Extending Bayesian back-calculation to estimate age and time specific HIV incidence

Lifetime Data Analysis - CD4-based multi-state back-calculation methods are key for monitoring the HIV epidemic, providing estimates of HIV incidence and diagnosis rates by disentangling their...     

Using the Shapley Decomposition to Disentangle the Impact of Circumstances and Efforts on Health Inequality

Following previous work on inequality in health opportunity, this paper attempts to determine the contribution of circumstances, efforts and lifestyle, and demographic variables to the overall inequality in health in Luxembourg. Health is measured via the answers given to a question on self-assessed health and is considered as an ordinal variable. The educational level of each parent, the financial situation of the family during childhood, the area of birth of the individual, and of his/her parents, and the year of immigration are considered as circumstances. Effort and lifestyle variables are proxied by information on the educational level of the individual, whether he/she smoked and whether he/she had a physical activity on a regular basis. Sex and age are considered as demographic variables. To solve the issue of correlation between circumstances and effort and lifestyle the estimation is implemented in two stages. In the first stage, each effort and lifestyle variable is regressed in a separate equation against the vector of circumstances and demographic variables and, in a second stage, the individual health status is regressed against the vector of circumstances and demographic variables along with the estimated residuals of the effort equations described previously. The respective impacts of the three categories of explanatory variables (circumstances, effort and lifestyle and demographic variables) on health inequality are derived via a Shapley decomposition of the likelihood ratio of the health ordered logit regression. It appears that differences in circumstances and effort and lifestyle explain each around a quarter of this likelihood ratio.     

Going to work without educational qualifications: school-to-work transitions of early school leavers in Belgium

ABSTRACT

Risks of exclusion can occur in multiple forms and start early in life. Early school leavers are especially at risk of social exclusion as this is strongly related to turbulent school-to-work-transitions. These young people often find themselves in low-qualified work or unemployment. In this article, we explore the labour market experiences of early school leavers in Flanders, Belgium. In total, 15 in-depth interviews were conducted with nine early school leavers and analysed following a grounded theory approach. Our results demonstrate the difficulties early school leavers encounter in their transitions from school to work and their precarious situation in the labour market. Of particular relevance are the insights gained in revealing the perspectives of young people on the importance of educational qualifications, work experience and participation in the labour market, as well as the strategies they develop to enter the labour market without educational qualifications.     

Trust games: A meta-analysis

We collect data from 162 replications of the Berg, Dickhaut, and McCabe Investment game (the “trust” game) involving more than 23,000 participants. We conduct a meta-analysis of these games in order to identify the effect of experimental protocols and geographic variation on this popular behavioral measure of trust and trustworthiness. Our findings indicate that the amount sent in the game is significantly affected by whether payment is random, and whether play is with a simulated counterpart. Trustworthiness is significantly affected by the amount by which the experimenter multiplies the amount sent, whether subjects play both roles in the experiment, and whether the subjects are students. We find robust evidence that subjects send less in trust games conducted in Africa than those in North America.     

Systems innovation manager

Each year organizations spend a significant amount of money developing new products and processes in an effort to satisfy customer demands and manufacture high-quality products efficiently. Both development processes - product and process, are complex, resource intensive and thrive on innovation. They demand a variety of skills and resources, but in particular, participation among all staff in generating ideas, managing projects and implementing change. There are currently a number of software tools and methods that facilitate change in a systems environment. These range from complex modelling tools to information management tools. The tools have been developed around paradigms, e.g. world class manufacturing, total quality management and business process reengineering. They are often complex, requiring the efforts of skilled designers and managers. Current thinking within a systems environment reflects a more participative and less specialist approach to managing innovation and change. There is a need to create compromise between detailed project engineering and good management practice. This paper introduces a new paradigm centred on good management practice, and identifies the critical issues in systems innovation and change. The paradigm is articulated through a series of change levers and a methodology that guides managers and designers. It is supported by a series of software tools that together bring innovation management to life within the industrial organization.     

Collaborative evaluation and market research converge: an innovative model agricultural development program evaluation in Southern Sudan

In June and July 2006 a team of outside experts arrived in Yei, Southern Sudan through an AID project to provide support to a local agricultural development project. The team brought evaluation, agricultural marketing and financial management expertise to the in-country partners looking at steps to rebuild the economy of the war ravaged region. A partnership of local officials, agricultural development staff, and students worked with the outside team to craft a survey of agricultural traders working between northern Uganda and Southern Sudan the steps approach of a collaborative model. The goal was to create a market directory of use to producers, government officials and others interested in stimulating agricultural trade. The directory of agricultural producers and distributors served as an agricultural development and promotion tool as did the collaborative process itself.     

It Takes Two to Fight in School,Too: A Social Relations Model of the Psychometric Properties and Relative Variance of Dyadic Aggression and Victimization in Middle School

Aggressive behavior has been well studied in terms of interindividual differences among aggressors and victims, but has been understudied, especially within naturalistic contexts, in terms of aggressor–victim relationships. The social relations model (SRM) is a powerful conceptual and analytic tool for studying dyadic phenomena, and we describe the use of multivariate SRM to study aggression. Boys and girls (N = 210) in middle schools (sixth and seventh grades) completed a newly created dyadic aggression and victimization inventory (DAVI). Results support the reliability and validity of the DAVI in assessing inter‐individual and inter‐dyadic differences in aggression and victimization. Occurrences of aggression were accounted for primarily by inter‐dyadic variability, indicating the importance of considering aggressor–victim relationships. We discuss the implications of this relationship focus for future research and intervention efforts.     

The impact of acquisitions on firm performance: A review of the evidence

This paper presents a review of empirical research on the impact of acquisitions on firm performance. The evidence suggests that, in the short run, acquisitions have at best an insignificant impact on shareholder wealth. Long‐run performance analysis reveals overwhelmingly negative returns, while the evidence using accounting performance measures is mixed. The review also examines the impact of bid characteristics on performance. The acquisition of hostile targets, transactions that are paid for with cash and acquisitions of larger targets are associated with superior (or at least less negative) performance, while there is mixed evidence on the benefits of related acquisitions. A number of recent studies find that acquirers with superior pre‐bid performance tend to experience significant underperformance in the post‐bid period.