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1.
To capture mean and variance asymmetries and time‐varying volatility in financial time series, we generalize the threshold stochastic volatility (THSV) model and incorporate a heavy‐tailed error distribution. Unlike existing stochastic volatility models, this model simultaneously accounts for uncertainty in the unobserved threshold value and in the time‐delay parameter. Self‐exciting and exogenous threshold variables are considered to investigate the impact of a number of market news variables on volatility changes. Adopting a Bayesian approach, we use Markov chain Monte Carlo methods to estimate all unknown parameters and latent variables. A simulation experiment demonstrates good estimation performance for reasonable sample sizes. In a study of two international financial market indices, we consider two variants of the generalized THSV model, with US market news as the threshold variable. Finally, we compare models using Bayesian forecasting in a value‐at‐risk (VaR) study. The results show that our proposed model can generate more accurate VaR forecasts than can standard models.  相似文献   
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Changes occurring in health care demand that physicians expand their professional knowledge and skills beyond the medical and behavioral sciences. Subjects absent from traditional medical education curricula, such as the economics and politics of health care, practice management, and leadership of professional organizations, will become important competencies, particularly for physicians who serve in management roles. Because physicians occupy a central role in planning and allocating medical care services and other health care resources, they must be better prepared to work with other health care professionals to create a new civilization, even if this means leaving the cloistered domain of "physician land" to serve as interface professionals between the delivery of medical services and the management of health care. Our research findings and conclusions strongly suggest that economic, management, and leadership competencies need to be incorporated into the professional development of physicians, especially in postgraduate and continuing education curricula.  相似文献   
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Physical activity is a well recognized approach to the enhancement of general health and wellbeing in both healthy and diseased populations. However, excessive activity can result in exercise-related menstrual dysfunction (ERMD), which can adversely affect bone health and increase the risk of infertility and cardiovascular events in later life. Physicians should maintain a high awareness of EMRD in assessing health risks in the menopausal woman.  相似文献   
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This paper proposes a new hysteretic vector autoregressive (HVAR) model in which the regime switching may be delayed when the hysteresis variable lies in a hysteresis zone. We integrate an adapted multivariate Student-t distribution from amending the scale mixtures of normal distributions. This HVAR model allows for a higher degree of flexibility in the degrees of freedom for each time series. We use the proposed model to test for a causal relationship between any two target time series. Using posterior odds ratios, we overcome the limitations of the classical approach to multiple testing. Both simulated and real examples herein help illustrate the suggested methods. We apply the proposed HVAR model to investigate the causal relationship between the quarterly growth rates of gross domestic product of United Kingdom and United States. Moreover, we check the pairwise lagged dependence of daily PM2.5 levels in three districts of Taipei.  相似文献   
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Drawing from literature regarding public engagement, the Elaboration Likelihood Model (ELM), computer-mediated communication research, and emotion psychology, this study examines the effects of companies’ social media communication strategies on public engagement behaviors as indexed by post likes, shares, and comments. Specifically, it investigates how corporate Facebook posts’ functional traits (functional interactivity and vividness) and emotional traits (emotion presence, valence, and strength) impact public engagement online. Through data mining and computer-assisted sentiment analysis of 33,379 posts from 106 Standard & Poor 500 companies’ Facebook accounts, this study finds a negative effect of functional interactivity but a positive effect of vividness on engagement. It also shows that emotional traits overall yield stronger public engagement outcomes. Two-way interactions between emotional and functional features are also detected. Theoretical and practical implications are discussed.  相似文献   
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The majority of children and young people removed from the care of their parents by the state of Victoria, Australia, reside in foster or kinship care. These children have experienced a broad range of adverse conditions and are up to 4 times more likely to experience problems with mental health than their mainstream peers. This paper draws on the perspectives of foster and kinship carers, describing the disconnection between their role as mental health advocates and their interest in early intervention in a field which is dominated by crisis and the historic marginalisation of foster and kinship carers. Thirty‐one foster and kinship carers across greater metropolitan Melbourne, Australia, contributed to this study through interviews and focus groups. Participants demonstrated a practical understanding of mental health and an ability to identify a range of conditions that have an adverse impact on the mental health of children and young people in their care. The paper concludes that there is a lack of systemic support and even a range of barriers that affect the capacity of foster and kinship carers to promote the mental health and well‐being of the children and young people in their care.  相似文献   
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As international female labour migration has increased, so too have efforts to prevent the exploitation of labour migrants. However, evidence to underpin prevention efforts remains limited, with little known about labour migrants’ migration planning processes. Using data from a survey of female prospective labour migrants from Nepal, this article compares socio‐demographics and migration‐planning processes between first‐time and repeat‐migrants. We identified several factors which might increase repeat‐migrants’ vulnerability to exploitation during the migration process, or obstruct their engagement in pre‐migration interventions: more rapid migration planning than first‐time migrants; lower involvement in community groups; and a perception that they already have the knowledge they need. Only one‐third of repeat‐migrants planned to go to the same destination and 42 per cent to work in the same sector as previously. With repeat‐migration a common livelihoods strategy, it is crucial that interventions are guided by evidence on the needs of both first‐time‐ and repeat‐migrants.  相似文献   
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