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191.
This paper considers quantile regression for a wide class of time series models including autoregressive and moving average (ARMA) models with asymmetric generalized autoregressive conditional heteroscedasticity errors. The classical mean‐variance models are reinterpreted as conditional location‐scale models so that the quantile regression method can be naturally geared into the considered models. The consistency and asymptotic normality of the quantile regression estimator is established in location‐scale time series models under mild conditions. In the application of this result to ARMA‐generalized autoregressive conditional heteroscedasticity models, more primitive conditions are deduced to obtain the asymptotic properties. For illustration, a simulation study and a real data analysis are provided.  相似文献   
192.
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.  相似文献   
193.
International and national biosecurity policies consider risk assessment a critical component of overall plant health risk analysis. The Agreement on the Application of Sanitary and Phytosanitary Measures, the International Plant Protection Convention, and the Convention on Biological Diversity all provide guidelines and recommendations on how to use risk assessment. This article discusses how these instruments address risk assessment, and makes recommendations on how the risk assessment process needs to incorporate current geospatial predictive science and geographic information systems into the plant health biosecurity risk analysis toolbox.  相似文献   
194.
Igor Linkov 《Risk analysis》2012,32(8):1349-1368
Recent severe storm experiences in the U.S. Gulf Coast illustrate the importance of an integrated approach to flood preparedness planning that harmonizes stakeholder and agency efforts. Risk management decisions that are informed by and address decision maker and stakeholder risk perceptions and behavior are essential for effective risk management policy. A literature review and two expert models/mental models studies were undertaken to identify areas of importance in the flood risk management process for layperson, non‐USACE‐expert, and two USACE‐expert groups. In characterizing and mapping stakeholder beliefs about risks in the literature onto current risk management practice, recommendations for accommodating and changing stakeholder perceptions of flood risks and their management are identified. Needs of the U.S. Army Corps of Engineers (USACE) flood preparedness and response program are discussed in the context of flood risk mental models.  相似文献   
195.
We propose a shift in emphasis when communicating to people when the objective is to motivate household disaster preparedness actions. This shift is to emphasize the communication of preparedness actions (what to do about risk) rather than risk itself. We have called this perspective “communicating actionable risk,” and it is grounded in diffusion of innovations and communication theories. A representative sample of households in the nation was analyzed using a path analytic framework. Preparedness information variables (including content, density, and observation), preparedness mediating variables (knowledge, perceived effectiveness, and milling), and preparedness actions taken were modeled. Clear results emerged that provide a strong basis for communicating actionable risk, and for the conclusion both that information observed (seeing preparedness actions that other have taken) and information received (receiving recommendations about what preparedness actions to take) play key, although different, roles in motivating preparedness actions among the people in our nation.  相似文献   
196.
This article examines a central plank of mental health policy (‘recovery’) in societies which have attempted to reverse the long-term warehousing of those with a diagnosis of mental disorder (de-institutionalisation). The emergence of the concept is traced in relation to the shift from an institutional to a more dispersed and community-based form of service organisation. Different usages of the term ‘recovery’, each with distinct implications for practice are considered on the part of three main interest groups (traditional bio-medical psychiatrists; social psychiatrists emphasising social skills training; and dissenting service users). These different usages suggest that ‘recovery’ is a polyvalent concept that creates an uneasy consensus point to define the management philosophies of local services enacting mental health policy. Also mental health work is about more than the group of patients mainly considered in relation to recovery (those with ‘severe and enduring mental health problems’). Practice-near research strategies are now required to investigate the varied practical scenarios these contradictions generate and ethnographic research is therefore indicated. Without multiple ethnographies, we will be left with competing rhetoric about recovery and its meaning or meanings may be rendered worthless.  相似文献   
197.
As part of a comprehensive environmental health strategic planning project initiated by the government of Abu Dhabi, we assessed potential dietary exposure in the United Arab Emirates (UAE) to methylmercury (in seafood) and pesticides (in fruits and vegetables) above international guideline levels. We present results for the UAE population by age, gender, and body mass index. Our results show very low daily risks of exposure to pesticides in fruits and vegetables at levels exceeding WHO guidelines even under the conservative assumption that no pesticides are removed during washing and food preparation. Thus, exposure to pesticides on fruits and vegetables does not appear to be a major public health concern in the UAE. The chances of exposure to methylmercury in seafood are much higher; our model estimates a mean 1 in 5 daily risk of exceeding the FAO/WHO provisional tolerable weekly intake. However, great caution should be used in interpreting these results, as we analyzed only the risks and not the substantial benefits of fish consumption. In fact, previous studies have demonstrated that exposure to the n‐3 polyunsaturated fatty acids in fish can increase IQ in developing children, and it can substantially decrease the risk in adults of coronary heart disease and stroke. Further research is warranted to compare the risk of Me‐Hg exposure from fish to the nutritional benefits of fish consumption in the UAE and to determine appropriate methods to communicate risk and benefit information to the UAE population.  相似文献   
198.
This article discusses how analyst's or expert's beliefs on the credibility and quality of models can be assessed and incorporated into the uncertainty assessment of an unknown of interest. The proposed methodology is a specialization of the Bayesian framework for the assessment of model uncertainty presented in an earlier paper. This formalism treats models as sources of information in assessing the uncertainty of an unknown, and it allows the use of predictions from multiple models as well as experimental validation data about the models’ performances. In this article, the methodology is extended to incorporate additional types of information about the model, namely, subjective information in terms of credibility of the model and its applicability when it is used outside its intended domain of application. An example in the context of fire risk modeling is also provided.  相似文献   
199.
This article examined the theoretical meanings of pension rights and analyzed their effects on women's economic risks in developed countries. First, based on the status of a citizen, worker, parent, and spouse, this study investigated how pension benefits are guaranteed as a citizen regardless of work history, the degree to which women's disadvantageous situations in the labor market and unpaid work are compensated by public pension as workers and parents, and how marital status is treated in the different pension systems. Second, analysis of the effect of pension rights showed that individual rights is a significant factor to prevent economic risks of elderly women. Derived rights did not seem to secure the economic welfare of elderly women, at least in a comparative context. This finding suggested that developing individual rights, rather than derived rights, is the way to guarantee long‐term elderly women's economic welfare.  相似文献   
200.
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