Bayesian Nonparametric Instrumental Variables Regression Based on Penalized Splines and Dirichlet Process Mixtures

We propose a Bayesian nonparametric instrumental variable approach under additive separability that allows us to correct for endogeneity bias in regression models where the covariate effects enter with unknown functional form. Bias correction relies on a simultaneous equations specification with flexible modeling of the joint error distribution implemented via a Dirichlet process mixture prior. Both the structural and instrumental variable equation are specified in terms of additive predictors comprising penalized splines for nonlinear effects of continuous covariates. Inference is fully Bayesian, employing efficient Markov chain Monte Carlo simulation techniques. The resulting posterior samples do not only provide us with point estimates, but allow us to construct simultaneous credible bands for the nonparametric effects, including data-driven smoothing parameter selection. In addition, improved robustness properties are achieved due to the flexible error distribution specification. Both these features are challenging in the classical framework, making the Bayesian one advantageous. In simulations, we investigate small sample properties and an investigation of the effect of class size on student performance in Israel provides an illustration of the proposed approach which is implemented in an R package bayesIV. Supplementary materials for this article are available online.     

Bayesian robustness of credible regions in the presence of nuisance parameters

The problem of finding the most robust γ-level credible region for the parameter of interest in the presence of a nuisance parameter, with respect to a class of ε-contaminated priors, is studied. The case of arbitrary con-taminations is first analyzed; it is proved that the most robust region for the parameter of interest is theγ-level highest marginal likelihood region (forγ ≥ 0.5). Then, the result is extended to any measurable (not necessarily one-to-one) function of the parameter. Finally, the case of contaminations assigning fixed probabilities to the sets of a partition of the parameter space is analyzed and a partial result is given.     

Latent groups and latent traits of participation in bullying via factor mixture analysis: An exploratory study

In this study, we drew on a person-centred approach to explore forms of involvement and roles in bullying. More specifically, we applied Factor Mixture Analysis (FMA) to an in-depth measure of bullying roles, with a view to identifying latent dimensions of participation in bullying and latent groups characterised by differential behavioural patterns. Participants were 899 high school students (51% females) attending the 9th (49%) and 11th grades (51%). The data analysis revealed six latent behavioural dispositions. Four of these overlapped with behavioural patterns typical of previously identified forms of participation in bullying, while two factors shed new light on bullying behaviours. We also identified four latent groups, whose profiles were only partially aligned with the roles previously theorised in the literature.     

e-Social work in practice: a case study

ABSTRACT

This paper presents a theoretical reflection on e-social work by considering a case study: an intervention programme with vulnerable people, included in the services catalogue of a non-governmental organization (NGO), Zaragoza Red Cross Assembly. This programme cares for older people with a home assistance system mediated by information and communication technologies (ICTs). The digital convergence of the Spanish Red Cross and the digitalization of internal processes were accelerated by the use of ICTs as a tool in the aftermath of the 2008 crisis: first, to manage bureaucratic matters; second, to coordinate professionals and third, to interact with users. The text is divided into five sections including an introduction and final remarks. The first section describes the intervention programme and its evolution from a traditional social work vision to an e-social work perspective. The second section describes and analyses the intervention programme and the incorporation of ICTs in this NGO, over more than two decades. The third section describes professional contributions to the implementation and adaptation of social work to new social and technological circumstances and users’ requirements based on these intervention experiences.     

Firm size and appropriability of the results of innovation

This article studies the influence of four dimensions of knowledge (codifiability, observability, complexity and dependency) on two types of appropriation methods: secrecy and other alternative methods (constant incremental improvements, lead time, moving down the learning curve and control of complementary resources) and how the firms’ size modifies these relationships.Based on a sample of 670 innovations developed by Spanish industrial firms, codifiability, observability and dependency were found to be the attributes that marks the effectiveness of both secrecy and the other alternative methods. Dependency marked the effectiveness of alternative methods in large companies and observability and codifiability in small firms.     

Clandestine existences and secret research: eliminating official discrimination in the Canadian military and going public in academia

The 1990s was a notable decade for lesbians and gays in the Canadian military. Two important changes were the 1992 elimination of the official policy permitting discrimination against homosexual service members, and the 1996 introduction of benefits to same-sex partners. These changes radically influenced the psychological day-to-day reality of lesbian and gay military members. Yet, given the military culture, lesbian and gay members only began to come out in significant numbers at the turn of the century. This article presents an overview of our experience with researching the history of lesbians and gays in the Canadian military during the late 1990s and early years of the new century. It reveals the early clandestine nature of our research, and recounts some of the trials, tribulations, resistance, and successes we encountered when dealing with ethics boards and funding sources. It also describes our relationship with the media and how the military actively took steps to stall our efforts. We draw parallels between our experiences as researchers, and those of the lesbian service-members we were interviewing.     

A national evaluation of Safe Schools/Healthy Students: outcomes and influences

The Safe Schools/Healthy Students (SS/HS) Initiative has awarded over $2 billion in grants to more than 350 school districts in partnership with local mental health, law enforcement, and juvenile justice agencies. To estimate the impact of grantee characteristics, grant operations, and near-term outcomes in reducing violence and substance use, promoting mental health, and enhancing school safety, logged odds ratios (LORs) were calculated contrasting Year 3 with Baseline performance from grantee-provided data on seven outcome measures. After comparing grantee performance across outcomes and outcomes across grantees, the LORs were entered as dependent variables in a series of meta-regressions in which grantee characteristics, grant operations, and near-term outcomes were tested after controlling for pre-grant characteristics. Findings indicate that the SS/HS Initiative significantly improved most outcomes, that within-grantee performance varied greatly by outcome, and that random-effects meta-regression appreciably decreased the variance available for modeling. The approach demonstrates that the SS/HS Initiative is effective and that locally collected performance data can be used to estimate grantee success in improving youth outcomes.     

Coping with obsessive relational intrusion and stalking: the role of social support and coping strategies

This study investigated the extent to which social support mediates negative effects of stalking and obsessive relational intrusion (ORI) victimization. A survey of 1,068 respondents indicated that (a) ORI/stalking victimization is positively related to negative symptoms and trauma; (b) five different types of coping responses are positively related to negative symptoms; (c) four domains of social support reveal small but significant negative relationships with negative symptoms; and (d) females are more threatened by unwanted pursuit than male victims, and male pursuers are more threatening than female pursuers. Structural equation modeling indicates that the influence of ORI/stalking on negative symptoms is mediated by the use of coping strategies and the adequacy of social support. Discussion speculates on the functional theoretical value of coping and support processes in managing unwanted pursuit and stalking.     

Policy Implications for Addressing Roma Precarious Migration Through Employment at Home

Roma migration from Romania is often precarious and takes place in circumstances that increase pre‐existent levels of vulnerability. For many, migration is a last resort solution for navigating an insecure economic environment. For others, it has become a source of profit they draw upon, sometimes at the expense of the most vulnerable members of Roma communities. The major challenge this article addresses is how to create the enabling circumstances at home in order to provide alternatives to precarious migration for Roma. Informed by interviews with Roma migrants and with local authorities, this article examines the policy options at local level, addressing Roma precarious migration. It examines the limitations of the current employment policies in relation to Roma in order to identify what seem to work, what sounds promising and what does not work. It advises that job fairs and counselling campaigns are likely to fail, as they do not tackle the structural constraints keeping Roma outside the labour market. Unless linked with realistic employment opportunities, training courses also remain precarious strategies for labour market integration. The article also argues that individualized interventions (including repatriation schemes) are likely to increase community divides. The article supports structural, community‐level measures for tackling unemployment and argues that future policies need to have Roma communities as the ‘unit of intervention’, because the social preconditions for migration are likely to be generated at this level. This policy proposal is grounded in the research finding that an apparently consistent group of Roma migrants, prone to deceitful recruitment and precarious migration, would endorse reasonable and stable economic solutions at home. Yet accepting that circular migration may be inevitable for a number of Roma is an important ingredient when designing policy interventions.     

Perceptions of Communication and Monitoring Technologies Among Older Rural Women: Problem or Panacea?

The purpose of this study was to explore older rural women's perceptions of gerontechnologies, such as in-home monitoring and communication, which may be particularly useful in rural areas where support services are scarce. Forty-three women, ages 60–85 years, participated in focus group discussions. Qualitative analysis uncovered six primary themes: access and reliability, cost, privacy, usability, “use it or lose it” mentality, and caregiver burden. Results suggest that older women in rural areas are open to the potential of gerontechnologies to extend their ability to age in place but are skeptical about their actual implementation.