Associations Between Morbidity and Alternative Measures of Particulate Matter

This paper explores the association between acute respiratory morbidity and different measures of exposure to airborne particulate matter, including sulfates, total suspended particulates, and fine and inhalable particulates. Regression analysis was used to test for the impacts of these alternative measures of particulate matter on respiratory morbidity using the 1979-1981 annual Health Interview Surveys and EPA's Inhalable Particle Monitoring Network. The general results indicate that, of the surrogate measures for particulate matter, sulfates appear to have the greatest association with morbidity. To the extent that sulfuric acid aerosols are correlated with airborne sulfates, the results suggest that respiratory impairment sufficient to lead to days of reduced activity may be related to the existence of acidity in the air. These findings are consistent with the results of ecological studies reporting an association between mortality and exposures to fine particles and sulfates.     

On the effect of the number of quadrature points in a logistic random effects model: an example

Although generalized linear mixed models are recognized to be of major practical importance, it is also known that they can be computationally demanding. The problem is the evaluation of the integral in calculating the marginalized likelihood. The straightforward method is based on the Gauss–Hermite technique, based on Gaussian quadrature points. Another approach is provided by the class of penalized quasi-likelihood methods. It is commonly believed that the Gauss–Hermite method works relatively well in simple situations but fails in more complicated structures. However, we present here a strikingly simple example of a logistic random-intercepts model in the context of a longitudinal clinical trial where the method gives valid results only for a high number of quadrature points ( Q ). As a consequence, this result warns the practitioner to examine routinely the dependence of the results on Q . The adaptive Gaussian quadrature, as implemented in the new SAS procedure NLMIXED, offered the solution to our problem. However, even the adaptive version of Gaussian quadrature needs careful handling to ensure convergence.     

Adolescents' and parents' affect in relation to discrepant perceptions of parental warmth in daily life

The current study aimed to evaluate how adolescents' and parents' perceptions of daily parenting—and their discrepancies—relate to daily parent and adolescent affect. Daily parental warmth and affect were assessed using electronic diaries in 150 American adolescent–parent dyads (61.3% females, M_age = 14.6, 83.3% White; 95.3% mothers, M_age = 43.4; 89.3% White) and in 80 Dutch adolescents with 79 mothers and 72 fathers (63.8% females, M_age = 15.9, 91.3% White; M_age = 49.0, 97.4% White). Results of preregistered models indicated that individuals' affect may be more important for perceptions of parenting than discrepancies between parent–adolescent reports of parenting for affect, stressing the need to be aware of this influence of affect on parenting reports in clinical and research settings.     

Incremental exercise tests in master athletes and untrained older adults

This study aimed to analyze the impact of step-duration protocols, 1-min vs. 3-min, on cardiorespiratory responses to exercise, whatever the aerobic-fitness level of sedentary (65.5 +/- 2.3 years, n = 8) or highly fit (63.1 +/- 3.2 years, n = 19) participants. Heart rate and VO2 at the first and second ventilatory thresholds (VT1 ,VT2) and maximal exercise were not significantly different between the two protocols. In master athletes, the 3-min protocol elicited significantly lower ventilation at VT2 and maximal exercise (p < .01). In the latter, breathlessness was also lower at maximal exercise (p < .05) than in sedentary participants. In trained or sedentary older adults, VT1, VT2, and were not influenced by stage duration. According to the lower breathlessness and ventilation, however, the 3-min step protocol could be more appropriate in master athletes. In untrained participants, because the cardiorespiratory responses were similar with the two incremental exercise tests, either of them could be used.     

Remittances in Ghana: Origin, Destination and Issues of Measurement

Few studies on remittances have focused on sub-Saharan Africa. This paper analyses a nationwide survey of 5,998 households to determine the characteristics of both internal and overseas remittances in Ghana. Particular attention is paid to the poverty-alleviation potential of remittances. Furthermore, this study uses a smaller scale pilot project with a matched sample of senders and receivers of remittances to identify some problems with using household-level surveys to assess the volume and impact of overseas remittances, and offers some suggestions as to how to handle these problems. The paper estimates that foreign remittances may be three times as large as Bank of Ghana estimates, bringing Ghana on par with large remittance receiving countries such as the Philippines and Mexico. The paper concludes that while foreign remittances are larger in value, locally sent remittances reach poorer segments of the population. Both foreign and local remittances are unevenly geographically distributed, being received more in the centre and southern regions than in northern Ghana where the poorest regions are. The paper argues a need to study multiplier effects of foreign remittances, as these can be large and eventually accrue to rural populations.     

Size and distribution trade-offs for the leximin ordering

A relative invariant and an absolute invariant inequality ordering satisfying extreme bottom-sensitivity, are proposed. It is shown that the leximin social welfare ordering can be expressed in terms of a ranking of distributions on the sole basis of their size, measured by the mean, and the degree of inequality, measured according to these inequality concepts. Leximin thus exhibits extreme bottom-sensitivity. This property does not withstand that leximin prefers a larger size of the cake at the cost of higher inequality in a number of cases. These trade-offs between size and equality are characterised in terms of degrees of dominance of the lower parts of the ordinary and absolute Lorenz curves that are accepted by leximin for a given increase in the mean.