Demographic Determinants of Infant and Early Child Mortality: A Comparative Analysis

In this paper we examine the relative importance of a number of demographic determinants of infant and early child mortality using information from 39 World Fertility Survey countries. We include sex of the child, age of the mother at the time of the birth, birth order, mother's educational level and a number of indicators of spacing of adjacent births among the correlates of chances of survival for children below the age of five years. Mortality of firstborn children and of those born to teenage mothers is shown to be higher than average; that of later children and those of older mothers was not much higher than average, once other factors are controlled. Effects of poor birth-spacing persist even after other factors have been controlled, and are similar where a sib was born during the two years preceding the birth of the child, regardless of the survival status of that sib; however, mortality was higher when that sib had died, due to increased familial risks of mortality. Rapid subsequent births also raise mortality for their earlier sibs. The findings are generally remarkably consistent in a wide range of countries and associated mortality conditions, although attention is drawn to a few interesting geographically clustered exceptions which deserve further investigation. The study leaves little room for doubt that poor child-spacing is clearly linked to decreased survival chances.     

Migration and mobility on the Amazon frontier

Migration patterns within tropical forest frontiers are highly complex and multidirectional, with movements to, from, and within these regions likely driven by different macro and micro factors. As such, several different conceptual models have been suggested to explain these dynamics. This paper uses data from a panel survey of households in a frontier region of the western Brazilian Amazon along with “second hand” reports on where people have moved to evaluate these conceptual models. Our rich data set, collected over nearly a decade from hundreds of households, allows us to compare households who arrived at different ages to assess predictions of the life cycle hypothesis; those who have been in the state (or on their properties) for different numbers of years to investigate the turnover hypothesis; those who arrived with different levels of capital to examine path dependence as suggested by conceptual models that focus on wealth dynamics; and the destination and purpose for moves from and within the study region to look for evidence of the frontier expansion hypothesis. We do not find any evidence for the turnover hypothesis, perhaps due to the favorable biophysical and market conditions in our study region. However, patterns in this region are consistent with all of the other conceptual models, reflecting the overlapping theoretical foundations of the models, and the complexity of migration and mobility on the frontier.     

Maternal Education, Birth Weight, and Infant Mortality in the United States

This research determines whether the observed decline in infant mortality with socioeconomic level, operationalized as maternal education (dichotomized as college or more, versus high school or less), is due to its “indirect” effect (operating through birth weight) and/or to its “direct” effect (independent of birth weight). The data used are the 2001 U.S. national African American, Mexican American, and European American birth cohorts by sex. The analysis explores the birth outcomes of infants undergoing normal and compromised fetal development separately by using covariate density defined mixture of logistic regressions (CDDmlr). Among normal births, mean birth weight increases significantly (by 27–108 g) with higher maternal education. Mortality declines significantly (by a factor of 0.40–0.96) through the direct effect of education. The indirect effect of education among normal births is small but significant in three cohorts. Furthermore, the indirect effect of maternal education tends to increase mortality despite improved birth weight. Among compromised births, education has small and inconsistent effects on birth weight and infant mortality. Overall, our results are consistent with the view that the decrease in infant death by socioeconomic level is not mediated by improved birth weight. Interventions targeting birth weight may not result in lower infant mortality.     

Development of the Carers’ Alert Thermometer for Young Carers (CAT-YC) to Identify and Screen the Support Needs of Young Carers: A Mixed Method Consensus Study

Child and Adolescent Social Work Journal - This paper reports on a multi-phased, mixed-method consensus-based study conducted with young carers in the UK aged 11–18, and health, social care...     

Peer Pressure

We present a model where agents care about their neighbors' actions and can pressure them to take certain actions. Exerting pressure is costly for the exerting agent and it can impact the pressured agents by either lowering the cost of taking the action (which we call “positive pressure”) or else by raising the cost of not taking the action (which we call “negative pressure”). We show that when actions are strategic complements, agents with lower costs for taking an action pressure agents with higher costs, and that positive pressure can improve societal welfare. More generally, we detail who gains and who loses from peer pressure, and identify some circumstances under which pressure results in fully (Pareto) optimal outcomes as well as circumstances where it does not. We also point out differences between positive and negative pressure. (JEL: Z13, D62, C72, D85)     

Bayesian inference for partially observed stochastic epidemics

The analysis of infectious disease data is usually complicated by the fact that real life epidemics are only partially observed. In particular, data concerning the process of infection are seldom available. Consequently, standard statistical techniques can become too complicated to implement effectively. In this paper Markov chain Monte Carlo methods are used to make inferences about the missing data as well as the unknown parameters of interest in a Bayesian framework. The methods are applied to real life data from disease outbreaks.     

Incorporating Ethnographic Methods in Multidisciplinary Approaches to Risk Assessment and Communication: Cultural and Religious Uses of Mercury in Latino and Caribbean Communities

The potential risk from cultural and religious practices involving mercury in Latino and Caribbean communities raises central methodological and ethical questions for risk assessment and risk communication. Here, specific cultural practices unfamiliar to most risk professionals carry significant inherent risks in the eyes of those professionals but not necessarily in the eyes of practitioners. Practitioners' past experience and history as targets of religious suppression and anti-immigrant sentiment create a reluctance to engage with researchers or public health officials in risk assessment or preventive risk communication efforts. The potential for the risk--in this case mercury contamination in dwellings--to extend beyond the practicing community to future occupants adds to public health concern. Understanding the risks of these practices requires both an understanding of the cultural and political context, beliefs, and behaviors of mercury users and an understanding of the fate and transport of mercury in typical use scenarios. In this study, we employed ethnographic methods (interviews and participant observation) to understand beliefs and behavior about mercury use as well as quantitative modeling and measurement to estimate and assess potential exposures. This represents a new methodology tailored to situations in which traditional activities or observances that are integral components of cultural identity pose risks in and of themselves. Our findings indicate that there are different types of mercury use stemming from different cultural and religious traditions that result in different levels of exposure. Many of the mercury uses that can result in the highest exposures to mercury vapors have previously been attributed to the religious tradition of Santeria, but appear instead to have their roots outside of the religion.     

Updating Schemes, Correlation Structure, Blocking and Parameterization for the Gibbs Sampler

In this paper many convergence issues concerning the implementation of the Gibbs sampler are investigated. Exact computable rates of convergence for Gaussian target distributions are obtained. Different random and non-random updating strategies and blocking combinations are compared using the rates. The effect of dimensionality and correlation structure on the convergence rates are studied. Some examples are considered to demonstrate the results. For a Gaussian image analysis problem several updating strategies are described and compared. For problems in Bayesian linear models several possible parameterizations are analysed in terms of their convergence rates characterizing the optimal choice.