Regression analysis of competing risks data via semi-parametric additive hazard model

When the subjects in a study possess different demographic and disease characteristics and are exposed to more than one types of failure, a practical problem is to assess the covariate effects on each type of failure as well as on all-cause failure. The most widely used method is to employ the Cox models on each cause-specific hazard and the all-cause hazard. It has been pointed out that this method causes the problem of internal inconsistency. To solve such a problem, the additive hazard models have been advocated. In this paper, we model each cause-specific hazard with the additive hazard model that includes both constant and time-varying covariate effects. We illustrate that the covariate effect on all-cause failure can be estimated by the sum of the effects on all competing risks. Using data from a longitudinal study on breast cancer patients, we show that the proposed method gives simple interpretation of the final results, when the primary covariate effect is constant in the additive manner on each cause-specific hazard. Based on the given additive models on the cause-specific hazards, we derive the inferences for the adjusted survival and cumulative incidence functions.     

A Moderated Mediation Model of Planned Happenstance Skills,Career Engagement,Career Decision Self‐Efficacy,and Career Decision Certainty

This study examined how college students’ levels of planned happenstance skills influenced the relationships among career engagement, career decision self‐efficacy, and career decision certainty. Moderated mediation analysis was used with a sample of 217 Korean undergraduate students. The results indicated that career decision self‐efficacy mediated the relationship between career engagement and career decision certainty. Moreover, the positive indirect effect of career engagement on career decision through career decision self‐efficacy was strengthened as the level of planned happenstance skills increased. In conclusion, college students’ career engagement strengthens their career decision certainty via career decision self‐efficacy when they have enough planned happenstance skills to discover unexpected career opportunities.     

Construction and Initial Validation of the Planned Happenstance Career Inventory

This study was conducted to develop and initially evaluate the psychometric properties of the Planned Happenstance Career Inventory (PHCI), which aims to assess skill in using chance events to develop career opportunities. After item generation and exploratory factor analysis, 130 original items were reduced to 25 items across 5 factors (5 items for each corresponding factor). Multigroup confirmatory factor analysis confirmed the validity of this 5‐factor structure, and the goodness of fit showed an adequate fit to the observed data for both women and men. Results showed that PHCI subscales correlated moderately and in expected directions with career preparation, career decision‐making self‐efficacy, and career stress. These findings suggest that the PHCI, which assesses 5 dimensions of career‐related planned happenstance skill, shows promise as a useful tool for facilitating understanding of the influence of chance events on career choice behavior.     

What Accounts for the Variations in Nonprofit Growth? A Cross-National Panel Study

Previous studies of nonprofit growth have lamented the lack of cross-national longitudinal data measuring the size of the nonprofit sector across countries, which has made it difficult to assess the current state of knowledge about the nonprofit sector beyond national boundaries. Recent progress in measuring nonprofit growth using panel studies or cross-national data has compensated for the limitations of the existing research, but even the recent data are either country specific or cross sectional in nature. This study takes on the challenge of supplementing the current research by measuring nonprofit growth using internationally comparable longitudinal data. Specifically, this study focuses on whether certain key indicators of the overall state of the economy can be used to predict and explain the size of nonprofit sectors cross-nationally. The overall state of the economy has considerable relevance for nonprofit growth, as it influences the levels of government funding and private philanthropy that benefit the nonprofit sector. The results indicate that the existing theories about the nonprofit sector account for variations in nonprofit growth but are limited in their explanations of the underlying dynamics of such variations beyond national boundaries. Social origins theory is a useful addition that helps to explain cross-national variations in nonprofit growth. Importantly, the interplay among the government, private philanthropy, and the nonprofit sector is dynamic, and its effect on economic indicators varies across nonprofit regime types when sociodemographic variables are controlled.     

父母资助对城市子女住房费用的影响——基于韩国家庭面板数据的实证研究

大城市过高的房价使得很多适婚人群很难仅凭自身经济能力购买住房。因此,很多新婚夫妇向父母寻求经济资助,父母的经济能力和支持程度对新婚夫妇居住的住房条件以及婚房形式产生非常重要的影响。本文利用韩国劳动面板数据分析父母的收入和资产对子女新婚居住形式与费用的影响。分析结果显示,当不区分男女样本进行回归时,子女的收入、教育水平和地区变量等一般认为会影响住房费用的因素在统计上均不显著。这表明新婚夫妇在筹备婚房的过程中所承担的责任往往并不相同。将男女样本分别进行回归时发现父母资产水平对新婚夫妇居住费用产生显著影响。特别是新婚夫妇中男方的住房方式受到父母资产的影响程度高于女方。这反映出婚房筹备方面男性承担主要费用的实际社会现象。而且比起父母当前收入,父母居住的住宅价格对新婚夫妇住宅价格产生更显著的影响,说明父母资产在婚房筹备上起到重要作用。城市居民的住房状况不仅涉及年轻人生活质量,也通过代际关系影响老年人的资产与收入,是关乎民生的重大社会问题。我国政府也面对同样的问题,应该加快建立和完善多层次城镇住房供应体系,对不同收入家庭实行不同的住房供应政策。发展租赁市场作为补充,建立购租并举的住房制度。住房政策与供应模式的创新与改革将有助于解决城市居民购房能力不足的问题,对推动国内消费模式的变化与长期持续中高速经济增长都将产生深远影响。     

Empirical Studies of Child Welfare Training Effectiveness: Methods and Outcomes

Although public child welfare agencies, as well as contracted private providers, conduct extensive amounts of training, the evaluation evidence for effectiveness of training interventions is sparse. This article provides a critical review of published reports of the child welfare training evaluation literature. When we conducted a search of the literature published since 1990, 14 articles met the criteria for inclusion. These articles are reviewed according to: training audience, training duration, research design, sample size, outcome measures, and reported results. Our conclusions identify strengths and weaknesses in evaluation approaches to date and suggest strategies for enhancing the evidence base of this core intervention in child welfare.     

Social process theory of emotion: A dynamic systems approach

In this paper we apply a dynamic systems perspective to infant emotional development. We propose that emotions are not states but self-organizing dynamic processes intimately tied to the flow of an individual's activity in a context. We review data on the relationship between emotional actions and the social context, in particular the development of smiling and laughter. These data are more adequately explained by our perspective than by other theories of emotional development. We provide a model for how emotional processes in early infancy become embedded into sociocultural systems, and suggest new avenues of research on emotional development.     

Imputation using response probability

The authors propose a new ratio imputation method using response probability. Their estimator can be justified either under the response model or under the imputation model; it is thus doubly protected against the failure of either of these models. The authors also propose a variance estimator that can be justified under the two models. Their methodology is applicable whether the response probabilities are estimated or known. A small simulation study illustrates their technique.