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61.
Fathers' absence is a pattern that shows intergenerational continuity, most notably within disadvantaged populations. The process whereby this pattern is repeated across generations is not well understood. Using data from the Concordia Longitudinal Risk Project, the authors investigated pathways between fathers' absence in 1 generation and the experience of fathers' absence by their children. The current sample included 386 socioeconomically at‐risk individuals across 2 waves of data collection: (a) when they were children and (b) when they were adults with their own children. Analyses based on structural equation modeling revealed that men whose fathers were absent when they were children were more likely to become absent fathers, and women whose fathers were absent when they were children were more likely to have children with absent partners. Indirect pathways between fathers' absence in 2 generations through aggression, education, and substance abuse were illustrated for women. These findings add to the literature suggesting that fathers' absence during childhood has intergenerational effects.  相似文献   
62.
Rapid sexual involvement may have adverse long‐term implications for relationship quality. This study examined the tempo of sexual intimacy and subsequent relationship quality in a sample of married and cohabiting men and women. Data come from the Marital and Relationship Survey, which provides information on nearly 600 low‐ to moderate‐income couples living with minor children. Over one third of respondents became sexually involved within the first month of the relationship. Bivariate results suggested that delaying sexual involvement was associated with higher relationship quality across several dimensions. The multivariate results indicated that the speed of entry into sexual relationships was negatively associated with marital quality, but only among women. The association between relationship tempo and relationship quality was largely driven by cohabitation. Cohabiting may result in poorer quality relationship because rapid sexual involvement early in the romantic relationship is associated with entrance into shared living.  相似文献   
63.
This article addresses the question of why Portugal is an exception among southern European countries in having a high rate of female employment. Cross‐national data show an even greater gap between Portugal and its southern European neighbours in the employment rates for low‐educated women. This article presents case‐based evidence on the work orientations, gender relations and reconciliation strategies of low‐educated women working in the clothing industry in Portugal. The analysis reveals that while economic need plays an important role in their attachment to employment, their work decisions are forged by a complex set of attitudes regarding employment and the family. Traditional values regarding the role of women in the family co‐exist with more modern values regarding their employment participation. Moreover, the institutional arrangements of childcare and reconciliation also appear to be more supportive than might be expected in a southern Europe welfare state. By focusing on a particular group of low‐educated women, the findings suggest that the same welfare policies may have different impacts on the reconciliation strategies of women of different socioeconomic groups.  相似文献   
64.
围绕创新创业环境的内涵,梳理了影响创新创业环境的六类主要因素,归纳潜在指标;对各潜在指标进行"聚类—因子—权重"综合分析,提炼影响创新创业环境的主要因子,构建出以6个一级指标和20个二级指标为核心的创新创业环境评价指标体系,并建立评价模型。以中国各省为样本,对全国31个省级单位的创新创业环境在2014年的状况进行测评排序。依据各省创新创业环境综合得分情况,得出全国31省2014年创新创业环境的地理空间分布图。分地区评价结果显示,东部地区创新创业环境具有明显优势,中部、东北和西部地区发展空间较大。从准则层指出各个地区优化创新创业环境的着力点。  相似文献   
65.
Summary.  Data in the social, behavioural and health sciences frequently come from observational studies instead of controlled experiments. In addition to random errors, observational data typically contain additional sources of uncertainty such as missing values, unmeasured confounders and selection biases. Also, the research question is often different from that which a particular source of data was designed to answer, and so not all relevant variables are measured. As a result, multiple sources of data are often necessary to identify the biases and to inform about different aspects of the research question. Bayesian graphical models provide a coherent way to connect a series of local submodels, based on different data sets, into a global unified analysis. We present a unified modelling framework that will account for multiple biases simultaneously and give more accurate parameter estimates than standard approaches. We illustrate our approach by analysing data from a study of water disinfection by-products and adverse birth outcomes in the UK.  相似文献   
66.
郭晨阳  杨卫军 《西北人口》2009,30(1):72-75,80
建国以来,我国出生率发生了重大转变,随着90年代以来人口出生率的逐年下降,我国高等教育将面临学生数量下滑趋势,未来高等院校将会出现生源不足的困境。但是,由于目前我国高等教育入学率还比较低,加之政府财政时高等教育支持的力度也还有很大提升空阅,因此,尽管出生率会不断下降,但对高等院校整体上生存不会受太大的影响。  相似文献   
67.
Case management services for low-income couples receiving relationship education have been required by federal funding agencies. Studies examining relationship education outcomes for low-income couples have yet to address participant characteristics of those who attend case management services (e.g., distressed vs. nondistressed). Thus, this study examined the influence of baseline relationship satisfaction and demographics on attendance at case management visits for 2,628 low-income, partnered participants who attended relationship education. Findings indicated that participants who reported higher baseline relationship distress attended more family services counselor (FSC) visits. However, when we added demographics to the model, relationship distress no longer predicted FSC visits, whereas income served as a predictor for men and women, with those reporting greater monthly income attending more FSC visits.  相似文献   
68.
In this paper the estimation of high return period quantiles of the flood peak and volume in the Kolubara River basin are carried out. Estimation of flood frequencies is carried out on a data set containing high outliers which are identified by the Rosner’s test. Simultaneously, low outliers are determined by the multiple Grubbs–Beck. The next step involved the usage of the mixed distribution functions applied to a data set from three populations: floods with low outliers, normal floods and floods with high outliers. The contribution of the data set with low outliers is neglected, since it should underestimate the flood quantiles with large return periods. Consequently, the best fitted mixed distribution from the applied types (EV1, GEV, P3 and LP3) was determined by using the minimum standard error of fit.  相似文献   
69.
This research was motivated by our goal to design an efficient clinical trial to compare two doses of docosahexaenoic acid supplementation for reducing the rate of earliest preterm births (ePTB) and/or preterm births (PTB). Dichotomizing continuous gestational age (GA) data using a classic binomial distribution will result in a loss of information and reduced power. A distributional approach is an improved strategy to retain statistical power from the continuous distribution. However, appropriate distributions that fit the data properly, particularly in the tails, must be chosen, especially when the data are skewed. A recent study proposed a skew-normal method. We propose a three-component normal mixture model and introduce separate treatment effects at different components of GA. We evaluate operating characteristics of mixture model, beta-binomial model, and skew-normal model through simulation. We also apply these three methods to data from two completed clinical trials from the USA and Australia. Finite mixture models are shown to have favorable properties in PTB analysis but minimal benefit for ePTB analysis. Normal models on log-transformed data have the largest bias. Therefore we recommend finite mixture model for PTB study. Either finite mixture model or beta-binomial model is acceptable for ePTB study.  相似文献   
70.
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