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51.
Regression analysis aims to estimate the approximate relationship between the response variable and the explanatory variables. This can be done using classical methods such as ordinary least squares. Unfortunately, these methods are very sensitive to anomalous points, often called outliers, in the data set. The main contribution of this article is to propose a new version of the Generalized M-estimator that provides good resistance against vertical outliers and bad leverage points. The advantage of this method over the existing methods is that it does not minimize the weight of the good leverage points, and this increases the efficiency of this estimator. To achieve this goal, the fixed parameters support vector regression technique is used to identify and minimize the weight of outliers and bad leverage points. The effectiveness of the proposed estimator is investigated using real and simulated data sets.  相似文献   
52.
管理信息系统故障影响着企业信息工程的开展。及时识别故障,能够为企业争取更多时间处理故障。因此,管理信息系统故障识别有着重要的研究意义和实践意义。基于支持向量机,构建管理信息系统故障识别模型,通过把样本应用于该模型,结果表明该模型具有较好的准确性,能有效识别管理信息系统故障。  相似文献   
53.
This article seeks to demonstrate and analyze the cultural and emotional work surrogate mothers collectively engage in on the largest surrogacy support website, http://www.surromomsonline.com . Surrogate mothers’ online stories and discussions frame contract surrogacy as a “labor of love.” Women often describe their surrogacy as a “journey” of shared love; they hope for a lasting relationship with the couple they carry for. This article explores how the language of love, learned and internalized through online communication with other surrogates, creates both a cultural conceptualization of surrogacy and a ground for action. Love and altruistic giving are consistent with close interpersonal rather than market relationships; surrogates hope for a long‐term friendship with their couple. Surrogacy journeys, however, not infrequently end in disappointment; surrogates feel betrayed when couples cut ties. As a result of collective learning, surrogates’ discussions increasingly articulate the position that love, even when unreciprocated, can lead to repeated giving; love is noble and ennobling. Surrogates find appreciation and support in their online surrogacy community where they agree that giving life is a moral good. This stance has contributed to a renewed enthusiasm to bear children for others.  相似文献   
54.
The current study used dyadic data to investigate the impact of relationship type and social support on the retrospective accounts of commitment trajectories of romantic relationships. Past research suggests that social support is a positive contributor to relationship stability and commitment, which may be especially true for partners in interracial relationships who face broader societal opposition than intraracial couples. Using multilevel modeling, we investigated the effects of sex, relationship type, and social support on reports of commitment. Results showed differences in trajectories of commitment based on couple type (interracial vs. intraracial) for both men and women. Social support was found to have an especially strong impact for women in interracial relationships compared with women in intraracial relationships, but there was no differential impact among men.  相似文献   
55.
The enduring COVID-19 pandemic has gradually transformed our everyday lives. This study focuses on changes in work and family arrangements, with particular focus on changes in domestic help, and examines its impact on the division of domestic labor. Using a social survey of work and the family conducted in November 2020 and May 2021, the results show that from January 2020 (pre-pandemic) to May 2021, approximately 40% of respondents experienced a reduced gender gap for housework and childcare, while a large gender gap is still observed in the absolute frequency of undertaking domestic labor. Some lifestyle changes triggered by the pandemic, such as an increase in the use of takeaways or delivery meals, and the expansion of working from home, are found to be able to contribute a shift toward more equal sharing of domestic labor. However, the fact that the access to such lifestyle changes is more common among those with a relatively high income or high educational background suggests that the lifestyle changes imposed by the pandemic may exacerbate class disparities in the gender gap in domestic labor. Furthermore, the results show that decreased kinship support results in a greater childcare burden being placed on women.  相似文献   
56.

Background

Meconium stained amniotic fluid commonly occurs postdates (?>40 weeks gestation) indicating fetal maturity. Previous literature indicates that different ethnicities mature at different rates.

Aim

To compare the rate of meconium stained amniotic fluid of Australian-born and non-Australian born women.

Methods

A retrospective correlation study design was implemented, using data collected in the birth outcomes system at one tertiary hospital. Data was collected from all women who gave birth to a term (>/=37 weeks gestation), singleton, liveborn baby between January 1st to December 31st, 2014. Maternal country of birth was used for comparison. Categorical data was analyzed using Chi-Square test for Independence. Continuous variables were assessed for normality, and differences were compared using an Independent t-test or a Mann–Whitney U test. All tests were two-tailed and p < 0.05 was considered statistically significant.

Results

3,041 women were included; 1131 Australian-born and 1910 non-Australian born. Meconium stained amniotic fluid occurred more frequently in non-Australian born women compared to Australian-born women (23.5% vs. 19.8 p = 0.02). Their babies were significantly smaller (Mean = 3265 g, Standard Deviation 463.8 vs Mean = 3442 g, Standard Deviation 499.2, p < 0.001), with no difference in gestational length (Mean = 39.4, Standard Deviation 1.28 vs Mean = 39.5, Standard Deviation 1.18, p = 0.06). Increasing gestational age had the strongest association with meconium stained amniotic fluid;?>/=42 weeks gestation occurring 3.52 (95% Confidence Interval: 2.00, 6.22, p = <0.001) more than <40 weeks gestation.

Conclusion

Maternity health services should record ethnicity and region of birth to provide individualised care as women born overseas often have poorer perinatal outcomes when compared to Australian-born women.  相似文献   
57.
People differ in their comfort with tampering with the natural world. Although some see altering nature as a sign of human progress, others see it as dangerous or hubristic. Across four studies, we investigate discomfort with tampering with the natural world. To do so, we develop the Aversion to Tampering with Nature (ATN) Scale, a short scale that is the first to directly measure this discomfort. We identify six activities that people believe tamper with nature (geoengineering, genetically modified organisms, pesticides, cloning, gene therapy, and nanoparticles) and show that ATN scores are associated with opposition to these activities. Furthermore, the ATN Scale predicts actual behavior: donations to an anti-tampering cause. We demonstrate that ATN is related to previously identified constructs including trust in technology, naturalness bias, purity values, disgust sensitivity, aversion to playing God, and environmental beliefs and values. By illuminating who is concerned about tampering with nature and what predicts these beliefs, the ATN Scale provides opportunities to better understand public opposition to technological innovations, consumer preferences for “natural” products, and strategies for science communication.  相似文献   
58.
随着中国环境压力的增加,政府提出了供给侧改革,去产能是改革的主要内容,但是由于产业特征的实时演变,需要对政策进行完善。文章运用模糊C均值算法和支持向量机算法分析现阶段需要进行去产能的产业,结果发现在现行去产能政策中大部分行业是需要去产能的,但煤炭开采和洗选业以及铁路、船舶、航空航天和其他运输设备制造业已不适合继续去产能,同时将化学原料和化学制品制造业加入去产能行列中。  相似文献   
59.
When people need help, what is the process through which they decide whom in their network to turn to? Research on social support has described a process that is deliberative in nature: people determine their needs, assess who in their network has the needed attributes—such as skill, trustworthiness, intimacy, and accessibility—and then activate that tie. Nevertheless, research in behavioral economics and other fields has shown that people make many decisions not deliberatively but intuitively. We examine this possibility in the context of social support by focusing on one factor: accessibility. Although researchers have argued that people weigh the accessibility of potential helpers as they do any other attribute, accessibility may be not only an attribute of the helper but also a condition of the situation. We develop a framework to make this question tractable for survey research and evaluate competing hypotheses using original data on an analytically strategic sample of ∼2000 college students, probing concrete instances of social support. We identify and document not one but three decision processes, reflective, incidental, and spontaneous activation, which differ in the extent to which actors had deliberated on whether to seek help and on whom to approach before activating the tie. We find that while the process was reflective (consistent with existing theory) when skill or trustworthiness played a role, it was significantly less so (consistent with the alternative) when accessibility did. Findings suggest that actors decide whom in their network to mobilize through at least three systematically different processes, two of which are consistent less with either active “mobilization” or explicit “help seeking” than with responsiveness to opportunity and context.  相似文献   
60.
The aim of this study is to determine the risk factors and protective factors of being a victim of couple violence, considering cultural conventions, coping, social support, external attribution and violence in childhood. A non-probabilistic sample of 223 women and 177 men was used. The risk factors in the sample as a whole were being male, the coping strategy of accommodation, violence in childhood and external attribution, while the protective factors were partner support and an active coping style. The study concludes with suggestions for interventions and research.  相似文献   
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