A Bayesian finite mixture change-point model for assessing the risk of novice teenage drivers

The driving risk during the initial period after licensure for novice teenage drivers is typically the highest but decreases rapidly right after. The change-point of driving risk is a critical parameter for evaluating teenage driving risk, which also varies substantially among drivers. This paper presents latent class recurrent-event change-point models for detecting the change-points. The proposed model is applied to the Naturalist Teenage Driving Study, which continuously recorded the driving data of 42 novice teenage drivers for 18 months using advanced in-vehicle instrumentation. We propose a hierarchical BFMM to estimate the change-points by clusters of drivers with similar risk profiles. The model is based on a non-homogeneous Poisson process with piecewise-constant intensity functions. Latent variables which identify the membership of the subjects are used to detect potential clusters among subjects. Application to the Naturalistic Teenage Driving Study identifies three distinct clusters with change-points at 52.30, 108.99 and 150.20?hours of driving after first licensure, respectively. The overall intensity rate and the pattern of change also differ substantially among clusters. The results of this research provide more insight in teenagers' driving behaviour and will be critical to improve young drivers' safety education and parent management programs, as well as provide crucial reference for the GDL regulations to encourage safer driving.     

Information analysis of local suppression scheme based on a spatial-temporal model

In a wireless sensor network, data collection is relatively cheap whereas data transmission is relatively expensive. Thus, preserving battery life is critical. If the process of interest is sufficiently predictable, the suppression in transmission can be adopted to improve efficiency of sensor networks because the loss of information is not great. The prime interest lies in finding an inference-efficient way to support suppressed data collection application. In this paper, we present a suppression scheme for a multiple nodes setting with spatio-temporal processes, especially when process knowledge is insufficient. We also explore the impact of suppression schemes on the inference of the regional processes under various suppression levels. Finally, we formalize the hierarchical Bayesian model for these schemes.     

Competing and Cooperating Similarity in Global Strategic Alliances: An Exploratory Examination

We used two variables, competing similarity and cooperating similarity, in developing a comprehensive model that forces a simultaneous treatment of partner characteristics and partner capabilities in global strategic alliances. An empirical test of this model on a sample of 70 global strategic alliances indicated mixed support for our hypotheses, and suggested that competing similarity has a negative effect and cooperating similarity has a positive effect on alliance outcomes. Findings also show that deliberate 'relational efforts' mitigate the frictional effects of differences in partner characteristics.     

Priority Topics in the Study of Environmental Risk in Developing Countries: Report on a Workshop Held at the East–West Center, August, 1988

The rapid industrialization occurring in developing regions of the world brings not only economic benefits, but changes in the types and severity of health and environmental problems that each region experiences. As the industrialized world moves toward the use of risk assessment methodologies to aid in problem evaluation and regulatory and policy decision analysis, it seems inevitable that these methodologies will be applied globally. The changes brought about by rapid industrialization, however, must be viewed within the context of societies that are still struggling with the more traditional and basic environmental problems associated with urban and rural poverty. The urgency of development and the lack of adequate resources for characterizing health and environmental changes, often present under these circumstances, offer special challenges to the application of risk assessment methodologies.     

Citizens Advice Bureaux: Problems of an Emerging Service in Rural Areas

Nineteen eighty nine marked the Golden Jubilee of the CABx in the UK. Over the past 50 years it has established itself nationally as the prime provider of generalist advice, but there are special problems associated with delivering the service in rural areas. These include: the logistical difficulties of serving remote communities with small and scattered populations; maintaining the independence of bureau, especially from the local authorities that mainly fund them; and matching the professional standards now demanded by NACAB. These issues are examined with reference to a questionnaire survey of bureaux managers in Cornwall and Devon carried out as part of the AJRBP project at the University of Exeter.     

An application of attribution and equity theories to tax evasion behavior

Traditional economic theory often has been utilized in an attempt to explain tax evasion behavior. Although economic consequences are important factors in the understanding of tax evasion behavior, they alone do not appear adequate to describe and predict the phenomenon. The results of two experiments which apply two social psychological theories, attribution theory and equity theory, to tax evasion judgments are reported. In the first experiment, the effects of personal need and degree of societal consensus were investigated. Both variables significantly affected recommended penalty judgments. In the second experiment, the effects of societal need and distinctiveness were studied. Neither societal need nor distinctiveness affected recommended penalty judgments. However, a significant interaction effect was found concerning subjects' behavioral intentions to evade. The present research suggests that both attribution theory and equity theory may be helpful in formulating hypotheses and enhancing our understanding of tax evasion behavior.     

Acute stress reactions to everyday stressful life events among sexual abuse survivors with PTSD

This study examined symptoms of Acute Stress Disorder (ASD), which is often thought of as a precursor to PTSD, among 54 women who already had PTSD for childhood sexual abuse for which they were seeking treatment. We examined the prevalence of ASD symptoms as well as their relationships to trauma symptoms measured by the Trauma Symptom Checklist-40. The ASD diagnosis requires the occurrence of a traumatic life event as well as meeting specific symptoms criteria. We found that fourty-four percent of participants met all symptom criteria for ASD, but only three of these 24 participants described a traumatic life event. Moreover, ASD symptoms were significantly related to trauma symptom scores. These findings suggest that a significant proportion of women with PTSD for childhood sexual abuse may be highly symptomatic for everyday stressful events that would not be experienced as traumatizing to others. Thus, these individuals need assistance in coping with everyday life stressors that do not involve a serious threat or injury in addition to needing help to alleviate their trauma symptoms.     

When the rehabilitation ideal fails: a study of parental rights termination

This study explored the circumstances of parents whose extreme neglect and abuse of their young children justified the drastic state action of termination of their parental rights. Records of 97 children age 6 and under whose parental rights were terminated between 1991 and 1997 in Minnesota were reviewed. Profiles of parents and children were drawn from these data, and a "risk pool" of parents whose children became wards of the state was identified. Guidelines are drawn from this "risk pool" that may help alert practitioners to those parents who are unlikely to safely maintain their children. Questions and implications for policy and practice are highlighted.