A new semiparametric Weibull cure rate model: fitting different behaviors within GAMLSS

ABSTRACT

We propose a new semiparametric Weibull cure rate model for fitting nonlinear effects of explanatory variables on the mean, scale and cure rate parameters. The regression model is based on the generalized additive models for location, scale and shape, for which any or all distribution parameters can be modeled as parametric linear and/or nonparametric smooth functions of explanatory variables. We present methods to select additive terms, model estimation and validation, where all computational codes are presented in a simple way such that any R user can fit the new model. Biases of the parameter estimates caused by models specified erroneously are investigated through Monte Carlo simulations. We illustrate the usefulness of the new model by means of two applications to real data. We provide computational codes to fit the new regression model in the R software.     

Authorship Trends in The Analysis of Verbal Behavior: 1982–2016

The Analysis of Verbal Behavior - The Analysis of Verbal Behavior (TAVB) is the only journal focused on theoretical and empirical research in verbal behavior. An assessment of authorship trends can...     

Older People’s Motivations to Engage in Political Organizations: Evidence from a Catalan Study

This study explored the motivations of Catalan older people to engage in political organizations. The sample consisted of 192 people aged 65 and over who were active members of three types of political organizations: neighborhood associations, political parties/trade unions, and single-issue organizations. Their answers to an open-ended question were content analyzed, and a series of Chi-square tests were run to assess the association of the resulting categories with the type of organization in which participants were active. The results show that the motives for engaging in political organizations were mainly focused on introducing changes in the community, although the scope of the changes desired tended to vary. While some participants expressed idealistic motivations, others stated that they become involved in order to stand up for a cause in which they believed. One in six participants was motivated by self-interest, either related to personal growth or to self-protective needs. Motives for participating were related to the type of organization in which participants were active, suggesting that organizations should consider the influence of their own particular context and characteristics in developing recruitment and retention strategies.     

Racemaking in New Orleans: racial boundary construction among ideologically diverse college students

We explore how an ideologically diverse group of white students at Tulane University respond to evidence of racial inequality in post-Katrina New Orleans. In line with prior research, we find commonalities in racialized attitudes and behaviours between students whose racial ideologies otherwise differ. Drawing from anthropological theories of boundary construction and sociological work on colour-blind racism, we argue that the Otherization of non-whites is part of the everyday worldviews and social practices of white Americans. We draw on fieldwork in New Orleans to demonstrate that racist stereotypes and beliefs in racial difference continue to be transmitted within white social spaces. We find that even the most progressive Tulane students are engaged in the construction and reinforcement of symbolic and spatial boundaries between themselves and African Americans. This achieves the purpose for which racial stereotypes were originally constructed – namely, the persistence of racial inequality.     

TimeOut@UCLA: An Intergenerational Respite Care and Workforce Development Program

TimeOut@UCLA is an intergenerational program that recruits undergraduate college students to provide companionship to older adults with early Alzheimer’s or other forms of dementia in a community setting, providing respite for their caregivers. In the program, 86 students and 89 seniors participated from September 2015 to December 2016. This program appears to reinforce positive attitudes about working with older adults among undergraduate students and gives caregivers an innovative option for respite time.     

Un análisis de la relación entre ambiente familiar y delincuencia juvenil

Resumen

En este trabajo se analiza la relación entre las interacciones afectivas y normativas del ambiente familiar, y la conducta delictiva de los adolescentes varones. La muestra del estudio estaba compuesta por tres grupos de adolescentes: no delincuentes, delincuentes no detectados y delincuentes detectados (institucionalizados). Los resultados de los análisis realizados ponen de manifiesto la existencia de diferencias significativas entre las características familiares de delincuentes y no delincuentes. Concretamente, los datos del estudio permiten afirmar que: 1) las variables afectivas parecen más importantes que las referidas a los aspectos normativos para discriminar entre los grupos de sujetos, y 2) entre las variables afectivas serían el apego del hijo hacia los padres y el conflicto familiar las que aparecen como especialmente relevantes para discriminar entre delincuentes y no delincuentes, asociándose un alto nivel de apego/bajo nivel de conflicto con no delincuencia, y un bajo nivel de apego/alto nivel de conflicto con delincuencia.     

Parametric Bayesian inference for Y-linked two-sex branching models

A Y-linked two-sex branching process with blind choice is a suitable model for analyzing the evolution of the number of carriers of two alleles of a Y-linked gene in a two-sex monogamous population where each female chooses her partner from among the male population without caring about his type (i.e., the allele he carries). This work focuses on the development of Bayesian inference for this model, considering a parametric framework with the reproduction laws belonging to the power series family of distributions. A sample is considered given by the observation of the total number of females and males (regardless of their types) up to some generation as well as the number of each type of male in the last generation. Using a simulation method based on the Gibbs sampler, we approximate the posterior distributions of the main parameters of this model. The accuracy of the procedure based on this sample is illustrated by way of a simulated example.     

Tempus Edax Rerum: Measuring the incumbency advantage in the U.S. House of Representatives

Many studies provide valuable insight on the electoral incumbency advantage; however, little work provides insight or an organized theory for how such an advantage develops for career politicians. We develop such a theory, arguing that to understand the incumbency advantage at the time of an electoral victory, it is necessary to consider the length of each specific congressional career. We find that the total share of the incumbent vote received has a curvilinear relationship with the number of years any House Member spends in office. Our findings also result in a better understanding of the incumbency advantage in the U.S. then previous conceptualizations and allows for comparisons of the incumbency advantage across the two Chambers of Congress, other elective offices, and even across democratic political systems.     

Managing ergonomics in the development of rotation between workstations in the automotive industry. A balance between health and traceability of tasks

Abstract When the subject rotation between workstations (job rotation) is inside the organizations it's seemed that technically there are lots of restrictions to the development of an adequate system of rotation. We went from the need for an advanced ergonomic study and even possible restrictions of versatility and training of employees. The implementation of the ideal system of rotation passes through stages of development and research ergonomic study of the level of employee versatility, awareness and discussion with employees, implementation of the proposed system, feedback and audits for maintenance of the ideal sequence and time of rotation. For the success of the project there is a need for multidisciplinary involvement in the areas of manufacturing engineering, industrial engineering, human resources, medical services and manufacturing. Rotation between the tasks may mean that a worker should conduct two or more different activities in different parts of the day (ie. change between activity A and activity B "between 1 hours and 2 hours interval). An important consideration is to ensure that different activities do not present the same ergonomic risk for the same body part. The tracing of the execution of the activity is an important factor for production processes. Thus it is possible to conduct appropriate levels of training for employees and ensure safe and sustainable processes in terms of workers' health, productivity and quality.