Nest-site selection and nest depredation of semi-aquatic turtles on golf courses

Urban landscapes present various challenges to semi-aquatic turtle reproduction. In developed regions, golf courses may provide some of the best remaining habitat for turtle populations. We explored nest-site selection of eastern painted turtles (Chrysemys picta) at a golf course pond in Davidson, North Carolina, USA, and modeled nest-site preference using Akaike Information Criterion, with the best supported model favoring nests surrounded by mulch and mowed grass. Additionally, we evaluated nest depredation rates using simulated turtle nests and found that golf course ponds did not have significantly greater nest depredation compared to urban and rural ponds. Our results suggest that golf courses may offer suitable habitat for turtle reproduction in developed areas.     

The use of inter-marriage statistics as an index of assimilation

Marriage statistics have for many years been used as a means of assessing the speed with which immigrant, racial or ethnico-religious groups shed their ethnic identity and become assimilated. This paper reviews the problems involved in using marriage statistics for this purpose (making special reference to immigrant groups) and concludes that though inter-marriage is a reasonable measure of assimilation, the ratios in common use greatly overstate or distort the extent of inter-marriage. The paper then puts forward two much more reliable ratios— one measuring the tendency to inter-marry on the part of those having some opportunity to inter-marry, and the other measuring the actual extent of intermarriage in the ethnic group as a whole—and suggests that the best assessment comes from using these two in conjunction. Though these ratios are readily obtainable from field and documentary surveys they cannot be derived from official published statistics; the paper therefore puts forward another ratio which is obtainable from official statistics but is more reliable than the ratios in common use.     

Language Experience Shapes the Development of the Mutual Exclusivity Bias

Halberda (2003) demonstrated that 17‐month‐old infants, but not 14‐ or 16‐month‐olds, use a strategy known as mutual exclusivity (ME) to identify the meanings of new words. When 17‐month‐olds were presented with a novel word in an intermodal preferential looking task, they preferentially fixated a novel object over an object for which they already had a name. We explored whether the development of this word‐learning strategy is driven by children’s experience of hearing only one name for each referent in their environment by comparing the behavior of infants from monolingual and bilingual homes. Monolingual infants aged 17–22 months showed clear evidence of using an ME strategy, in that they preferentially fixated the novel object when they were asked to “look at the dax.” Bilingual infants of the same age and vocabulary size failed to show a similar pattern of behavior. We suggest that children who are raised with more than one language fail to develop an ME strategy in parallel with monolingual infants because development of the bias is a consequence of the monolingual child’s everyday experiences with words.     

Pornography and Marriage

We used data on 20,000 ever-married adults in the General Social Survey to examine the relationship between watching pornographic films and various measures of marital well-being. We found that adults who had watched an X-rated movie in the past year were more likely to be divorced, more likely to have had an extramarital affair, and less likely to report being happy with their marriage or happy overall. We also found that, for men, pornography use reduced the positive relationship between frequency of sex and happiness. Finally, we found that the negative relationship between pornography use and marital well-being has, if anything, grown stronger over time, during a period in which pornography has become both more explicit and more easily available.     

Exploring the economic and social determinants of psychological well-being and perceived social support in England

Summary.  A fundamental focus of Government concern is to enhance well-being. Recently, policy makers in the UK and elsewhere have recognized the importance of the community and society to the well-being of the nation as a whole. We explore the extent to which economic and social factors influence the psychological well-being of individuals and their perceptions of the social support that they receive, using Health Survey for England data. We employ a random-effects ordered probit modelling approach and find that unobserved intrahousehold characteristics help to explain the variation in our dependent variables, particularly for co-resident females. Our results indicate that individuals with acute and chronic physical illness, who are female, unemployed or inactive in the labour market and who live in poor households or areas of multiple deprivation report lower levels of psychological well-being. Reduced perceptions of social support are associated with being male, single or post marriage, from an ethnic minority, having low educational attainment and living in a poor household, but are not statistically related to area deprivation measures. These findings may help to inform the contemporary policy debate surrounding the promotion of individual well-being and community, through the alleviation of social exclusion.     

The English language fluency and occupational success of ethnic minority immigrant men living in English metropolitan areas

This paper examines two crucial aspects of the assimilation experience of ethnic minority immigrants in the United Kingdom. It explores the determinants of their English language (speaking) fluency and the key role such skills play in their occupational success. Our sample is derived from the Fourth National Survey of Ethnic Minorities undertaken in 1994. Uniquely this data contains an interviewer-assessed measure of English language fluency. Importantly, we also attempt to control for possible endogeneity bias in the estimates of the effect of language fluency on occupational success. We find that fluency is associated with significantly higher mean hourly occupational wages. Received: 26 November 1999/Accepted: 03 August 2000     

Covariate adjustment in partial least squares (PLS) regression for the extraction of the spatial–temporal pattern from positron emission tomography data

Positron emission tomography (PET) imaging can be used to study the effects of pharmacologic intervention on brain function. Partial least squares (PLS) regression is a standard tool that can be applied to characterize such effects throughout the brain volume and across time. We have extended the PLS regression methodology to adjust for covariate effects that may influence spatial and temporal aspects of the functional image data over the brain volume. The extension involves multi-dimensional latent variables, experimental design variables based upon sequential PET scanning, and covariates. An illustration is provided using a sequential PET data set acquired to study the effect of d-amphetamine on cerebral blood flow in baboons. An iterative algorithm is developed and implemented and validation results are provided through computer simulation studies.     

Women and plant closings: Unemployment,re-employment,and job training enrollment following dislocation

Major changes in the U.S. economy are leaving blue collar women vulnerable to extended unemployment, permanent job loss, or re-employment at lower wage and benefit levels. Consequently, retraining for other jobs may be a virtual necessity. Information about factors associated with women's employment status after job loss may be useful to policy makers and program planners providing assistance or training to dislocated women. This study of women workers, who are dislocated from jobs in textile and apparel plants in Georgia, identifies the differences between women who are unemployed, re-employed, or enrolled in job training programs following job loss. Findings suggest that stage of the family life cycle and the demands of combining production work and family responsibilities contribute to women's experience of unemployment and their labor market participation.