Model-based clustering with sparse covariance matrices

Statistics and Computing - Finite Gaussian mixture models are widely used for model-based clustering of continuous data. Nevertheless, since the number of model parameters scales quadratically with...     

SODA WARS: THE EFFECT OF A SODA TAX ELECTION ON UNIVERSITY BEVERAGE SALES

We examine how soda sales changed due to the campaign attention and election outcome of a local excise tax on sugar‐sweetened beverages. Using panel data of beverage sales from university retailers in Berkeley, California, we estimate that soda purchases relative to control beverages significantly dropped immediately after the election, months before the tax was implemented in the city of Berkeley or on campus. Supplemental scanner data from off‐campus retailers reveal this result is not unique to the university setting. Our findings suggest soda tax media coverage and election outcomes can have larger effects on purchasing behavior than the tax itself. (JEL D12, H20, C23, I38, Q18)     

A Literature Review of Organizational Behavior Management Interventions in Human Service Settings from 1990 to 2016

We reviewed the Journal of Applied Behavior Analysis (JABA), Journal of Organizational Behavior Management (JOBM), and Behavior Analysis in Practice (BAP) from 1990 to 2016, to identify articles that evaluated organizational behavior management interventions in a human service setting. Of those articles, 75 articles met the inclusion criteria for the review, 44 from JABA (1990 to 2016), 22 from JOBM (1990 to 2016), and 7 from BAP (2008 to 2016). We categorized each selected article by setting, employee population, client population, assessment, dependent variable, independent variable, and outcome measures. Results from the review are discussed for all three journals. Recommendations are made to broaden the scope of population and dependent variable targets, include more assessments, and include outcome data when applicable.     

Implicit Valuation of the Near-Miss is Dependent on Outcome Context

Gambling studies have described a “near-miss effect” wherein the experience of almost winning increases gambling persistence. The near-miss has been proposed to inflate the value of preceding actions through its perceptual similarity to wins. We demonstrate here, however, that it acts as a conditioned stimulus to positively or negatively influence valuation, dependent on reward expectation and cognitive engagement. When subjects are asked to choose between two simulated slot machines, near-misses increase valuation of machines with a low payout rate, whereas they decrease valuation of high payout machines. This contextual effect impairs decisions and persists regardless of manipulations to outcome feedback or financial incentive provided for good performance. It is consistent with proposals that near-misses cause frustration when wins are expected, and we propose that it increases choice stochasticity and overrides avoidance of low-valued options. Intriguingly, the near-miss effect disappears when subjects are required to explicitly value machines by placing bets, rather than choosing between them. We propose that this task increases cognitive engagement and recruits participation of brain regions involved in cognitive processing, causing inhibition of otherwise dominant systems of decision-making. Our results reveal that only implicit, rather than explicit strategies of decision-making are affected by near-misses, and that the brain can fluidly shift between these strategies according to task demands.     

What shapes plant and animal diversity on urban golf courses?

Recent concern over increasing loss of biodiversity has prompted considerable interest in the role of urban green spaces as reservoirs of local biodiversity. This study assessed the diversity of three indicator taxa - plants, ants and birds - on golf courses spanning a wide range of environmental variation in terms of climate, elevation, course age, size and connectivity to native woodland. Species richness and community composition was further compared between contrasting on-course habitat types that reflect different management intensities. We identified a set of taxon-specific environmental correlates indicating an intricate interplay of landscape- and local-scale variables that affect local species diversity. Our results show that floristic diversity is positively associated with the amount of rainfall, whereas ant and bird diversity are related to local-scale factors, particularly the number of trees and the size of water features on a site. The amount of on-course native habitat was a strong predictor of plant and ant diversity and was also associated with the number of unique species at the site level; this reinforces the value of remnant habitat patches as local biodiversity reservoirs that represent mini hot-spots in an otherwise species-poor urban landscape. Community composition for all three taxa differed markedly between non-playing and playing areas, with boundary and remnant habitats generally having more diverse, species-rich communities. Our results suggest that local floral and faunal biodiversity on urban golf courses can be enhanced by creating woody non-playing areas and, especially, by preserving, restoring or expanding remnant habitats.     

Family support in practice: voices from the field

This paper revisits core family support messages for social work practice in working with children and families, linking to findings from high-profile child protection cases in the UK and the Republic of Ireland. Drawing on a comparative study where these identified practice messages were explored through the lens of testimony of family support workers in the UK and Ireland, these core messages are examined. Operating with hard-to-engage children and parents, we hear how families and family support worker colleagues now view the core functions of child and family work across both jurisdictions (Ireland and England). The authors argue that by naming a more detailed set of practices that are deemed as most useful by families, based on the benefits and challenges of intensive family support work, key messages arise that have major resonance for social work and multiagency practice into the future. A basic message from this study is that valuable lessons on engagement and intervention with families can be drawn for professionals by examining the practice elements of this group of paraprofessionals in the child and family arena. This paper adds to debates on the role of support and intervention in social work and family support work.     

Walking Ability is Associated with Social Communication Skills in Infants at High Risk for Autism Spectrum Disorder

Achievement of early motor milestones in infancy affords new opportunities for social interaction and communication. Research has shown that both motor and social deficits are observed in infants who later develop autism spectrum disorder (ASD). This study examined associations between motor and Social communication skills in 12‐month‐old infant siblings of children with ASD who are at heightened risk for developmental delays (N = 86) and low‐risk, typically developing infants (N = 113). Infants were classified into one of three groups based on their walking ability: walkers (walks independently), standers (stands independently), or prewalkers (does not yet stand or walk independently). Social communication and cognitive skills were assessed with two standardized assessments (Communication and Symbolic Behaviors Scales [CSBS] and Mullen Scales of Early Learning) and compared across the three walking groups. Results demonstrated that high‐risk walkers showed superior Social communication skills, but commensurate cognitive skills, compared to high‐risk prewalkers. In contrast, Social communication and cognitive skills were largely comparable for low‐risk infants, regardless of walking status. Findings suggest that for high‐risk infants, who are already vulnerable to developmental delays and ASD, independent walking may facilitate the emergence of Social communication abilities. Pivotal motor milestones may serve as useful indicators of Social communication delays and targets for intervention.     

Defending the Family,Defending the Faith: An Analysis of The Family: A Proclamation to the World,Religious Identity,and the Politics of Same-Sex Marriage in a Mormon Community

In this article, we apply Peter Berger's theory of religion as a social construct to learn how The Church of Jesus Christ of Latter-day Saints (the Mormon Church) advances a heteronormative view of family relationships in the United States using a document titled The Family: A Proclamation to the World. Furthermore, applying cultural studies theory, we examine how believing Mormons negotiate the tension that arises when their secular values compete with those expressed by Church leaders. We argue that, although the Proclamation addresses a number of issues, the Church offers a closed text that emphasizes war narratives in which same-sex marriage is portrayed as a threat to LDS identity and the heteronormative family. This closed text is further legitimized by emphasis on the authority of Church leaders as oracles of God. The study participants largely accept the dominant narrative, and those who reject it, do so with some trepidation.     

Unemployment,Reemployment, and Health Insurance Status Among Older Workers in the Flexible Labor Market

As employment becomes more precarious, and spells of displacement become more common across the labor market, many individuals are forced to make decisions about the speed at which they seek reemployment and the types of employment they will seek. Using repeated cross‐sectional data from various years of the Displaced Worker Supplement of the Current Population Survey, we examine the degree to which employer‐provided health insurance and organizational provision of advanced layoff warning helped workers—particularly those from earlier birth cohorts—navigate the labor market during a period of growing employment flexibility. Our results indicate that workers from older cohorts, rather than older chronological ages, suffered more from displacement in terms of longer unemployment spells and declines in job quality upon reemployment. Workers able to obtain a job with health insurance had shorter unemployment durations, while those displaced from jobs with health insurance remained unemployed for longer periods of time. Advance notice appears to reduce some of the disproportionately negative effects of displacement for older workers, perhaps by easing the shock of a psychological contract breach. Our findings point to the importance of historical and cultural factors in shaping labor market outcomes.