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991.
Taking out student loans to assist with the costs of postsecondary schooling in the US has become the norm in recent decades. The debt burden young adults acquire during the higher education process, however, is increasingly stratified with black young adults holding greater debt burden than whites. Using data from the NLSY 1997 cohort, we examine racial differences in student loan debt acquisition and parental net wealth as a predictor contributing to this growing divide. We have four main results. First, confirming prior research, black young adults have substantially more debt than their white counterparts. Second, we find that this difference is partially explained by differences in wealth, family background, postsecondary educational differences, and family contributions to college. Third, young adults’ net worth explain a portion of the black–white disparity in debt, suggesting that both differences in accumulation of debt and ability to repay debt in young adulthood explain racial disparities in debt. Fourth, the black–white disparity in debt is greatest at the highest levels of parents’ net worth. Our findings show that while social and economic experiences can help explain racial disparities in debt, the situation is more precarious for black youth, who are not protected by their parents’ wealth. This suggests that the increasing costs of higher education and corresponding rise in student loan debt are creating a new form of stratification for recent cohorts of young adults, and that student loan debt may be a new mechanism by which racial economic disparities are inherited across generations.  相似文献   
992.
In this paper, we investigate the use of the contribution to the sample mean plot (CSM plot) as a graphical tool for sensitivity analysis (SA) of computational models. We first provide an exact formula that links, for each uncertain model input Xj, the CSM plot Cj(·) with the first-order variance-based sensitivity index Sj. We then build a new estimate for Sj using polynomial regression of the CSM plot. This estimation procedure allows the computation of Sj from given data, without any SA-specific design of experiment. Numerical results show that this new Sj estimate is efficient for large sample sizes, but that at small sample sizes it does not compare well with other Sj estimation techniques based on given data, such as the effective algorithm for computing global sensitivity indices method or metamodel-based approaches.  相似文献   
993.
The Birnbaum–Saunders distribution is a positively skewed distribution that is frequently used for analyzing lifetime data. Regression analysis is widely used in this context when some covariates are involved in the life-test. In this article, we discuss the maximum likelihood estimation of the model parameters and associated inference. We discuss the likelihood-ratio tests for some hypotheses of interest as well as some interval estimation methods. A Monte Carlo simulation study is then carried out to examine the performance of the proposed estimators and the interval estimation methods. Finally, some numerical data analyses are done for illustrating all the inferential methods developed here.  相似文献   
994.
This study examined the dominant factors that predict the utilization of services by 129 identified elder abuse victims who reside in the community. Utilizing the Andersen Model, services accepted or rejected were analyzed from individual, family and environmental perspectives. Results indicated that service utilization is related to three "need" factors: (1) Victim has cognitive and ADL impairments, (2) Victim has poor health status (self rated), and (3) The abuser is financially dependent on the victim and is also the primary caregiver of the victim. "Enabling" factor (1) Victim lives alone. "Predisposing" factors (1) Abuser is substance abuser and (2) Abuser is female. A great proportion of the elder abuse victims in this study accepted services from an agency that provided a single entry point into the service system and had highly trained personnel utilizing a case management approach.  相似文献   
995.
This commentary discusses the decisions of child protective service (CPS) investigators to substantiate mothers for failure to- protect (FTP) in child sexual abuse cases. Four areas are identified in which the scientific literature remains inadequate to fully inform child maltreatment researchers, CPS practitioners and child welfare policymakers on models and outcomes for FTP substantiation decisions. Attention is called to the need for more information about how differences in statutory definitions, common guidelines, and professional education and training influence FTP substantiation decisions. Current gaps in the knowledge base on FTP and nonoffending caregivers are highlighted. doi:10.1300/J070v15n04_05.  相似文献   
996.
Background Most adults gamble recreationally yet few studies have systematically investigated for gender-related differences in recreational gamblers.Methods Logistic regression analyses were performed on data from a nationally representative sample of respondents from the 1998 Gambling Impact and Behavior Study. Results Female gamblers versus non-gamblers were more likely to report use of alcohol and drugs. Male gamblers versus non-gamblers were more likely to report alcohol use and abuse/dependence, any substance abuse/dependence, and lifetime incarceration. An analysis of gambling by gender group interaction effects did not identify significant differences in health-related measures. Male as compared with female gamblers reported beginning gambling earlier, experiencing higher past-year maximal losses and wins, and finding favorite and engaging in different types of gambling.Conclusions Despite heavier gambling in male as compared with female recreational gamblers, similar mental health functioning was observed in female and male past-year recreational gamblers. Types of gambling problematic for men and women are reflected in the gambling preferences of recreational gamblers.  相似文献   
997.
This work explores financial edgework by professional speculative traders as an explanation for the persistence of rogue trading in financial markets. The article joins in the scholarly application of “edgework,” the social psychological study of voluntary risk, to speculative trading. The discussion focuses on the origins and persistence of that subset of behavior wherein the trader knowingly creates the condition in which he or she endangers the brokerage house that employs them and even, at times, threatens the public's perception of the integrity of the securities industry. Going over the edge between risk taking and unauthorized rogue trading is explained by looking at five inducements to escalate risk taking provided in the securities industry. This examination of financial edgework demonstrates how and, to a lesser degree, why rogue trading is a result of the security industry's pursuit of and desire to capitalize upon yet not publicize an occupational culture stressing a “risk‐and‐win” ethos.  相似文献   
998.
Women are underrepresented in wilderness recreation despite the numerous benefits such activities provide to mental, physical, and emotional health. Several theories have been proposed linking women??s beliefs about their competence in outdoor spaces, fears of victimization, and concerns over retaining femininity to their lack of participation. We explore media representations of wilderness recreation as a possible agent in the gender socialization process that dissuades women from participation. Through analyzing advertisements from the 42 issues of Backpacker and Outside magazines published in 2008 and 2009 we find that, when women are shown, they are portrayed as having limited and passive roles in wilderness recreation. These advertisements also use the setting to reinforce traditional gender arrangements and paint women as consumers rather than conquerors of the wild. When women are shown as active participants in wilderness recreation, their physical accomplishments are often either downplayed or depicted as the endeavors of ??unique?? women who require feminization.  相似文献   
999.
1000.
In this paper, we derive explicit best linear unbiased estimators for one- and two-parameter exponential distributions when the available sample is multiply Type-II censored. Further, after noting that the maximum likelihood estimators do not exist explicitly, we propose some linear estimators by approximating the likelihood equations appropriately. Some illustrative examples from life-testing experiments are also presented.  相似文献   
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