Robust finite mixture modeling of multivariate unrestricted skew-normal generalized hyperbolic distributions

In this paper, we introduce an unrestricted skew-normal generalized hyperbolic (SUNGH) distribution for use in finite mixture modeling or clustering problems. The SUNGH is a broad class of flexible distributions that includes various other well-known asymmetric and symmetric families such as the scale mixtures of skew-normal, the skew-normal generalized hyperbolic and its corresponding symmetric versions. The class of distributions provides a much needed unified framework where the choice of the best fitting distribution can proceed quite naturally through either parameter estimation or by placing constraints on specific parameters and assessing through model choice criteria. The class has several desirable properties, including an analytically tractable density and ease of computation for simulation and estimation of parameters. We illustrate the flexibility of the proposed class of distributions in a mixture modeling context using a Bayesian framework and assess the performance using simulated and real data.

     

Iwi community justice panels reduce harm from re-offending

ABSTRACT

The effect of iwi community justice panels is assessed using data from seven years of implementation. Panel participants of 1013 are compared to a control group drawn from 73,000 offenders charged with similar offences and propensity-matched by age, gender, ethnicity, offending history and location. The dependent measure is re-harm from offending calculated using the NZ Crime Harm Index. Panel participants did not reduce their rate of offending compared to matched controls. However, there is a significant reduction in harm from post-panel offending, on average by 26.9 ± 21.05 equivalised prison days. The relative reduction is 22.25% of the harm committed by matched controls. Iwi panels are an effective alternative justice resolution. Panel participants are found to re-offend with minor offences and thus any focus on rates of offending would miss the complexity of the restorative justice process that reduces the harm of re-offending.     

Improving Gambling Survey Research Using Dual-Frame Sampling of Landline and Mobile Phone Numbers

Gambling prevalence studies are typically conducted within a single (landline) telephone sampling frame. This practice continues, despite emerging evidence that significant differences exist between landline and mobile (cell) phone only households. This study utilised a dual-frame (landline and mobile) telephone sampling methodology to cast light on the extent of differences across groups of respondents in respect to demographic, health, and gambling characteristics. A total of 2,014 participants from across Australian states and territories ranging in age from 18 to 96 years participated. Interviews were conducted using computer assisted telephone interviewing technology where 1,012 respondents from the landline sampling frame and 1,002 from the mobile phone sampling frame completed a questionnaire about gambling and other health behaviours. Responses across the landline sampling frame, the mobile phone sampling frame, and the subset of the mobile phone sampling frame that possessed a mobile phone only (MPO) were contrasted. The findings revealed that although respondents in the landline sample (62.7 %) did not significantly differ from respondents in the mobile phone sample (59.2 %) in gambling participation in the previous 12 months, they were significantly more likely to have gambled in the previous 12 months than the MPO sample (56.4 %). There were no significant differences in internet gambling participation over the previous 12 months in the landline sample (4.7 %), mobile phone sample (4.7 %) and the MPO sample (5.0 %). However, endorsement of lifetime problem gambling on the NODS-CLiP was significantly higher within the mobile sample (10.7 %) and the MPO sample (14.8 %) than the landline sample (6.6 %). Our research supports previous findings that reliance on a traditional landline telephone sampling approach effectively excludes distinct subgroups of the population from being represented in research findings. Consequently, we suggest that research best practice necessitates the use of a dual-frame sampling methodology. Despite inherent logistical and cost issues, this approach needs to become the norm in gambling survey research.     

Changes in risky gambling prevalence among a New Zealand population cohort

Evidence suggests that problem gambling is an unstable state where gamblers move into and out of risk over time. This article looks at longitudinal changes in risky gambling and the factors associated with an increased risk (measured by the Problem Gambling Severity Index [PGSI]) in the current New Zealand context, which has experienced a doubling of the electronic gaming machine (EGM) market over the last two decades. Respondents from a nationally representative baseline sample (n = 2672) were recontacted two years later to assess changes in gambling behaviours. Among the 901 respondents reached at follow-up, average gambling risk increased over time, and the prevalence of those who had at least some level of gambling risk (i.e. low-risk or greater) more than doubled (from 4.7% to 12.4%). The majority (80.2%) of those who were at risk at follow-up had not been at risk at baseline. Multivariate linear regression analyses show that the predictors of low to moderate increased risk include Pacific ethnicity; high neighbourhood deprivation status; baseline frequent, continuous gambler type; baseline PGSI status; and playing EGMs. These findings highlight the need to develop theories of gambling addiction trajectories and to identify the earliest point along the trajectory where public health interventions should occur.     

Disability and democracy in Cambodia: an integrative approach to community building and civic engagement

The political framework through which the various communities of disabled persons in Cambodia advocate for and claim their rights is complex and confusing. Both governmental and non‐governmental actors engage this political framework through the mobilization of persons from the various disabled communities, competing in the civic sphere through issue‐oriented advocacy in ways that seek to influence the process of democratic governance. While the status of disabled rights in Cambodia is still comparatively weak, it is argued here that this civic engagement has allowed disabled communities to find common cause with non‐disabled persons and groups in the project of deepening the roots of democracy in Cambodia. This article discusses the demographic composition of disability, the framework of political action that addresses disability issues and the practice of civic engagement and activism by disabled and non‐disabled communities in Cambodia.