Bayesian analysis of mixture modelling using the multivariate t distribution

A finite mixture model using the multivariate t distribution has been shown as a robust extension of normal mixtures. In this paper, we present a Bayesian approach for inference about parameters of t-mixture models. The specifications of prior distributions are weakly informative to avoid causing nonintegrable posterior distributions. We present two efficient EM-type algorithms for computing the joint posterior mode with the observed data and an incomplete future vector as the sample. Markov chain Monte Carlo sampling schemes are also developed to obtain the target posterior distribution of parameters. The advantages of Bayesian approach over the maximum likelihood method are demonstrated via a set of real data.     

Policing “Domestic Disturbances” in Small Towns and Rural Communities: Implications for Officer and Victim Safety

Drawing on Canadian police data on homicide involving domestic dispute calls from 1960 to the present (n = 20), as well as on in‐depth interviews with police officers (n = 33) working in rural and remote communities, the authors reexamine the argument that police attendance at domestic disturbance calls can pose a special threat to officer safety. Although some scholarship suggests that purported risks have been overstated, the authors argue that location may be a critical factor in reducing or heightening not only risks to officers, but also to victims. Although intended as an exploratory work, situated within the context of cultural support for domestic violence in rural communities, the authors raise both interesting policy implications, as well as potential avenues for future research. En partant de données de la police canadienne sur les homicides impliquant des disputes familiales de 1960 à nos jours (n = 20), ainsi que sur des entrevues en profondeur avec des agents policiers (n = 33) travaillant dans des régions rurales et des communautés éloignées, les auteurs ré‐examinent l'argument voulant que les interventions policières lors d'appels liés à des problèmes domestiques posent un risque spécial pour les agents policiers. Même si certains spécialistes suggèrent que ces risques sont exagérés, les auteurs affirment que le lieu pourrait être un facteur important par rapport au niveau de risque pour les agents policiers, ainsi que les victimes. Même s'il s'agit d'une recherche exploratoire, se situant dans le contexte du soutient culturel de la violence domestique dans les communautés rurales, les auteurs s'intéressent à la fois aux implications en termes de gestion et aux directions possibles en termes de recherches futures.     

'You've gotta learn how to play the game': homeless women's use of gender performance as a tool for preventing victimization

As a masculinist space, ‘the streets’ present a variety of dangers to homeless women, a fact that has received too little attention within the social science literature. This study utilizes data drawn from interviews with homeless women and service providers in Edinburgh, San Francisco, Vancouver, Montreal and Ottawa, to explore the complex survival strategies that homeless women develop to prevent criminal victimization. Through women's words, we see that gender is understood strategically as performance. Four gender performances are identified and discussed: the ‘femininity simulacrum’, the ‘masculinity simulacrum’, ‘genderlessness’ and ‘passing’. We discussed how each of these performances is employed in the pursuit of safety and security in frequently violent and chaotic social spaces.     

Black Mayors/White Mayors: Explaining Their Approval

Performance models have been the norm in research on nationaland state executives, but oddly this model has rarely been extendedto the next level of executive office, mayors. The increasingnumber of African American mayors suggests that race may complicatethe performance model of approval at the local level. This researchtests a performance model of mayoral approval that takes racialfactors into account. The model is tested in two white citieswith white mayors and two black cities with black mayors. Performanceis measured by citizen evaluations of a variety of urban conditions,some of which citizens can observe firsthand. Findings indicatethat (1) performance matters in evaluating black and white mayors,and its influence does not seem to be related to the race ofthe mayor; (2) performance has more explanatory power over mayoralapproval than race, a pattern that holds for both black andwhite mayors; (3) race has more impact on the approval of blackmayors than on white mayors; and (4) blacks in black citieshave lower evaluations of local government performance in theircities than blacks in white cities. We conclude that the performancemodel is generalizable to the local level, even with the complicationsof race.     

Importance-Performance Matrix Analysis of the Researcher’s Competence in the Formation of University-Industry Collaboration Using Smart PLS

This study empirically identified and investigated the importance and performance of researcher’s competence which serves as crucial stimuli in initiating university-industry collaborative activities in Malaysian research universities using Importance-Performance Matrix Analysis (IPMA). The findings are endorsed by the IPMA that the importance and performance of domain knowledge are high in contributing to sustainability entrepreneurship thus lead to the university-industry collaboration formation. It is also found that social capital and market knowledge are important but the performance of these areas required attention from the management to further enhance. Unexpectedly, it is suggested that the management should pay less attention to researcher reputation as this is the least priority area for improvement as demonstrated by the results generated by the IPMA. Essentially, the findings contribute to the benefit of the university leaders to understand the diversity of competence possessed by the academic researchers as valuable resources in spotting and seizing a business opportunity.

     

A National Survey of Child Advocacy Center Directors Regarding Knowledge of Assessment,Treatment Referral,and Training Needs in Physical and Sexual Abuse

Mental health services are a core component of child advocacy centers in the United States. Child advocacy center directors were surveyed about (a) trauma and posttraumatic stress disorder; (b) referral criteria for treatment of abuse victims; (c) evidence-based treatments for abused children; (d) reliable, valid, and normed measures helpful in assessment; and (e) training needs. Directors accurately identified posttraumatic stress disorder symptoms, but additional symptoms were misidentified. Directors identified best practices for assessment and treatment, but they misidentified non-evidence-based practices. Primary reasons for referral for services included severity of abuse and emotional response of the child. However, referrals based on assessment findings were not a high priority. Directors expressed some training needs for staff consistent with issues identified in the study.     

Less tangible ways of reading

Using the Internet, people realize the identity of their offline selves alongside establishing the nature of online simulacra, screen content. Drawing on European philosophy, responding to Asian audiences, the authors argue here for a theory of these processes as seriously ludic (or 'ludenic'). Asserting the 'primacy of play' in human-computer interaction (HCI), 'epistemological Calvinism' (Stone 1995, p. 9) is critiqued. Internet users' plural personalities switch between enabling roles in mundane material and mediated virtual worlds: they alternate aspects of the self, with the hermeneutic goal of constructing from hypertext menus online narratives of the read and hence (explicitly or implicitly) of the reader. The authors' hypothetical account of multicultural media appropriation as fundamentally (if not entirely) ludic is tested against the recorded evidence of Chinese and Malays talking in Malaysian focus groups about their experience of reading three online versions of newspapers. The virtual journalism accessed here was located on websites for the Australian (Melbourne) Age, UK (London) Times, and US (New York) Times. The Internet genre of e-journalism provides its readers with ludic gratification. Engaging with online news narratives can be an enjoyable escape from the daily round. Dutiful Internet use with a worldly purpose is more constrained in its capacity to liberate. As instrumental (with an extrinsic goal), it is therefore less than entirely playful but more materially functional. Nevertheless, the authors seek to show that such obligatory activity on the Web remains liminally ludic.     

False security or greater social inclusion? Exploring perceptions of CCTV use in public and private spaces accessed by the homeless

It has been well documented that owing to the vulnerability inherent in their situation and status, the homeless experience high rates of harassment and criminal victimization. And yet, the question of whether CCTV surveillance of public and private spaces – so frequently viewed by the middle classes as a positive source of potential security – might also be viewed by the homeless in similar ways. Within the present paper, I address this issue by considering the possibility that CCTV might be seen by some homeless men and women as offering: a) a measure of enhanced security for those living in the streets and in shelters, and; b) to the extent that security is conceived of as a social good, the receipt of which marks one as a citizen of the state, a means by which they can be reconstituted as something more than ‘lesser citizens’. To test these ideas, I rely on data from interviews conducted with homeless service users, service providers for the homeless, and police personnel in three cities. What is revealed is a mixed set of beliefs as to the relative security and meaning of CCTV.