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We propose kernel density estimators based on prebinned data. We use generalized binning schemes based on the quantiles points of a certain auxiliary distribution function. Therein the uniform distribution corresponds to usual binning. The statistical accuracy of the resulting kernel estimators is studied, i.e. we derive mean squared error results for the closeness of these estimators to both the true function and the kernel estimator based on the original data set. Our results show the influence of the choice of the auxiliary density on the binned kernel estimators and they reveal that non-uniform binning can be worthwhile.  相似文献   
24.
Abstract

Genital herpes virus infection is an important target for health education efforts because of its apparently rising incidence in the college student population and because it can have potentially serious psychological as well as medical consequences. In order to better understand the health education and counseling needs of students, the present study surveyed knowledge and attitudes about genital herpes of 190 university students using a gynecology clinic and of 161 students using a general medical clinic. The students were found to have a high degree of familiarity with the disease, its cause, and mode of transmission, but tended to view the consequences of the disease as more severe than is actually warranted by the common medical complications. There was some degree of misinformation about prevention and treatment of the disease and some negative attitudes about patients suffering from it, but the survey respondents endorsed a high level of responsible behavior with regard to the disease and expressed some optimism about the possibility of adapting to it. These findings suggest specific misconceptions about genital herpes that might be amenable to a mass education approach. They also suggest the need for a counseling program that centers around reasonable reassurance and appropriately positive psychological and medical management for newly diagnosed patients.  相似文献   
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The relative performance of a component of a series system in two different environments is considered. The conditional probability of the failure of the system due to the failure of the specified component given that the system failed before time t is regarded as a measure of relative importance of the component to the system. A U-statistic test for checking the equality of the relative importance of the component to the system in two different environments against the alternative that the relative importance is smaller in one of the environments, is proposed. Some simulation results for estimating the power of the test are reported. The proposed test is applied to one real data set and it is seen that a different aspect of the data is brought out by this comparison than that by the comparisons of the absolute importance functions such as the subsurvival functions, considered in earlier studies.  相似文献   
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Hypothesized risk factors for men's and women's clinically significant intimate partner violence (CS‐IPV) from four ecological levels (i.e., individual, family, workplace, community) were tested in a representative sample of active‐duty U.S. Air Force members (N = 42,744). When considered together, we expected only individual and family factors to account for unique variance in CS‐IPV perpetration. Hypothesized factors from all four ecological levels were related to men's CS‐IPV perpetration bivariately, but, as expected, only individual and family factors accounted for unique variance across ecological levels. For women, only risk factors from the individual and family levels were significantly related to CS‐IPV perpetration even bivariately. Results imply somewhat different risk profiles across gender and identify ecological risk factors of men's CS‐IPV not previously studied.  相似文献   
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I interviewed 57 low-income fathers about how they define responsible fatherhood. Unlike findings from previous research, their definition did not include financial provision or daily caregiving. Instead, their definition included six dimensions, some of which resemble a “Big Brother”: spending time in non-caregiving activities; avoiding harm by voluntarily distancing from the child when it is in the child’s best interest; acknowledging paternity in non-legal forums; spending money on gifts, joint activities, and special needs; monitoring the child’s home for trouble; and minimizing absences in the child’s life. Because these fathers do not emphasize traditional breadwinning or primary caregiving, their responsible fathering beliefs and behavior may be unappreciated by academics, practitioners, and policy makers.  相似文献   
28.
Market failures, government failures and some of the characteristics of both the poor and business actors as well as their environment can act as barriers preventing the poor from participating more actively in markets, both as consumers and as producers. Private actors ‐ including for‐profit and not‐for‐profit entities, often in partnership with the public sector ‐ have been able to mitigate some of these constraints through innovations that have helped to make markets more inclusive for the poor, enabling them not just to gain access, but also to participate in ways that enhance their economic empowerment and human development. This article identifies the strategies and innovations used and devises a possible typology for them.  相似文献   
29.
采用双三次NURBS方法对某型号转子进行几何造型,对造型过程中出现的曲面延伸、求交和裁剪等问题进行了研究.根据叶片的形状特征,以曲线的几何形式为基础,提出了一种简单实用的曲线曲面延伸方法,实现了切矢量连续的叶片型面的延伸.对于两相交面分别为自由曲面和解析曲面的求交问题,提出了一种简化的跟踪算法,实现了转子叶片型面和圆台面的准确求交和裁剪,从而实现转子精确的几何造型.  相似文献   
30.
为了解决维修间隔期确定的难题,建立了维修间隔期和总停机时间之间关系的目标函数,以及时间延迟维修模型.根据故障记录数据和预防维修活动的检查数据,采用最大似然法估计有关缺陷发生率和时间延迟分布等参数.在所建立目标函数和估计参数的基础上,计算出最优的维修间隔期.  相似文献   
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