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101.
We propose a multiple imputation method to deal with incomplete categorical data. This method imputes the missing entries using the principal component method dedicated to categorical data: multiple correspondence analysis (MCA). The uncertainty concerning the parameters of the imputation model is reflected using a non-parametric bootstrap. Multiple imputation using MCA (MIMCA) requires estimating a small number of parameters due to the dimensionality reduction property of MCA. It allows the user to impute a large range of data sets. In particular, a high number of categories per variable, a high number of variables or a small number of individuals are not an issue for MIMCA. Through a simulation study based on real data sets, the method is assessed and compared to the reference methods (multiple imputation using the loglinear model, multiple imputation by logistic regressions) as well to the latest works on the topic (multiple imputation by random forests or by the Dirichlet process mixture of products of multinomial distributions model). The proposed method provides a good point estimate of the parameters of the analysis model considered, such as the coefficients of a main effects logistic regression model, and a reliable estimate of the variability of the estimators. In addition, MIMCA has the great advantage that it is substantially less time consuming on data sets of high dimensions than the other multiple imputation methods.  相似文献   
102.
The broad goals of child support policy are to keep children in single-parent families out of poverty and to make sure that their material needs are met. One potentially important, but relatively understudied, set of measures of child well-being are health outcomes. A fixed-effects analysis of data from the Child and Young Adult file of the 1979 National Longitudinal Survey of Youth shows that, conditional upon receipt of some amount of child support, higher payment levels are associated with significantly greater odds of having private health insurance coverage and significantly lower odds of poor or declining health status. These effects persist even after controlling for other factors that are likely to be correlated with child support payments, including total family income and paternal visitation patterns.  相似文献   
103.
104.
This study investigated the longitudinal relation between therapeutic alliance and treatment motivation in a sample of 174 adolescents receiving residential treatment in the Netherlands. Structural equation modeling with a cross-lagged panel design was used to examine the relation between therapeutic alliance and treatment motivation up to 9 months of treatment. Results revealed that autoregressive associations between initial therapeutic alliance and alliance at subsequent time points were significant, whereas for treatment motivation a significant association was found after 6 months, but not after 9 months. Results also showed that a higher level of therapeutic alliance after 3 months was predictive of a higher level of treatment motivation after 6 months. Furthermore, a higher level of therapeutic alliance after 6 months was predictive of a higher level of treatment motivation after 9 months. Implications for research and clinical practice are discussed.  相似文献   
105.
V.A. Knight  P.R. Harper  L. Smith 《Omega》2012,40(6):918-926
This paper proposes new models for locating emergency medical services (EMS) by incorporating survival functions for capturing multiple-classes of heterogeneous patients. The Maximal Expected Survival Location Model for Heterogeneous Patients (MESLMHP) aims to maximize the overall expected survival probability of multiple-classes of patients, whereby different classes could be defined according to agreed patient categories based on response time targets, or by capturing differing medical conditions each with a corresponding survival function. Furthermore, we propose and demonstrate an approximation approach to solving the extended stochastic version of MESLMHP, which utilizes queuing theory to permit the modeling of congestion and utilization at each ambulance station, and does not require assumptions to be made on the utilization of ambulances. Both models are demonstrated using data from the ambulance service in Wales. We show that our multiple outcome measures and survival-maximizing approach, rather than one based on average response time targets alone or a single patient class provides more effective EMS ambulance allocations.  相似文献   
106.
In this paper the relationships between a disruption in parental co-habitation and various categories of adolescent outcomes over multiple time horizons are explored. Using data from the National Longitudinal Study of Adolescent Health (Add Health), we estimated the effects of a change from living with both parents to just one, on academic and employment outcomes, the likelihood to indulge in risky behaviors, mental health outcomes and body mass index measures, from less than 1 year to over 14 years after the change. Propensity score matching methods were used to control for individual characteristics and pre-existing differences in the family environment that may increase the chances of separation, and the results are compared to those obtained using ordinary least squares or probit methods. Results showed evidence of adverse effects of living with one parent in the short term, medium term and long term. Adolescents living with one parent had lower academic achievement in all term lengths, poor mental health in the short to medium term, and were more likely to engage in risky behaviors in the medium to long term.  相似文献   
107.
This discussion paper suggests that there is possibly a divergence of opinion taking place within the field of child and family social work and that the stated positions are influencing how practitioners identify and deal with risks and opportunities afforded by the Internet and social media. The suggested divergence is examined and the conclusion drawn is that what is taking place mirrors the fact that the introduction of any new technology inevitably brings with it division and debate. In seeking to understand the reaction to digital technology, consideration is given to a series of wider social discourses on childhood and risk, which includes the controversial notion that the profession is a harbinger of moral panic and that the management of risk has been broadened from child protection to child safety. The discussion paper concludes by calling for child and family social work practitioners to have a balanced debate that needs to be informed not only by current research but also by an open and honest discussion about personal use and an acknowledgement that there will be difficult moral and ethical questions to work through.  相似文献   
108.
Principal component analysis (PCA) is widely used to analyze high-dimensional data, but it is very sensitive to outliers. Robust PCA methods seek fits that are unaffected by the outliers and can therefore be trusted to reveal them. FastHCS (high-dimensional congruent subsets) is a robust PCA algorithm suitable for high-dimensional applications, including cases where the number of variables exceeds the number of observations. After detailing the FastHCS algorithm, we carry out an extensive simulation study and three real data applications, the results of which show that FastHCS is systematically more robust to outliers than state-of-the-art methods.  相似文献   
109.
The purpose of this study is to analyze the effects of corruption on institutional confidence through testing alternative perceptions-based indexes of corruption. Scholars who have investigated this topic have often employed only indicators of corruption based on experts’ surveys. In this article we also consider a new index of corruption developed aggregating citizens’ perceptions. The first part of the paper explores the levels of corruption perceived by the citizens of EU member states, stressing the differences with the experts’ opinions. The second part tests, through a multivariate analysis, the impact of citizens’ and experts’ perceptions-based indexes of corruption on institutional confidence. The main results show that experts and citizens tend to express similar opinions on the extent of corruption in EU member states though, especially in some countries, these actors present some noticeable differences. Nevertheless, irrespective of the indexes used, more corrupt countries are characterized by lower levels of confidence in parliament and government. This relationship holds even controlling for the presence of reverse causality between corruption and confidence.  相似文献   
110.
Textbooks in the areas of Management Accounting, Finance and Valuation treat taxes very differently. Finance and Valuation increasingly consider tax effects. Management Accounting considers taxes only if they meet certain legal “cost” criteria. These criteria follow tax law rules, but not economic rules and primarily consider tax effects of the local business tax only. This view is also reflected in recent cost accounting regulations. We present evidence from a survey of managers and chambers of commerce, according to which practitioners’ views of whether the local business tax is a cost are heterogeneous. The majority of managers do not consider the local business tax as a cost and do not pass it on to customers. The chambers of commerce however still consider the local business tax as a cost.  相似文献   
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