliance with the law overall and with specific law components. RESULTS: Among 28 participating schools, annual vaccination rates and waiver rates among students during 2000-2004 ranged from 66%-76% and 12%-17%, respectively. Two (7%) schools were compliant with all components of the law. CONCLUSIONS: Mandatory vaccination laws do not ensure compliance at the college and university level. Mandatory reporting, increased education, and collaboration between colleges and universities and public health agencies are needed.  相似文献   
106.
Financial Issues Associated with Having a Child with Autism   总被引:2,自引:2,他引:0  
Data from the Family Experiences with Autism Survey are used to identify factors associated with financial problems in families that have a child with autism. Likelihood of financial problems was positively associated with use of medical interventions, having unreimbursed medical or therapy expenses, and having relatively lower income. Use of speech and language therapy was negatively associated with likelihood of financial problems. Many survey respondents forfeited future financial security and even experienced bankruptcy to provide needed therapy for a child with autism. Specific ways that financial advisors can help families that have a child with autism are outlined.
Dana Lee BakerEmail:
  相似文献   
107.
While the relationships between health insurance and the labor supply of women have been explored in the literature, little is known about the effects of offering public health insurance on the labor supply decisions of married women. This paper examines how the enactment of the State Children’s Health Insurance Program (SCHIP) affected the labor supply decisions of married women. Our empirical analysis showed that certain groups of married women reduced their number of hours worked upon SCHIP implementation. The results imply it is possible that some wives decreased their labor supply in order to make their children eligible for public health insurance.
Ho Jin LeeEmail:
  相似文献   
108.
Is Work-Family Policy Use Related to the Gendered Division of Housework?   总被引:6,自引:6,他引:0  
Researchers have proposed that work-family policy use may either reinforce or challenge the existing gendered division of labor within couples, but results from prior studies have been inconclusive. Using data from a regional survey of work and family life, we extend this research by focusing on how housework is divided within couples and by differentiating between traditionally female- and male- typed housework tasks. Results show that among dual-earning women, policy use is not related to share of female- or male-typed tasks. Among dual-earning men, policy use is positively related to share of female-typed tasks and negatively related to share of male-typed tasks. These findings suggest that work-family policy use does not reinforce the gendered division of housework.
Mary C. NoonanEmail:
  相似文献   
109.
The overall aim of the two school-based pilot studies was to evaluate whether an approach to prevention that focused on changing child impulse control, decision making, and social competence can be effective in changing attitudes toward food intake and physical activity as risk factors for obesity. The strategy used was to translate specific components of one evidence-based program for violence prevention (Promoting Alternative Thinking Strategies: PATHS) into an elementary school curriculum program for obesity prevention. Both studies demonstrated significant changes in positive attitudes toward self-regulation of appetitive behavior. In addition, Study 2 demonstrated positive changes in actual food choices and television viewing patterns. Implications are that comprehensive efforts to prevent youth risk for obesity should include as one component school-based curricula that target self-regulation and decision-making skills.  相似文献   
110.
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