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.     

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.     

Public-Private Partnership Contractual Design: A Computational Model of the Moral Hazard with Lotteries

Public-Private Partnership (PPP) is a new model of public management which consists of the contractual relationship between public and private entities. In particular, PPPs enable risk share between public and private sectors making the asymmetric information problem in a contractual arrangement more evident. The aim of this paper was to study a moral hazard problem applied to PPP contracts. To achieve this objective, a PPP computational contractual model including the moral hazard with lotteries was developed to assess how contractual changes could affect the optimum behavior of arrangement members. Simulations indicate that projects with higher economic value should attract more qualified firms, which may be why the companies expend more effort. To deal with possible contractual contingencies and try to minimize the moral hazard problem, the government could draw up more flexible contracts in order to include possible necessary changes and punish unwanted or improper consortium behavior.     

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.     

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...     

Towards sustainability by aligning operational programmes and sustainable performance measures

Abstract

In the last decades, sustainable concerns have increasingly gained importance to organizational survival, and Lean/Six Sigma approaches are becoming more and more outstanding in order to improve sustainability performance. This article aims to evaluate the degree of importance of sustainable performance measures of Brazilian organizations and to propose guidelines to achieve sustainability by aligning these measures with operational improvement programmes. Multiple data collection methods were applied as theoretical literature review, questionnaire survey and semi-structured interviews with industry professionals and academic researchers. The findings show that it is the corporate responsibility to focus their efforts on both operational improvement programmes and sustainable initiatives in order to achieve better environmental protection, corporate reputation, quality management, cost performance and suppliers relations, as they are considered to be more important on organizational sustainability.     

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.     

Bioactive compounds of the Mediterranean diet and prostate cancer

Abstract

Objective: The purpose of this review is to examine the evidence on the effects of bioactive constituents of the Mediterranean diet (MeDi) on prostate cancer (PCa) risk.

Methods: The search for articles came from extensive research in the following databases: PubMed, Scopus, and Web of Science. We used the search terms “Mediterranean diet,” “lycopene,” “vitamin E,” “vitamin C,” “Selenium,” “resveratrol,” “prostate cancer,” and combinations, such as “lycopene and prostate cancer” or “resveratrol and prostate cancer.”

Results: Numerous studies investigating the effect of various dietary nutrients on PCa have suggested that selenium is probably the most promising. Several studies reported reduced PCa risk associated with vitamin C and E intake, while other studies reported no association. Lycopene inhibits cell proliferation and inducts apoptosis, thus protecting against cancer. Also, it has been found in various in vivo and in vitro studies that resveratrol, inhibits PCa development.

Conclusions: The high content of bioactive phytochemicals in the MeDi is of particular interest in the prevention of PCa. Further large-scale studies are required to clarify the effect of MeDi bioactive compounds on prostate health, in order to establish the role of this diet in the prevention of PCa.     

The logic of counterfactual analysis in case‐study explanation

In this paper, we develop a set‐theoretic and possible worlds approach to counterfactual analysis in case‐study explanation. Using this approach, we first consider four kinds of counterfactuals: necessary condition counterfactuals, SUIN condition counterfactuals, sufficient condition counterfactuals, and INUS condition counterfactuals. We explore the distinctive causal claims entailed in each, and conclude that necessary condition and SUIN condition counterfactuals are the most useful types for hypothesis assessment in case‐study research. We then turn attention to the development of a rigorous understanding of the ‘minimal‐rewrite’ rule, linking this rule to insights from set theory about the relative importance of necessary conditions. We show why, logically speaking, a comparative analysis of two necessary condition counterfactuals will tend to favour small events and contingent happenings. A third section then presents new tools for specifying the level of generality of the events in a counterfactual. We show why and how the goals of formulating empirically important versus empirically plausible counterfactuals stand in tension with one another. Finally, we use our framework to link counterfactual analysis to causal sequences, which in turn provides advantages for conducting counterfactual projections.