A longitudinal analysis of infant and senescent mortality using mixture models

We construct a mixture distribution including infant, exogenous and Gompertzian/non-Gompertzian senescent mortality. Using mortality data from Swedish females 1751–, we show that this outperforms models without these features, and compare its trends in cohort and period mortality over time. We find an almost complete disappearance of exogenous mortality within the last century of period mortality, with cohort mortality approaching the same limits. Both Gompertzian and non-Gompertzian senescent mortality are consistently present, with the estimated balance between them oscillating constantly. While the parameters of the latter appear to be trending over time, the parameters of the former do not.     

Infant feeding and asthma: is breast milk best?

Asthma is the most commonly occurring chronic childhood disease in the United States and is the leading cause of hospitalization and missed school days. In this article, I examine whether differences in asthma diagnosis can be attributed to differences in breastfeeding incidence and duration. Using data from the Fragile Families and Child Wellbeing Survey, I examine whether unobserved heterogeneity in the breastfeeding decision plays a role in childhood asthma propensity. I use the recursive bivariate probit framework to account for potential endogeneity by modeling the breastfeeding and asthma equations jointly. Results indicate that after accounting for the unobserved heterogeneity found in infant feeding practices, breastfeeding leads to lower rates of asthma diagnosis in children at age one. Breastfeeding for at least 3 months appears to have the strongest effects in children diagnosed at age one. However, there are no discernible effects of breastfeeding on the incidence of asthma by age three. These results indicate that breastfeeding can result in lower rates of wheezing and better respiratory health in small children.     

Effects of Posture on Newborn Crying

Acoustic properties of the cries of 14 infants were evaluated at both 2 and 4 weeks of age when the infants were lying in a supine position and when they were sitting upright in a car seat. In the upright position, infants' breathing was more rapid and showed less individual variability. The fundamental frequency of their cries increased in the upright position, but this increase was likely attributable to increased arousal or distress, not to posture per se. There were no differences in acoustic measures related to vocal tract shape in the supine versus upright positions. Across age, there was a decline in fundamental frequency. Individual difference stability of most acoustic measures was moderate to high. The importance of postural effects on the acoustic features of cries was discussed.     

The Legal Status of Turks in Germany

Turks in Germany constitute the single largest non-national group living in the member states of the European Union. This essay examines the legal dimensions of their entry, residence and integration in Germany during the 1990s up to 2002. The evidence shows that, despite long-term settlement patterns, Turks in Germany have not achieved a high level of formal inclusion. However, recent policy reforms have already gone some way to improving their situation, and the impact of planned reforms should equally ensure that this process continues in the future.     

Personal Identity and Civic Responsibility: "Rising to the Occasion" Narratives and Generativity in Community Action Student Interns

Twenty–two students in a community action certificate program supplied "rising to the occasion" narratives during summer–long internships. They also filled out measures of generativity. Twenty–one students in an international studies certificate program that also included a summer internship served as a comparison group. Both groups reported equal personal growth from rising to the occasion experiences and no differences on measures of optimism, self–esteem or generativity. However, the community action students linked their personal growth experiences to future community service; a regression analysis also revealed that the best predictor of their stress–related growth was their level of generative concern. No comparable links emerged for the comparison group. Implications for cultivating connections between personal identity and civic responsibility through service–learning are discussed.     

Structure and uncertainty: Graphical models for understanding complex data

Statistics is fundamental to making sense of the complexity of modern science. From the micro-level of the human genome to the macro-level of the universe, scientists need statistical models to help them extract meaning from empirical observations. Graphical models have been used across a wide variety of disciplines for building multivariate probabilistic models to represent, and draw inference about, complex phenomena. Nicky Best and Peter Green explain the ideas behind graphical models and show how they can be used to help tackle the challenges of complex statistical problems.     

The Effect of Gender Context on Children's Social Behavior in a Limited Resource Situation: An Observational Study

Knowing when to compete and when to cooperate to maximize opportunities for equal access to activities and materials in groups is critical to children's social and cognitive development. The present study examined the individual (gender, social competence) and contextual factors (gender context) that may determine why some children are more successful than others. One hundred and fifty‐six children (M age=6.5 years) were divided into 39 groups of four and videotaped while engaged in a task that required them to cooperate in order to view cartoons. Children within all groups were unfamiliar to one another. Groups varied in gender composition (all girls, all boys, or mixed‐sex) and social competence (high vs. low). Group composition by gender interaction effects were found. Girls were most successful at gaining viewing time in same‐sex groups, and least successful in mixed‐sex groups. Conversely, boys were least successful in same‐sex groups and most successful in mixed‐sex groups. Similar results were also found at the group level of analysis; however, the way in which the resources were distributed differed as a function of group type. Same‐sex girl groups were inequitable but efficient whereas same‐sex boy groups were more equitable than mixed groups but inefficient compared to same‐sex girl groups. Social competence did not influence children's behavior. The findings from the present study highlight the effect of gender context on cooperation and competition and the relevance of adopting an unfamiliar peer paradigm when investigating children's social behavior.     

Modelling spatially correlated data via mixtures: a Bayesian approach

Summary. The paper develops mixture models for spatially indexed data. We confine attention to the case of finite, typically irregular, patterns of points or regions with prescribed spatial relationships, and to problems where it is only the weights in the mixture that vary from one location to another. Our specific focus is on Poisson-distributed data, and applications in disease mapping. We work in a Bayesian framework, with the Poisson parameters drawn from gamma priors, and an unknown number of components. We propose two alternative models for spatially dependent weights, based on transformations of autoregressive Gaussian processes: in one (the logistic normal model), the mixture component labels are exchangeable; in the other (the grouped continuous model), they are ordered. Reversible jump Markov chain Monte Carlo algorithms for posterior inference are developed. Finally, the performances of both of these formulations are examined on synthetic data and real data on mortality from a rare disease.     

THE CORRELATES OF HEALTHY FAMILY FUNCTIONING: THE ROLE OF CONSENSUS AND CONFLICT IN THE PRACTICE OF FAMILY THERAPY

The present study explores the relative importance of individual, dyadic and triadic measures of intrafamily functioning in predicting family health. Using self-report data from 78 families, it was found that dyadic measures pertaining to marital quality and parent-child relationships were more powerful predictors than either individual measures of emotional maturity, anxiety, self-esteem or locus of control, or triadic measures of the families' hierarchical alignments. The study also found that while mothers' and fathers' assessments of intrafamily functioning were more important than the childrens' (except for the childrens' view of parent-child relationships), the parents differed in that marital quality was more important to the mothers' evaluations of the family unit while parent-child relationships were more important to the fathers'. Compositely, the findings suggest that family health is a complex multidimensional phenomenon, and that change in a particular dimension of family life may not necessarily be greeted with consensual validation or repudiation by all family members.     

Shared planning: a new foundation for quality criteria.

The Chinese word for crisis has two characters. One for danger and one for opportunity. A crisis is a time for awakening to new perspectives and for asking different questions. The widely touted "liability crisis" in the health care field provides just such a time for new approaches. Perhaps there is a way to establish market mechanisms for decision making that gives expression to the desires and values of consumers while respecting the abilities and preferences of physicians. Quality might then be the result of natural selection or, more accurately, of market demand. Such a system would acknowledge that quality in medicine is not for defining. It's for having. Quality should be obtained in bargaining for services, not in mandates of professional regulation.