Towards optimal scaling of metropolis-coupled Markov chain Monte Carlo

We consider optimal temperature spacings for Metropolis-coupled Markov chain Monte Carlo (MCMCMC) and Simulated Tempering algorithms. We prove that, under certain conditions, it is optimal (in terms of maximising the expected squared jumping distance) to space the temperatures so that the proportion of temperature swaps which are accepted is approximately 0.234. This generalises related work by physicists, and is consistent with previous work about optimal scaling of random-walk Metropolis algorithms.     

Racial and Ethnic Disparities in the Lifetime Prevalence of Homelessness in the United States

Homelessness in the United States is often examined using cross-sectional, point-in-time samples. Any experience of homelessness is a risk factor for adverse outcomes, so it is also useful to understand the incidence of homelessness over longer periods. We estimate the lifetime prevalence of homelessness among members of the Baby Boom cohort (n = 6,545) using the 2012 and 2014 waves of the Health and Retirement Study (HRS), a nationally representative survey of older Americans. Our analysis indicates that 6.2 % of respondents had a period of homelessness at some point in their lives. We also identify dramatic disparities in lifetime incidence of homelessness by racial and ethnic subgroups. Rates of homelessness were higher for non-Hispanic blacks (16.8 %) or Hispanics of any race (8.1 %) than for non-Hispanic whites (4.8 %; all differences significant with p < .05). The black-white gap, but not the Hispanic-white gap, remained significant after adjustment for covariates such as education, veteran status, and geographic region.     

Household Income,Women's Earnings,and Spending on Household Services, 1980–2010

The authors investigated changes in household outsourcing, the practice of spending on services that replace household labor, from 1980 to 2010. During this time, women's labor force participation, increased and economic, household bargaining, and time availability theories predict increased spending during this period. To test these predictions, the authors used data on spending on housekeeping, day care, babysitting and nannies, gardening and lawn services, eating out and pre‐prepared foods from the 1980–2010 Consumer Expenditure Surveys using 327,903 household‐quarters from the interview survey and 86,877 household‐weeks from the diary survey. The results indicate that changes in income predicted increases in housekeeping, child care, and gardening services. Changes in household characteristics predicted little change in food outsourcing, although food outsourcing did increase. Changes in women's earnings predicted little change in most outsourcing. The authors conclude the article with a discussion of the changing context for outsourcing.     

Identity,impairment and disablement: exploring the social processes impacting identity change in adults living with acquired neurological impairments

The social model of disability acknowledges the impact of impairments but argues that disablement is socially constructed. Taking a theoretical perspective, underpinned by the social model of disability and elements of social identity theory, we investigated the relationship between impairment, disablement and identity change in adults living with an acquired neurological impairment. Through the thematic analysis, three themes emerged: changing self described the personal factors for identity change in people acquiring impairment; changing communities explored the contextual factors creating both socially constructed disablement and identity change; and influencing identity change considered strategies adopted by individuals to both counter socially constructed disablement and promote exploration of identity. A systemic change towards acknowledgement and valuing a disabled identity may counter socially constructed disablement and support enablement and social inclusivity.     

I can hear the birds: using audio recordings to assess perceptions of amenity in urban riparian environments

Urban Ecosystems - The restorative qualities of nature (amenity values) have been explored for their benefits to human wellbeing. Yet methodology to assess restorative qualities is generally...     

A Latent Class Analysis of Gambling Activity Patterns in a Canadian University Sample of Emerging Adults: Socio-demographic,Motivational, and Mental Health Correlates

This analysis of gambling habits of Canadian university students (ages 18–25) dovetails two recent developments in the field of gambling studies. First, the popularity of latent class analysis to identify heterogeneous classes of gambling patterns in different populations; second, the validation of the Gambling Motives Questionnaire (with financial motives) among university students—specifically to understand both how and why emerging adults gamble. Our results support a four-class model of gambling activity patterns, consisting of female-preponderant casual and chance-based gambling groups, and male-preponderant skill-based and extensive gambling groups. Each class shows a specific combination of motives, underscoring the necessity for nuanced responses to problem gambling among emerging adults. More specifically, gambling for the skill-based group appears primarily to be a source of thrill and a way to cope; for the chance-based group, gambling appears but one symptom of a set of wider issues involving depression, anxiety, substance use, and low self-esteem; while extensive gamblers seem to seek excitement, sociality, and coping, in that order. Only the chance-based group was significantly more likely than casual gamblers to be motivated by financial reasons. Situating our analysis in the literature, we suggest that interventions for the predominantly male subtypes should address gambling directly (e.g. re-focusing excitement seeking into other activities, instilling more productive coping mechanisms) while interventions for predominantly female subtypes should address low self-esteem in conjunction with depression, substance abuse, and problematic levels of gambling. We conclude future research should focus on links between self-esteem, depression, substance abuse, and financial motives for gambling among female emerging adults.     

Co-development of Problem Gambling and Depression Symptoms in Emerging Adults: A Parallel-Process Latent Class Growth Model

This study examines whether there are multiple joint trajectories of depression and problem gambling co-development in a sample of emerging adults. Data were from the Manitoba Longitudinal Study of Young Adults (n = 679), which was collected in 4 waves across 5 years (age 18–20 at baseline). Parallel process latent class growth modeling was used to identified 5 joint trajectory classes: low decreasing gambling, low increasing depression (81%); low stable gambling, moderate decreasing depression (9%); low stable gambling, high decreasing depression (5%); low stable gambling, moderate stable depression (3%); moderate stable problem gambling, no depression (2%). There was no evidence of reciprocal growth in problem gambling and depression in any of the joint classes. Multinomial logistic regression analyses of baseline risk and protective factors found that only neuroticism, escape-avoidance coping, and perceived level of family social support were significant predictors of joint trajectory class membership. Consistent with the pathways model framework, we observed that individuals in the problem gambling only class were more likely using gambling as a stable way to cope with negative emotions. Similarly, high levels of neuroticism and low levels of family support were associated with increased odds of being in a class with moderate to high levels of depressive symptoms (but low gambling problems). The results suggest that interventions for problem gambling and/or depression need to focus on promoting more adaptive coping skills among more “at-risk” young adults, and such interventions should be tailored in relation to specific subtypes of comorbid mental illness.     

Gross primary productivity of a large metropolitan region in midsummer using high spatial resolution satellite imagery

Although gross primary productivity (GPP) is estimated with remote sensing over large regions of Earth, urban areas are usually excluded due to the lack of light use efficiency (LUE) parameters for urban vegetation and the spatial heterogeneity of urban land cover. Here, we estimated midsummer GPP, both within and among vegetation and land-use types, across the Minneapolis-Saint Paul, Minnesota metropolitan region. We derived LUE parameters for urban vegetation types using estimates of GPP from tree sap flow and eddy covariance CO₂ flux observations, and from fraction of absorbed photosynthetically active radiation based on 2 m resolution WorldView-2 satellite imagery. Mean GPP per unit land area (including vegetation, impervious surfaces, and soil) was 2.64 g C m^?2 d^?1, and was 4.45 g C m^?2 d^?1 per unit vegetated area. Mapped GPP estimates were within 11.4% of estimates from independent tall tower eddy covariance measurements. Turf grass GPP had a larger coefficient of variation (0.18) than other vegetation classes (~0.10). Vegetation composition was largely consistent across the study area. Excluding golf courses, mean land-use GPP for the total study area varied more by percent vegetation cover (R²?=?0.98, p?<?0.001) than by variability within vegetation classes (R²?=?0.21, p?=?0.19). Urban GPP in general was less than half that of natural forests and grasslands in the same climate zone.