Recent migrations from Morocco to Spain

"This study addressed the problem of the Moroccan immigration into Spain within the context of South-North movements, focusing on analyzing provisional data from the last immigrant regularization in the country completed during the end months of 1991."     

Child health,breast-feeding,and survival in Malaysia: a random-effects logit approach

This study examines the possibility that estimation of the effect of breast-feeding on infant survival is affected by selection bias, in that children who are healthier at birth may be more likely to be breast-fed. Data are from the 1976 Malaysian Family Life Survey. "Ordinary logit models for breast-feeding and survival are estimated, and the results suggest that selection is indeed present. For example, children of higher birth weight appear to be more likely to be breast-fed and likely to survive. In addition, weight at birth and the duration of breast-feeding appear to be linked." Using birth weight as an indicator for the child's health, the authors conclude that "the direct influence of breast-feeding on survival remains of overwhelming importance even after corrections for selection bias are made."     

How do risk attitudes affect pro-social behavior? Theory and experiment

Theory and Decision - We explore how risk preferences affect pro-social behavior under uncertainty. We analyze a modified dictator game in which the dictator can, by reducing her own sure payoff,...     

Integrating commercial and residential pickup and delivery networks: A case study

This paper presents a strategic analysis of the network design problem faced by pickup and delivery companies operating in metropolitan areas and serving two or more classes of customers. The focus is on a division that treats commercial and residential customers separately, a situation motivated by their respective geographic densities and the size and frequency of their demand. In constructing driver work areas, it is necessary to take into account expected demand, vehicle capacity, time on the road, and the aspect ratio of the individual territories. This leads to a capacitated clustering problem with side constraints that has been the subject of intense research over the last decade.     

Men and women who like continuous shiftwork are more ‘hardy’: But what does it mean?

Abstract

Continuous shiftworkers of both genders who like shiftwork and report fewer digestive problems have higher scores on hardiness than those who dislike shiftwork. Whether this is a causal, consequential or accidental relationship requires a longitudinal investigation. It is also not clear how far ‘hardiness’ is a personality measure, a behavioural style, a coping strategy, or a consequence of the stress of shiftwork.     

Constrained production lot-size model with trade-credit policy: 'A comparison geometric programming approach via Lagrange'

In this paper our main objective is to investigate a deterministic inventory production lot-size model with a permissible delay in payment under a restriction. We analyse our deterministic inventory model under a restriction which will be assumed as the average inventory level. In fact we use in our analysis two approaches: the geometric programming approach; and the Lagrange method. Then a comparison between these two approaches is performed, which is our aim. Finally we deduce some previously published works of other researchers as special cases.     

Effort-reward imbalance and work-home interference: a two-wave study among European male nurses

ABSTRACT

This one-year follow-up study among 1,421 male nurses from seven European countries tested the validity of the Effort-Reward Imbalance (ERI) model in predicting prospective vital exhaustion and work-home interference. We hypothesised that effort and lack of reward would have both main and interactive effects on future outcomes. Results of structural equation modelling (SEM) showed that effort was positively related to exhaustion and work-home interference, both simultaneously and over time. Lack of reward predicted increased exhaustion at follow-up, but effort-reward imbalance did not influence the outcomes. Additionally, Time 1 exhaustion predicted increased work-home interference and exhaustion at follow-up. These results do not support the ERI model, which postulates a primacy of effort-reward imbalance over main effects. Instead, the findings are in line with dual path models of job stress and work-home interference. Multi-group SEM showed partial cross-cultural metric invariance for the ERI measure of effort, but the ERI measure of rewards showed no metric measurement invariance, indicating its meaning is qualitatively different across cultures. Nevertheless, the main conclusions were markedly similar for each national sub-sample. We discuss the theoretical and practical implications of our study.     

New Data,Strategies, and Insights for Listeria monocytogenes Dose‐Response Models: Summary of an Interagency Workshop, 2011

Listeria monocytogenes is a leading cause of hospitalization, fetal loss, and death due to foodborne illnesses in the United States. A quantitative assessment of the relative risk of listeriosis associated with the consumption of 23 selected categories of ready‐to‐eat foods, published by the U.S. Department of Health and Human Services and the U.S. Department of Agriculture in 2003, has been instrumental in identifying the food products and practices that pose the greatest listeriosis risk and has guided the evaluation of potential intervention strategies. Dose‐response models, which quantify the relationship between an exposure dose and the probability of adverse health outcomes, were essential components of the risk assessment. However, because of data gaps and limitations in the available data and modeling approaches, considerable uncertainty existed. Since publication of the risk assessment, new data have become available for modeling L. monocytogenes dose‐response. At the same time, recent advances in the understanding of L. monocytogenes pathophysiology and strain diversity have warranted a critical reevaluation of the published dose‐response models. To discuss strategies for modeling L. monocytogenes dose‐response, the Interagency Risk Assessment Consortium (IRAC) and the Joint Institute for Food Safety and Applied Nutrition (JIFSAN) held a scientific workshop in 2011 (details available at http://foodrisk.org/irac/events/ ). The main findings of the workshop and the most current and relevant data identified during the workshop are summarized and presented in the context of L. monocytogenes dose‐response. This article also discusses new insights on dose‐response modeling for L. monocytogenes and research opportunities to meet future needs.     

Charisma and organizational change: A multilevel study of perceived charisma,commitment to change,and team performance

What makes people perceive a leader as charismatic, and how do team leaders obtain performance outcomes from their followers? We examine leaders in times of organizational change and investigate the mechanisms through which leaders' change-promoting behaviors are associated with team performance. In a multilevel mediation model, we propose that the indirect relationship between change-promoting behaviors and team performance is sequentially transmitted through followers' perceptions of charisma and followers' commitment to change. A study of 33 leaders and 142 followers provides empirical support for the model, using multilevel structural equation modeling to analyze top-down relationships between leaders and followers and bottom-up relationships between followers and team outcomes. Results suggest that team leaders are perceived as more charismatic when they engage in change-promoting behaviors. These behaviors facilitate team performance through individual followers' perceived charisma and commitment to change.     

Why good practice of OR is not enough—Ethical challenges for the OR practitioner

This paper develops the idea that following rules of good OR practice is necessary, but not sufficient for ethical OR. Several challenges of introducing ethical aspects into OR are discussed, evidencing difficulties and ambiguities in the relationship to be established between the OR practitioner and his/her clients, decision-makers or stakeholders. It shows that neither analysis nor modelling work nor the choice of analytical tools is entirely ethically neutral; incomparability, incommensurability and incertitude must be dealt with. The purpose of this article is to detail several difficulties or dilemmas an OR practitioner may be confronted with in the course of his or her assignment. In such situations, following rules of good practice may not be sufficient to indicate how to act in a morally good way. This paper aims at stimulating reflection by structuring the debate; it may leave the reader unsettled—unsettlement being a result and even aim of many discussions in moral philosophy.