Demand for gambling: development and assessment of a gambling purchase task

Self-report purchase tasks are a novel approach examining the reinforcing value of addictive behaviour relative to increasing monetary costs required to access the addictive behaviour (i.e. demand). These measures reveal a positive relationship between the indices of demand and addiction problem severity and can elucidate factors associated with motivation for substance use. Gambling is an addictive behaviour that has not been examined using this paradigm. This study seeks to adapt and examine the purchase task for gambling behaviour. A gambling purchase task was devised that asked individuals how often per month they would gamble at various cover charges. Participants were 73 adults from the community with either gambling disorder (n = 28) or alcohol use disorder (n = 24) or were a healthy control (n = 21). Both the alcohol and gambling purchase tasks were administered. Results demonstrate discriminant validity of the gambling purchase task, as individuals with gambling disorder have significantly greater demand for accessing gambling than other groups. The alcohol purchase task also evidenced discriminant validity in that individuals with alcohol use disorder have significantly greater demand for alcohol than other groups. These findings support the use of the gambling purchase task to assess the demand for gambling.     

Let Me Go: The Influences of Crawling Experience and Temperament on the Development of Anger Expression

Infants’ emerging ability to move independently by crawling is associated with changes in multiple domains, including an increase in expressions of anger in situations that block infants’ goals, but it is unknown whether increased anger is specifically because of experience with being able to move autonomously or simply related to age. To examine the influence of locomotion on developmental change in anger, infants’ (N = 20) anger expressions during an arm restraint procedure were observed longitudinally at a precrawling baseline assessment and 2 and 6 weeks after the onset of crawling. Infant age at each crawling stage was unrelated to the frequency of anger expressed in response to arm restraint. At 6 weeks postcrawling onset, infants whose mothers rated them as temperamentally higher in distress to limitations, compared with those rated lower, showed a greater increase in the frequency of anger expressed during the arm restraint relative to earlier assessments and took longer to reduce the frequency of anger expressed when no longer restrained. Findings suggest that experience with autonomous crawling has an effect on anger expression, independent of age, and that a temperamental tendency to become distressed by limitations may exacerbate the effect of crawling on anger expression.     

The Human Capital Characteristics and Household Living Standards of Returning International Migrants in Eastern and Southern Africa

Africa’s experience with return migration is not new. However, few empirical studies have examined the social and economic characteristics of returning migrants within the continent. In this study, the human capital endowments and household living standards of returning migrants in Uganda and South Africa are examined using recently available data. The study compares returnees in both countries with immigrants as well as the native‐born population with no international migration experience. It also investigates how factors such as previous country of residence, year of arrival, and other demographic factors predict levels of education and living standards among returning migrants. In Uganda, the results show that recently arrived returning migrants had better educational endowments than both immigrants and non‐migrants. Migrants who returned to Uganda following the fall of Idi Amin’s regime had the lowest educational levels and lowest living standards compared to other returnees. Furthermore, the results indicate that previous residence in countries in the West was associated with four additional years of schooling while returning migrants arriving from other African countries had the lowest levels of schooling among returning migrants. In South Africa, the study finds that returnees arriving almost immediately following the end of Apartheid had the highest levels of education compared to either immigrants or non‐migrants. Returnees on average also had the highest household living standards in South Africa. Among South African immigrants, the results indicate that those arriving towards the end of the century had lower educational endowments compared to immigrants who arrived in the country two to four years after the end of Apartheid.     

The Ethical Challenges of Socially Responsible Science

Social responsibility is an essential part of the responsible conduct of research that presents difficult ethical questions for scientists. Recognizing one’s social responsibilities as a scientist is an important first step toward exercising social responsibility, but it is only the beginning, since scientists may confront difficult value questions when deciding how to act responsibly. Ethical dilemmas related to socially responsible science fall into at least three basic categories: 1) dilemmas related to problem selection, 2) dilemmas related to publication and data sharing, and 3) dilemmas related to engaging society. In responding to these dilemmas, scientists must decide how to balance their social responsibilities against other professional commitments and how to avoid compromising their objectivity. In this article, we will examine the philosophical and ethical basis of social responsibility in science, discuss some of the ethical dilemmas related to exercising social responsibility, and make five recommendations to help scientists deal with these issues.     

Listening to the voices of children: understanding the human rights priorities of children with disability in Vanuatu and Papua New Guinea

In developing countries, children with disability lack basic services yet their voices are missing in the development agenda. This article reports on research to investigate the human rights needs and priorities of 89 children with disability aged 5–18 years in Vanuatu and Papua New Guinea. An accessible and inclusive research method was developed to enable children with diverse disabilities to communicate their own views via visual, audio and tactile means. Data were analysed in relation to the Articles of the Convention on the Rights of Persons with Disabilities, identifying a wide range of priority areas including recreation, leisure and cultural life; employment; home and family life; and education. It is proposed that policy and programme responses must take a holistic view of children and their needs, affirming but thinking beyond the importance of education, to address the complexity of the systemic disadvantage faced by children with disability.     

Stochastic metafrontiers

ABSTRACT

We consider the case of production units arranged into a number of groups. All units within a group choose output–input combinations from the same production possibilities set that is represented by a stochastic frontier model. The metafrontier is the envelope of the group-specific frontiers. We are interested in the metafrontier distance, which is the amount by which the group-specific frontier lies below the metafrontier.

Previous work has measured the metafrontier distance using the deterministic portion of the frontier. In a stochastic frontier model, this is not appropriate. We show how to evaluate the metafrontier distance, and we demonstrate the empirical relevance of this issue.     

Split Hamiltonian Monte Carlo

We show how the Hamiltonian Monte Carlo algorithm can sometimes be speeded up by “splitting” the Hamiltonian in a way that allows much of the movement around the state space to be done at low computational cost. One context where this is possible is when the log density of the distribution of interest (the potential energy function) can be written as the log of a Gaussian density, which is a quadratic function, plus a slowly-varying function. Hamiltonian dynamics for quadratic energy functions can be analytically solved. With the splitting technique, only the slowly-varying part of the energy needs to be handled numerically, and this can be done with a larger stepsize (and hence fewer steps) than would be necessary with a direct simulation of the dynamics. Another context where splitting helps is when the most important terms of the potential energy function and its gradient can be evaluated quickly, with only a slowly-varying part requiring costly computations. With splitting, the quick portion can be handled with a small stepsize, while the costly portion uses a larger stepsize. We show that both of these splitting approaches can reduce the computational cost of sampling from the posterior distribution for a logistic regression model, using either a Gaussian approximation centered on the posterior mode, or a Hamiltonian split into a term that depends on only a small number of critical cases, and another term that involves the larger number of cases whose influence on the posterior distribution is small.