Modelling daily multivariate pollutant data at multiple sites

Summary. This paper considers the spatiotemporal modelling of four pollutants measured daily at eight monitoring sites in London over a 4-year period. Such multiple-pollutant data sets measured over time at multiple sites within a region of interest are typical. Here, the modelling was carried out to provide the exposure for a study investigating the health effects of air pollution. Alternative objectives include the design problem of the positioning of a new monitoring site, or for regulatory purposes to determine whether environmental standards are being met. In general, analyses are hampered by missing data due, for example, to a particular pollutant not being measured at a site, a monitor being inactive by design (e.g. a 6-day monitoring schedule) or because of an unreliable or faulty monitor. Data of this type are modelled here within a dynamic linear modelling framework, in which the dependences across time, space and pollutants are exploited. Throughout the approach is Bayesian, with implementation via Markov chain Monte Carlo sampling.     

The shape of mortality curves: an analysis of counties in England and Wales, 1911

Previous analysis has shown that life tables may be distinguished by two orthogonal pieces of information, the level of mortality in the population and the relative shape of the mortality curve. We show that both the regions of England and Wales in 1911, and locality types (county boroughs, other urban, and rural) differ in the shape of their mortality curves. Using data for the administrative counties, we examine the underlying correlates of this differentiation, paying particular attention to the socio-economic structure of the counties as reflected in their wealth, opportunity levels, and degree of urbanisation.     

Successful collaboration between the nonprofit and public sectors

Public and private funding sources often require nonprofit organizations to provide evidence of partnership with a governmental entity before financing a project. However, the circumstances under which working partnerships between the nonprofit and public sectors are forged and sustained have not been fully studied. This article presents the findings of a case study of land trusts and local governments and identifies conditions that foster successful collaboration. Social factors such as experience on the part of key personnel in working with the opposite entity and genuine affection for each other are more important than economic benefits. This suggests that a nonprofit agency interested in creating a viable partnership to improve a project should give careful consideration to assigning staff.     

Asthma Patients' Activities and Air Pollution: A Semiparametric Censored Regression Analysis

Asthma patients' health status may be especially sensitive to some types of air pollution, but the evidence on this is mixed. We explore the effects of ground-level ozone on asthma patient's activities, breaking apart the usual aggregated category of leisure into indoor and outdoor activities, and differentiating those by whether the activities were active or inactive. Applying the semiparametric censored estimation method we demonstrate that even though the period over which activities were observed was relatively low in ozone levels, there is a significant impact of ozone on a few activities. The (non-ozone) economic and demographic variables in the model play significant roles in explaining the allocation of time among seven activities, suggesting the suitability of the approach for other household decision-making contexts.     

The availability of personal and external coping resources: Thier impact on job stress and employee attitudes during organizational restructuring

This study examines the relationships among personal coping resources, social support, external coping resources, job stressors and job strains in a sample of 110 American Telephone and Telegraph employees undergoing a major organizational restructuring. The study expanded on a model suggested by Ashford (1988) by defining another category of coping resources that employees may draw upon to deal with the stressors and strains which occur during major organizational changes. External coping resources were defined as those which provided employees with a sense of 'vicarious control' in stressful situations. Results indicated that personal coping resources, social support and external coping resources had a direct effect upon job stressor and strain levels. No 'buffering' effect of these coplng resources was found. Hierarchical regression analyses indicated that external coping resources added to the prediction of job stressors and strains even when pertonal coping resources and social support were entered first into the prediction questions.     

The Effects of Diversity on Small Work Group Processes and Performance

Diversity is an increasingly important factor inorganizational life as organizations worldwide becomemore diverse in terms of the gender, race, ethnicity,age, national origin, and other personal characteristics of their members. The exact impact ofwithin-group diversity on small group processes andperformance is unclear. Sometimes the effect ofdiversity seems positive, at other times negative, andin other situations, there seems to be no effect at all.In this article, we suggest that these types of findingsmight be explained by using agroup-development model to examine theimpact of diversity on group processes and performance. Our modeluses concepts from Jackson et al.'s (1995), Milliken andMartins' (1996), and other models, as well as our ownconcepts, to show how diversity affects group development and performance. Among the conceptsincluded in the model are readily detectable personalattributes, underlying personal attributes, cognitiveparadigm dissimilarity, cognitive costs and rewards, diversity management skills, group behavioralintegration, and cognitive performance resources. In thepages that follow, we will explain each of thecomponents of the model and suggest specific hypotheses generated from the model.