Accelerated life regression modelling of dependent bivariate time‐to‐event data

To analyze bivariate time‐to‐event data from matched or naturally paired study designs, researchers frequently use a random effect called frailty to model the dependence between within‐pair response measurements. The authors propose a computational framework for fitting dependent bivariate time‐to‐event data that combines frailty distributions and accelerated life regression models. In this framework users can choose from several parametric options for frailties, as well as the conditional distributions for within‐pair responses. The authors illustrate the flexibility that their framework represents using paired data from a study of laser photocoagulation therapy for retinopathy in diabetic patients.     

The Relationship of Attachment Variables to Career Decision‐Making Self‐Efficacy and Fear of Commitment

The present study indicated that both attachment bonds and self‐rated attachment style were significantly related to fear of commitment and, to a lesser extent, career decision‐making self‐efficacy. Given previous research showing that fear of commitment is related to career indecisiveness and “floundering,” the possible importance of attention to attachment bonds and styles in career counseling is suggested.     

Contributions of Self‐Efficacy Theory to Career Counseling: A Personal Perspective

The author provides a brief overview of A. Bandura's (1977, 1997) self‐efficacy theory, followed by a discussion of the value of this theory to career counselors, which includes particularly useful features of the concept of self‐efficacy and suggestions for its application in career assessment and counseling, with a special focus on group interventions.     

Estimating the Ozone Depletion Potential of Methyl Bromide

Ozone depletion potential (ODP) represents the cumulative ozone depletion induced by a particular halocarbon relative to a reference gas (usually trichlorofluoromethane, CFC-11). We focus on ODP estimation for methyl bromide. Previous attempts at its estimation have assumed that components of the ODP equation are lognormally distributed. By considering a wide range of modeling scenarios, we show that this restriction (which is based on computational convenience rather than experimental evidence) has obscured the true uncertainty in the ODP value. Moreover, when publishing point estimates for the ODP value, previous authors have given either mean or median values. We submit that a more appropriate choice for a point estimate is the mode since the distribution of ODP is skewed and since the mode is by definition, the most likely value. For each modeling scenario considered, modal values are given. In general, we find these ODP point estimates are considerably lower than those published elsewhere.     

The ecology of social networks in four urban neighborhoods

This paper re-examines the question of the social “fabric” of urban neighborhoods on the basis of residents' personal networks. Data were collected on the number, relative intimacy, and spatial distribution of social relationships among residents of two ethnically homogenous and two ethnically heterogenous neighborhoods in a medium-sized city in the midwestern United States. The analysis focused on spatial distributions and variables associated with differences in the average number or intimacy of neighborhood network ties. Herbert Gans had predicted that in heterogenous neighborhoods residential proximity would be a less important factor in social network formation than has previously been reported for socially homogeneous residential settings (especially Festinger et al. 1950). The results from this study indicated that the effects of proximity were more, rather than less, reflected in the spatial distribution of social relationships in the ethnically heterogenous neighborhoods. The face-block was identified as an important socio-spatial unit in all four neighborhoods.