The causal relationship between female labor supply and fertility in the USA: updated evidence via a time series multi-horizon approach

The purpose of this paper is to investigate the causality between female labor supply and fertility in the presence of auxiliary variables such as education, female wages, and male relative cohort size. We employ annual time series data spanning the period 1948 to 2007 for both an aggregate and an age-specific group. Our econometric specification follows closely the concepts and procedures proposed by Dufour and Renault (Econometrica 66(5):1099–1125, 1998) and Dufour et al. (J Econom 132:337–362, 2006) in that we conduct multi-horizon causality tests that allow for direct and indirect effects to take place. The sign and economic importance of our results is assessed via the estimation of impulse response functions. Our results establish bidirectional indirect causality between female labor supply and fertility and suggest interesting causal chains among the system variables. Causality effects are stronger for the age-specific group.     

Gonadal steroids and visuo-spatial abilities in adult males: Implications for generalized age-related cognitive decline

The relationship between the gonadal steroids, testosterone and estrogen, and individual and group differences in performance on some cognitive tasks remains unclear but sex differences favoring males on some tests of visuo-spatial ability are large and robust. This aim of this review is to assess evidence for both organizational and activational effects of gonadal steroids as the principle cause of sex difference in visuo-spatial ability. Additionally, the implications of this relationship are discussed in the context of decreasing levels of gonadal steroids in aging males and psychological theories of generalized age-related cognitive decline. Based upon human and non-human research gonadal steroids have organizational effects on visuo-spatial ability in adulthood. Activational effects of gonadal steroids on visuo-spatial ability appear most dominant in older men and are necessary for maintaining optimal visuo-spatial ability; randomized clinical trials show that testosterone supplementation improves performance. Additionally, decreasing gonadal steroid levels in aging males may contribute to generalized age-related cognitive decline. Future supplementation studies in men should attempt to control for constituent abilities related to visuo-spatial task performance, and investigate interactions between dosage levels and baseline gonadal status. Further future animal research is required to investigate changes in gonadal steroid levels and their relationship to neurotransmitter systems, neural plasticity, and behavioral correlates.     

A reply to Donna Andrew

David M. Gordon, Richard Edwards and Michael Reich, Segmented Work, Divided Workers: The Historical Transformation of Labor in the United States (1982), xii + 288 (Cambridge University Press, Cambridge, £20.00, Paperback £6.95).

Craig R. Littler, The Development of the Labour Process in Capitalist Societies (1982), x + 226 (Heinemann Educational Books £14.50, paperback £6.50).

Charles F. Sabel, Work and Politics: The Division of Labor in Industry (1982), xiii + 304 (Cambridge University Press, Cambridge, £17.50).     

3D Collaborative Virtual Environments: Exploring the Link between Collaborative Behaviors and Team Performance

Increasingly, organizational work is conducted by virtual teams interacting across boundaries of space and time. Despite advances in collaborative technologies, members of virtual teams often find the experience challenging and a far cry from physically “being there.” In response, immersive and interactive three‐dimensional collaborative virtual environments (3D CVEs) are emerging and purported to address the shortcoming of earlier technologies. How teams will interact and ultimately perform in a 3D environment remains to be seen. In this study, drawing from group and communication theories, we explore the link between collaborative behaviors and the performance of virtual teams working in a 3D CVE. We report on the results of a controlled experiment consisting of 39 virtual teams of 91 individuals. Through cluster analysis, we identify distinct patterns of collaborative behaviors associated with differential levels of performance. Our findings provide a deeper understanding of how the unique spatial and visual characteristics of 3D CVEs may transform virtual work.     

Service Delivery and Civic Engagement: Disability Organizations in Northern Ireland

In the United Kingdom, the New Labour administration that came to power in 1997 has promoted two models of partnership between the state and the voluntary sector. The civic engagement model is based on the renewed interest among governments in the potential of voluntary organizations to contribute to the civic engagement of citizens. In the service delivery model, voluntary organizations are recruited to the task of delivering core social services. Drawing on data from disability-related voluntary organizations in Northern Ireland, this paper illustrates the impact of the service delivery partnership model on the development of voluntary action in the welfare field, and the relative paucity of resources allocated to participatory voluntary action and civic engagement. The consequent impact on the development of partnerships between the state and the voluntary sector is discussed.     

An ecological risk assessment for chlorpyrifos in an agriculturally dominated tributary of the San Joaquin River.

Single-species toxicity testing of ambient water samples and national-scale probabilistic risk assessment have implicated the organophosphorous (OP) insecticide chlorpyrifos (O, O-diethyl O-(3,5,6-trichloro-2-pyridyl)-phosphorothioate) as a potential chemical stressor of aquatic organisms residing in the lower San Joaquin River basin. This site-specific aquatic ecological risk assessment was conducted to determine the probability of adverse effects occurring from exposure to chlorpyrifos in an agriculturally dominated tributary of the San Joaquin River and to assess the ecological significance of such effects. Assessment endpoints were fish population persistence and invertebrate community productivity. Daily chemical measurements collected over a period of one year were analyzed temporally for frequency, duration, and spacing between events for acute and chronic exposure episodes. Effects thresholds for fish and freshwater lotic invertebrates were determined from single-species laboratory toxicity tests. Potential risk was characterized by the degree of overlap of distributions of exposure events and effects, with consideration given to additive toxicity of other OP insecticides, recovery periods, and duration of chronic exposure (> or = 21 d). Ecological significance was determined by analysis of fish assemblage dietary and reproductive habits in relation to the surrogate invertebrate taxa judged at risk. Results of analysis indicated no direct effects on fish, and indirect effects on fish through elimination of invertebrate food items were considered unlikely. Biological survey information will be necessary to address uncertainty in this risk conclusion, especially as it relates to the benthic invertebrate community. Results of this site-specific risk analysis suggest that fish population persistence and invertebrate community productivity were not adversely affected by measured chlorpyrifos residues during a year-long monitoring period.     

Is Rural Residency a Risk Factor for Childhood Poverty?1

Abstract The influence of rural variables on young children's poverty status, adjusting for individual and family characteristics, is explored. The literature suggests that specific demographic variables exert an overwhelming influence on children's poverty status. This is confirmed with data from the National Longitudinal Survey of Youth. Results also suggest that the residential histories of children have consequences for their poverty status, even after the influence of control variables has been taken into account. The conclusion identifies the integration of survey and ecological data as one promising direction for future research on childhood poverty.