Proportional hazards models: a latent competing risk approach

We propose a novel semiparametric version of the widely used proportional hazards survival model. Features include an arbitrarily rich class of continuous base-line hazards, an attractive epidemiological interpretation of the hazard as a latent competing risk model and trivial handling of censoring. Models are fitted by using a data augmentation scheme. The methodology is applied to a data set recording times to first hospitalization following clinical diagnosis of acquired immune deficiency syndrome for a sample of 169 patients.     

Measuring changes in interagency collaboration: an examination of the Bridgeport Safe Start Initiative

This paper describes the evaluation of interagency collaboration in a network of child-serving providers as part of the evaluation of the Bridgeport Safe Start Initiative (BSSI). In line with the system of care approach, the objectives of BSSI included reducing fragmentation of efforts and delivering integrated services to families of young children exposed to or at risk of exposure to family violence. Interagency collaboration was examined via social network and focus group data collected at three time points starting at baseline. Network analysis findings suggest that over time the network structure became consistent with BSSI's vision of an ideal collaborative network structure. Focus group findings, however, present a more complex picture of the status of collaboration. This paper sheds light on approaches and challenges to measuring interagency collaboration in a service delivery system and communicating social network analysis findings to stakeholders in a way that is accessible and useful.     

Reciprocal relationships among alcohol use, risk perception, and sexual victimization: a prospective analysis

OBJECTIVE: The authors' purpose in this study was to assess longitudinally the relationships among alcohol use, risk perception, and sexual victimization. PARTICIPANTS: Three hundred and seventy-two women from 2 midsized universities made up the sample. METHODS: Participants filled out questionnaires regarding history of sexual victimization, alcohol use, and perceived personal risk for sexual assault in the following 2 months. The authors then reassessed participants at 2 follow-up periods. RESULTS: The pattern of results suggested that that the relationship between alcohol use and sexual victimization was complex and that alcohol use may moderate the relation between history of victimization and revictimization for women with sexual assault histories. In particular, results indicated an increase in risk for sexual revictimization with increases in alcohol use for women with a history of sexual victimization. The data did not, however, support a reciprocal relationship between sexual assault and drinking (eg, in that a sexual victimization during one time period did not predict drinking behaviors in subsequent time periods). CONCLUSIONS: These results underscore the importance of both alcohol and sexual assault programming on college campuses.     

Index to Volume 35

This Field Note presents a follow-up to a pilot study that explored pre-field placement anxiety for 1st-year MSW students. Previous studies report that students experience significant anxiety as they anticipate their field placement, and research indicates that anxiety has the potential to affect learning. A sample of 204 students reported moderate levels of anxiety, comparable to previous findings. Older students, and those with prior work and classroom experience, reported significantly less anxiety. Students described specific concerns but also viewed anxiety as an expectable response with positive connotations for enhanced learning. Implications for social work education and future research are discussed.     

Etherapy: A Training Program for Development of Clinical Skills in Distance Psychotherapy

ABSTRACT

This article describes a project by the Virtual Teaching and Cyberpsychology Laboratory of the National Autonomous University of Mexico developed to (1) implement a teaching program for clinical psychology students to learn therapeutic skills in providing online psychological services; (2) evaluate the students' acquisition of knowledge and skills in diagnosis via the Internet, case formulation of treatment, and adherence to treatment protocols; and (3) incorporate technologies for creating training settings and online professional services in order to develop the students' clinical competency in this treatment modality. A pilot study was conducted with 17 clinical psychology students in the first phase of the teaching program and 6 students during the second phase. Preliminary results indicate that students increased knowledge of Internet-based clinical interventions and improved in clinical skills. It is necessary to continue the evaluation of the teaching program with larger samples, and further research is suggested.     

Ethnic,gender, and length‐of‐residency influences on sexual knowledge and attitudes

We examined potential differences in sexual knowledge and attitudes between 702 Canadian undergraduates of Asian (n = 356) and European (n = 346) ancestry. We also examined potential influences of length of residency in Canada on these variables among Asians, and the role of gender both across and within ethnic groups. The primary purpose was to examine whether length of exposure to North American sexual values influences sexual knowledge or attitudes among Asians living in Canada. Results revealed that compared to Europeans, Asians held more conservative sexual attitudes and demonstrated significantly less sexual knowledge. Recent Asian immigrants were significantly more likely than Canadian‐born or long‐term Canadian residents to hold conservative sexual attitudes on a number of sexuality items. Among Asians and Non‐Asians, males reported more negative attitudes toward homosexuals than did females; females held more conservative sexual attitudes toward uncommitted sexual relations than did males. The findings provide partial support for a cultural explanation of the frequently reported finding that, compared with North Americans, Asians are more restricted in their expression of sexuality.     

Approximating cross-validatory predictive evaluation in Bayesian latent variable models with integrated IS and WAIC

Looking at predictive accuracy is a traditional method for comparing models. A natural method for approximating out-of-sample predictive accuracy is leave-one-out cross-validation (LOOCV)—we alternately hold out each case from a full dataset and then train a Bayesian model using Markov chain Monte Carlo without the held-out case; at last we evaluate the posterior predictive distribution of all cases with their actual observations. However, actual LOOCV is time-consuming. This paper introduces two methods, namely iIS and iWAIC, for approximating LOOCV with only Markov chain samples simulated from a posterior based on a full dataset. iIS and iWAIC aim at improving the approximations given by importance sampling (IS) and WAIC in Bayesian models with possibly correlated latent variables. In iIS and iWAIC, we first integrate the predictive density over the distribution of the latent variables associated with the held-out without reference to its observation, then apply IS and WAIC approximations to the integrated predictive density. We compare iIS and iWAIC with other approximation methods in three kinds of models: finite mixture models, models with correlated spatial effects, and a random effect logistic regression model. Our empirical results show that iIS and iWAIC give substantially better approximates than non-integrated IS and WAIC and other methods.     

Counterdiagonal/nonpositive tail dependence in Vine copula constructions: application to portfolio management

Statistical Methods & Applications - Accurately modelling the dependence structure between financial assets in a portfolio optimization framework has attracted growing attention in statistical...     

Developing talent with an integrated knowledge-sharing mechanism: an exploratory investigation from the Chinese human resource managers' perspective

Drawing from knowledge sharing and social exchange theory, the paper explores the connection between talent development and knowledge-sharing mechanisms. Based on a preliminary investigation of reviewing the learning experience and career development of 20 Chinese HR practitioners, the findings confirm that incorporating a knowledge-sharing socialization mechanism with talent development programs has a nurturing and supporting effect on learning and development. The mechanism can be used to facilitate organization-wide knowledge sharing and support both organization-led and self-managed talent development programs.