Effects of unmeasured heterogeneity in the linear transformation model for censored data

We investigate the effect of unobserved heterogeneity in the context of the linear transformation model for censored survival data in the clinical trials setting. The unobserved heterogeneity is represented by a frailty term, with unknown distribution, in the linear transformation model. The bias of the estimate under the assumption of no unobserved heterogeneity when it truly is present is obtained. We also derive the asymptotic relative efficiency of the estimate of treatment effect under the incorrect assumption of no unobserved heterogeneity. Additionally we investigate the loss of power for clinical trials that are designed assuming the model without frailty when, in fact, the model with frailty is true. Numerical studies under a proportional odds model show that the loss of efficiency and the loss of power can be substantial when the heterogeneity, as embodied by a frailty, is ignored. An erratum to this article can be found at     

The deprivation experienced by disabled asylum seekers in the United Kingdom: symptoms,causes, and possible solutions

Disabled asylum seekers have been found to often experience extreme deprivation. Possible causes and solutions are explored, drawing on the experiences of disabled asylum seekers themselves as well as on a series of interviews with people working in the asylum and immigration sector. It is suggested that action is required to reduce immediate suffering, but that systemic change is needed to address the causes of this deprivation.     

Anthropological Theories of Low-Wage Work

This review assesses the use of anthropological theories in the examination of low-wage work. Due to the vast differences existing between different cultures in low-wage work, this review focuses on theories that have been applied in Western, and mainly American, contexts. There are primarily three fields from which this literature is drawn: economic anthropology, gender and race anthropology, and theories of power—the last integrates all these theories. Differences and controversies over the applicability of these theories are also highlighted. The review concludes with a conceptual map describing the interrelatedness of these theories and how they explain the realities of low-wage workers.     

How do International Volunteering Characteristics Influence Outcomes? Perspectives from Partner Organizations

This study examines how different types of international volunteering influence common program outcomes such as building organizational capacity, developing international relationships, and performing manual labor. Survey responses were collected from 288 development-oriented volunteer partner organizations operating in 68 countries. Data on the duration of volunteer service, the volunteers’ skill levels, and other variables were used to develop a rough typology of international volunteering. Binary logistic regression models then assessed differences in outcomes across five volunteering types. Findings suggest that future research needs to be more precise about how the nuances and complexity of diverse forms of international volunteering influence outcomes.     

“Know What to Do If You Encounter a Flash Flood”: Mental Models Analysis for Improving Flash Flood Risk Communication and Public Decision Making

Understanding how people view flash flood risks can help improve risk communication, ultimately improving outcomes. This article analyzes data from 26 mental models interviews about flash floods with members of the public in Boulder, Colorado, to understand their perspectives on flash flood risks and mitigation. The analysis includes a comparison between public and professional perspectives by referencing a companion mental models study of Boulder‐area professionals. A mental models approach can help to diagnose what people already know about flash flood risks and responses, as well as any critical gaps in their knowledge that might be addressed through improved risk communication. A few public interviewees mentioned most of the key concepts discussed by professionals as important for flash flood warning decision making. However, most interviewees exhibited some incomplete understandings and misconceptions about aspects of flash flood development and exposure, effects, or mitigation that may lead to ineffective warning decisions when a flash flood threatens. These include important misunderstandings about the rapid evolution of flash floods, the speed of water in flash floods, the locations and times that pose the greatest flash flood risk in Boulder, the value of situational awareness and environmental cues, and the most appropriate responses when a flash flood threatens. The findings point to recommendations for ways to improve risk communication, over the long term and when an event threatens, to help people quickly recognize and understand threats, obtain needed information, and make informed decisions in complex, rapidly evolving extreme weather events such as flash floods.     

A Qualitative Analysis of College Women's Leaving Processes in Abusive Relationships

Abstract

Objective: This study assessed the process of leaving an abusive dating relationship utilizing a qualitative design. Methods: Participants included 123 college women in abusive dating relationships who participated at the beginning and end of a 10-week academic quarter. Results: Qualitative content analyses were used to analyze the transcribed responses to an open-ended question about women's leaving processes over the interim period. A variety of categories and themes emerged for women in different stages of the leaving process, consistent with the Transtheoretical Model of Change and Investment Model. Data also underscored women's lack of acknowledgment, minimization, and normalization of abuse. Conclusions: These data demonstrate the importance of dating violence intervention and prevention programming on college campuses and offer information that may be useful to college health providers who assist women in abusive dating relationships.     

Selection of cost-optimal 2k−p fractional factorials

Selecting an optimal 2^k?pfractional factorial is structured as a mathematical programming problem. An algorithm is defined for the solution, and the case of additive costs is shown to have a known solution for resolution III designs.