A generalized predictive criterion for model selection

Given a random sample from some unknown model belonging to a finite class of parametric models, assume that the estimate of the density of a future observation is of interest San Martini & Spezzaferri (1984) proposed for this problem a predictive criterion based on the logarithmic utility function. The present authors investigate a generalization of this criterion that uses as a loss function an element of the class of α‐divergences discussed by Ali & Silvey (1966) and Csiszár (1967). They also discuss briefly the case in which the class of models considered is not exhaustive.     

Sexual Offending in Adolescence: A Comparison of Sibling Offenders and Nonsibling Offenders across Domains of Risk and Treatment Need

Sibling sexual offending has received limited empirical attention, despite estimates that approximately half of all adolescent-perpetrated sexual offenses involve a sibling victim. The present study addresses this gap by examining male adolescent sibling (n = 100) and nonsibling offenders (n = 66) with regard to maltreatment histories and scores on two adolescent risk/need assessment instruments, the ERASOR and YLS/CMI. Adolescents who sexually abused a sibling, versus a nonsibling, were more likely to have histories of sexual abuse and been exposed to domestic violence and pornography. There were no group differences on ERASOR and YLS/CMI scales. This study adds to the limited discourse on sibling sexual offending and the larger literature on the heterogeneity of adolescents who have sexually offended.     

Centacare in the Northern Territory

Abstract

At the present time, social work in England finds itself at the crossroads. Against a backdrop of economic globalisation, it has been caught up in New Labour's modernising policy discourse that has recast social justice in terms of opportunity, inclusion, and “choice”. More recently, this has been extended by the introduction of a “respect agenda”, a reaction to the loss of community cohesion and the rise in antisocial behaviour. In the present article, two alternative paradigmatic responses are explored reflecting a debate between evidence-based practice (EBP) and critical practice (CP). These may be juxtaposed because they offer different visions of what social work could become in the future while providing two important reference points against which current practice may be judged. Whereas the former has been depicted as a “search for certainty” that largely complements the modernising discourse, CP works with both certainty and uncertainty in the quest for more emancipatory change. In practice, English social workers may manage such contradictions by looking down both roads and incorporating elements of both in their practice: adopting elements of EBP to justify their interventions and become more research minded while embracing aspects of CP to engage with structural issues that lie at the root of injustice.     

Weak ties and the core discussion network: Why people regularly discuss important matters with unimportant alters

Researchers have paid increasing attention to the core discussion network, the set of friends and family people turn to when discussing important matters. For nearly thirty years, social network researchers have argued that the network is composed of ego's closest or most important alters. This assumption, however, has not been tested empirically. Using original data on an online representative quota survey of 2000 respondents, I find that 45% of the core discussion network is composed of people whom respondents do not consider important to them. In fact, the core discussion network includes doctors, co-workers, spiritual leaders, and other alters whom ego confides in without feeling emotionally attached to. I examine what respondents consider important matters and why they approach weak ties to discuss these. Placing emphasis on the process through which ego mobilizes alters, I develop two theoretical perspectives, which focus on how people identify those appropriate to a topic and how they respond to opportunities in interactional contexts. Findings suggest that ego discusses important matters with non-close alters at times because they are known to be knowledgeable (targeted mobilization) and at times because they are available when important issues arise (opportune mobilization). Results suggest that recent findings about changes in the core discussion network of Americans are consistent with several different possibilities about the nature of strong ties, including those in which there has been no change at all.     

Ethnography Upgraded

Qualitative Sociology - The basic practice of ethnography has essentially remained unchanged in hundreds of years. How has online life changed things? I contrast two transformative inventions, the...     

Connectivity‐informed adaptive regularization for generalized outcomes

One of the challenging problems in neuroimaging is the principled incorporation of information from different imaging modalities. Data from each modality are frequently analyzed separately using, for instance, dimensionality reduction techniques, which result in a loss of mutual information. We propose a novel regularization method, generalized ridgified Partially Empirical Eigenvectors for Regression (griPEER), to estimate associations between the brain structure features and a scalar outcome within the generalized linear regression framework. griPEER improves the regression coefficient estimation by providing a principled approach to use external information from the structural brain connectivity. Specifically, we incorporate a penalty term, derived from the structural connectivity Laplacian matrix, in the penalized generalized linear regression. In this work, we address both theoretical and computational issues and demonstrate the robustness of our method despite incomplete information about the structural brain connectivity. In addition, we also provide a significance testing procedure for performing inference on the estimated coefficients. Finally, griPEER is evaluated both in extensive simulation studies and using clinical data to classify HIV+ and HIV? individuals.     

An integrated nurse staffing and scheduling analysis for longer-term nursing staff allocation problems

The efficient and effective management of nursing personnel is of critical importance in a hospital's environment comprising a vast share of the operational costs. The adopted nurse workforce practices and policies highly affect the nurses' working conditions and the provided quality of care. Policy decisions on the staffing level have an impact on the outcome of the scheduling level and vice versa. Isolated reasoning typically leads to suboptimal decisions often resulting in ineffective outcomes of care. In order to overcome these inefficiencies, we propose in this paper a new integrative nurse staffing and shift scheduling approach. We test and assess the benefits of our approach in a reallife environment. Moreover, we examine the impact of several personnel policies on the staffing decision.