Optimal representative sample weighting

Statistics and Computing - To overcome the inherent limitations of axis-aligned base learners in ensemble learning, several methods of rotating the feature space have been discussed in the...     

Influence of socioeconomic status on changes in body size and physical activity in ageing black South African women

Background

The increasing prevalence of obesity in sub-Saharan African women is not well understood, and black South African women in the region are particularly vulnerable. This study aimed to examine whether the relationship of socioeconomic status (SES) with changes in body mass index (BMI) and waist circumference (WC) is mediated by physical activity in ageing African women.

Methods

In a longitudinal analysis of the 518 caregivers associated with the Birth to Twenty Plus study, the role of SES associated with 10-year changes in BMI and WC was tested using structural equation modelling (SEM). The degree of mediation of moderate-vigorous physical activity (MVPA) and sitting time in this association was also assessed.

Results

The prevalence of obesity increased significantly from baseline to follow-up (p?<?0.0001). In the SEM models, baseline SES had a direct positive effect on changes in BMI (β, 95% CI, 0.02 (0.005 to 0.04), and a direct negative effect on changes in MVPA (β, 95% CI, ??3.81 (??6.92 to ??0.70). Baseline MVPA had a direct negative effect (β, 95% CI, ??0.002 (??0.003 to ??0.0003) and indirect positive effect via change in MVPA (β, 95% CI, 0.01 (0.0001 to 0.001) on change in WC.

Conclusions

Our study demonstrates the role and interaction of sociodemographic and behavioural predictors of obesity, and suggests a multifaceted approach to management of the crisis in communities of ageing urban African women.

     

The Impact of HIV Pre-exposure Prophylaxis (PrEP) Use on the Sexual Health of Men Who Have Sex with Men: A Qualitative Study in Seattle,WA

This study explores the impacts of HIV pre-exposure prophylaxis (PrEP) use on the sexual health of men who have sex with men (MSM). The authors conducted in-depth interviews with MSM who use PrEP (n = 14). Data was analyzed using interpretative phenomenological analysis. PrEP use reduced fear and shame associated with sex and facilitated greater sexual satisfaction and intimacy. Although participants generally viewed PrEP as empowering and beneficial, they also experienced PrEP-related stigma. The authors’ analysis emphasizes the importance of understanding the reasons MSM use PrEP and highlights opportunities for reducing harm and fostering sexual health among MSM who are using or considering PrEP.     

Older people and poverty in rural Britain: Material hardships,cultural denials and social inclusions

This paper explores the relations between older people, poverty and place in rural Britain. It develops previous work on rural poverty that has pointed both to the significance of older people within the rural poor population and to their denials of poverty. The paper also connects with recent discussions on the complexity of relations between poverty and social exclusion in later life, as well as key themes emerging from studies of older people in disadvantaged urban neighbourhoods. Drawing on findings from a survey of 4000 households in rural Wales and interviews with older people in poverty in three rural places, the paper provides a detailed examination of the materialities and experiences of poverty among older people in rural places. In particular, it highlights how older poor groups construct their lives in complex terms with references made to both social inclusions and exclusions. The research also points to the significance of the socio-cultural contexts of place in shaping older people's understandings of poverty in rural areas.     

Fathers’ Financial Support of Children in a Low Income Community in South Africa

We used data from the Birth to Twenty Cohort study to understand children’s receipt of financial support from their fathers in a low income, Black community in urban South Africa. Specifically, we (1) described fathers’ financial support over the life course of children; (2) estimated survival probabilities of receiving support for all children and not receiving support for children who experienced a parental union dissolution; and (3) identified factors that explained variation in the receipt of support after a union dissolution. Results suggest that most children received full or partial support throughout the life course. Furthermore, a high proportion of children received support after a union dissolution with much of the variation driven by pre-dissolution support, father’s education and the presence of extended kin.     

The Social Basis of Agro‐Environmental Concern: Physical versus Social Proximity

Abstract In this study, we explore the social basis of environmental concern, specifically focusing on attitudes about the agricultural environment in relation to an individual's geographic and social distance from agriculture. We also consider the significance of rural recreational behaviors in relation to agro‐environmental concern. The analysis, based on data from a statewide survey of Ohioans, reveals a strong relationship between one's geographic location along the rural‐urban continuum and attitudes about agriculture and the environment. This relationship, though, does not exist once the effects of social proximity to agriculture are accounted for, suggesting that the relationship between residential location along the rural‐urban continuum and agro‐environmental attitudes may be spurious. The analysis also reveals a strong relationship between participation in rural recreation and attitudes about agriculture and the environment. We describe several conceptual and practical implications of this research for natural‐resource management.     

A Cross‐Cultural Examination of the Disjuncture Between Aspirations and Expectations/Perceived Outcomes: Strain and Academic Deviance in the United States and Japan

Using comparable self‐reported survey data collected among college students in the United States (n = 502) and Japan (n = 441), this study examines a paradox of higher academic deviance among otherwise more conforming Japanese youth while revisiting the debate concerning the disjuncture between aspirations and expectations/perceived outcomes in Agnew's general strain theory (GST). Confirming the paradox, our results indicate that Japanese students are significantly more deviant academically than American students. However, contrary to the expectation of GST, but in support of past empirical studies, the higher academic deviance among the Japanese, as compared to Americans, is explained by their lower aspirations, irrespective of the levels of expectations/perceived outcomes     

A Taxometric Analysis of Problem Gambling Data from a South African National Urban Sample

We investigate the question whether problem gambling (PG) in a recent South African sample, as measured by the Problem Gambling Severity Index (PGSI), is dimensional or categorical. We use two taxometric procedures, Mean Above Minus Below A Cut (MAMBAC) and Maxim Covariance (MAXCOV), to investigate the taxonic structure of PG as constructed by the PGSI. Data are from the 2010 South African National Urban Prevalence Study of Gambling Behavior. A representative sample of the urban adult population in South Africa (N = 3,000). Responses are to the 9 item PGSI. MAMBAC provided positive but modest evidence that PG as measured by the PGSI was taxonic. MAXCOV pointed more strongly to the same conclusion. These analyses also provide evidence that a PGSI cutoff score of 10 rather than the standard 8 may be called for. PG as constructed by the PGSI may best be thought of as categorical, but further studies with more theory based measurements are needed to determine whether this holds in a wider range of samples and for other screens. A higher cutoff score may be called for on the PGSI when it is used for research purposes to avoid false positives.     

Women and Government Budgets

In recognition of the significant, but often unknown, impact of government budgets on the role and status of women, both Federal and State Labor government administrations have introduced ‘women's budget’ statements. It is important to recognise that the political motivation of governments in establishing women's budgets has been primarily political self interest. To some extent, however, the move also reflects the growing economic focus, and power, of the women's movement. This paper examines the content and limitations of women's budget programs.