Single,Cohabitating, and Married Mothers’ Time With Children

Utilizing the 2003 and 2004 American Time Use Survey (ATUS), this study examines the relationship between family structure and maternal time with children among 4,309 married mothers and 1,821 single mothers with children less than 13 years of age. Single mothers spend less time with their children than married mothers, though the differences are not large. Marital status and living arrangement differences in time with children largely disappear or single mothers engage in more child care than married mothers after controls for socioeconomic status and other characteristics are introduced. Thus, less maternal time with children appears to be mainly attributable to the disadvantaged social structural location of single mothers rather than different proclivities toward mothering between married and single mothers.     

America's children: mixed prospects

The prospects of US children are uneven and uncertain. Today's youngsters are more apt to have fewer siblings, come from a broken home, have a working mother, and pass time as a "latchkey kid." More children are in child care than in the past and there has been a significant move toward center-based care. Increasingly, preschool-age children, particularly from relatively well-off families, are enrolled in prekindergarten educational settings. Declining family size and recent American prosperity have created material well-being for most of today's children. But the development of an underclass has also increased the number of children trapped in poverty. The stagnant wages of the "working poor" and the growing number of mother-only households have exacerbated income inequality among children from different family circumstances. The decline in educational achievement scores, which characterized the 1970s, has, for the moment at least, ended and the average school performance even improved slightly in the 1980s. In addition, more students, especially black students, completed high school in the 1980s. And the physical health of the average American child has improved dramatically since 1960. Most American children lead happy, healthy lives and several trends portend well for the future of most youngsters. But the picture is marred by the problematic future of the children of the underclass and the uncertain psychological impact of America's transformed family life.     

Valuing Diversity and Interest in Intergroup Contact

The present research examines ways in which valuing diversity relates to interest in intergroup contact among members of minority and majority status groups. Using open-ended responses, Study 1 reveals that ethnic minority group members are less likely to perceive that diversity is valued than ethnic majority group members, yet those who perceive that diversity is valued tend to express greater interest in intergroup contact. Surveys of Black and White respondents (Study 2) and ethnic minority and majority respondents (Study 3) indicate similar trends. Moreover, these studies consistently show that valuing diversity uniquely predicts interest in intergroup contact among majority group members, whereas perceiving that outgroup members value diversity predicts interest in intergroup contact among minority group members. Implications of these findings for understanding the role of diversity in intergroup relations, and reformulating aspects of intergroup contact theory, are discussed.     

Power laws and fragility in flow networks

What makes economic and ecological networks so unlike other highly skewed networks in their tendency toward turbulence and collapse? Here, we explore the consequences of a defining feature of these networks: their nodes are tied together by flow. We show that flow networks tend to the power law degree distribution (PLDD) due to a self-reinforcing process involving position within the global network structure, and thus present the first random graph model for PLDDs that does not depend on a rich-get-richer function of nodal degree. We also show that in contrast to non-flow networks, PLDD flow networks are dramatically more vulnerable to catastrophic failure than non-PLDD flow networks, a finding with potential explanatory power in our age of resource- and financial-interdependence and turbulence.     

Cognitive and organizational ergonomics in the transition of the new integrated center of control of an oil refinery: human reliability and administration of changes

The conception of a product is closely tied to its adaptation level to the users. In this view, designers are increasingly oriented to survey the needs and features of the users. This paper aims at developing a diagnosis of employees working in high-complexity activities in a petrochemical company, in light of the physical and operating changes in the Integrated Center of Control; assessing the reception sensibility to changes; assessing the cognitive pattern of the group; and making suggestions that might eliminate or minimize the difficulties in the transition process of the change, in order to reduce the adaptation period. The field of study comprised 111 production, transfer and storage operators, forming 5 groups of desktop activities. The stages of the study followed the following flow: survey of the prescribed tasks and organizational structure; Concentrated Attention test; application of the Work and Disease Risks Inventory (ITRA, Portuguese acronym); and structured psychological interview. The ITRA results pointed to a serious cognitive cost (3.83) for all five groups, this being the largest intervention focus. The items: division of task contents (3.52), social professional relationships (2.93), quality of the physical environment (2.91), physical cost (3.24), emotional cost (2.71), freedom of expression (3.77), professional fulfillment (3.41); experience and suffering (2.75), lack of recognition (2.18) and physical injuries (2.07) were considered critical. Meanwhile, social damages (1.64) and psychological injuries (1.35) are bearable. As to the Concentrated Attention test, most workers registered average level. In the individual interviews, workers showed that larger involvement in the process of physical, organizational and operational change in the desktops and on field works was required, as well as the follow up of implementations, so as to reduce the adaptation process and prevent rework (furniture, equipment, noise, form of communication with the area and training for the changes). As a result of the findings handed to the management and returned to the workers, several actions were implemented on ergonomic non-conformities found in the analysis. It is possible to prove the importance of the insertion of cognitive and organizational ergonomics in the building projects of new facilities for high-complexity activities in petrochemical plants.     

DO IMMIGRANTS CAUSE CRIME?

We examine the empirical relationship between immigration and crime across Italian provinces during the period 1990–2003. Drawing on police administrative records, we first document that the size of the immigrant population is positively correlated with the incidence of property crimes and with the overall crime rate. Then, we use instrumental variables based on immigration toward destination countries other than Italy to identify the causal impact of exogenous changes in Italy’s immigrant population. According to these estimates, immigration increases only the incidence of robberies, while leaving unaffected all other types of crime. Since robberies represent a very minor fraction of all criminal offenses, the effect on the overall crime rate is not significantly different from zero.     

Nonresponse in the American Time Use Survey: Who Is Missing from the Data and How Much Does It Matter?

This article examines nonresponse in a large government survey,the American Time Use Survey (ATUS), which interviews personsin households previously interviewed in the Current PopulationSurvey. The response rate for the ATUS has been below 60 percentfor the first two years of its existence, raising questionsabout whether the results can be generalized to the target population.The article begins with an analysis of the types of nonresponseencountered in the ATUS. Noncontact accounts for roughly 60percent of ATUS nonresponse, with refusals accounting for roughly40 percent. We find little support for the hypothesis that busypeople are less likely to respond to the ATUS but find considerablesupport for the hypothesis that people who are weakly integratedinto their communities are less likely to respond, mostly becausethey are less likely to be contacted. When we compare aggregateestimates of time use calculated using the ATUS base weightswithout any adjustment for nonresponse, estimates calculatedusing the ATUS final weights with a nonresponse adjustment,and estimates calculated using weights that incorporate ourown nonresponse adjustment based on a propensity model, we findsome modest differences, but the three sets of estimates arebroadly similar. The article ends with suggestions for furtherresearch and analysis.