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101.
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   
102.
For many continuous distributions, a closed-form expression for their quantiles does not exist. Numerical approximations for their quantiles are developed on a distribution-by-distribution basis. This work develops a general approximation for quantiles using the Taylor expansion. Our method only requires that the distribution has a continuous probability density function and its derivatives can be derived to a certain order (usually 3 or 4). We demonstrate our unified approach by approximating the quantiles of the normal, exponential, and chi-square distributions. The approximation works well for these distributions.  相似文献   
103.
We conducted two studies to investigate the item-order effect on life satisfaction judgments. In Study 1, Japanese and American participants completed various life-domain satisfaction items either before or after completing general life satisfaction items. American respondents weighed the best life domains more strongly than Japanese respondents, in particular when they answered domain satisfaction items before making life satisfaction judgments. Overall, Japanese tended to weigh the worst life domains more heavily when making life satisfaction judgments than Americans. We hypothesized that the Japanese patterns of life satisfaction judgments come from the chronic attention to others’ perspective. To examine this hypothesis in Study 2, Japanese participants were exposed to either the “other are not watching” or the “other are watching” manipulation. As expected, when Japanese participants were led to believe that “others are not watching,” they judged their overall life satisfaction based more heavily on the best life domains (like Americans in Study 1).  相似文献   
104.
BackgroundSevere perineal tears sustained during childbirth cause significant distress and morbidity amongst women. The objective of this study was to compare the use of straight scissors for cutting an episiotomy with the use of curved scissors, which are designed to curve away from the anal sphincter.MethodsWe used a single-centre, randomised feasibility trial. The intervention was the use of curved scissors. Women were recruited during a prenatal visit and randomised in the delivery suite, when it became clear that an episiotomy was required. The feasibility outcomes were the proportion of women able to be recruited, randomised and followed up. We also calculated the incidence of obstetric anal sphincter injury when either straight or curved scissors were used to cut an episiotomy. Other outcomes assessed were pain, length of hospital stay, perineal infection and perineal dehiscence.ResultsOf the 155 patients recruited in the prenatal period, only 20 (12.9%) were eventually randomised at birth. The main reasons for the high loss were that women either did not have a vaginal delivery (38, 24.5%), or they did not need an episiotomy (72, 46.5%). Rates of obstetric anal sphincter injury and other outcomes were similar between groups.DiscussionAnal sphincter injury during childbirth remains an important problem. Although the use of curved scissors provides a theoretical solution, we found that the high attrition rate made feasibility of conducting a suitably powered, randomised trial using the current design untenable. Alternative strategies have been suggested to make any future study more viable.  相似文献   
105.
The main purpose of dose‐escalation trials is to identify the dose(s) that is/are safe and efficacious for further investigations in later studies. In this paper, we introduce dose‐escalation designs that incorporate both the dose‐limiting events and dose‐limiting toxicities (DLTs) and indicative responses of efficacy into the procedure. A flexible nonparametric model is used for modelling the continuous efficacy responses while a logistic model is used for the binary DLTs. Escalation decisions are based on the combination of the probabilities of DLTs and expected efficacy through a gain function. On the basis of this setup, we then introduce 2 types of Bayesian adaptive dose‐escalation strategies. The first type of procedures, called “single objective,” aims to identify and recommend a single dose, either the maximum tolerated dose, the highest dose that is considered as safe, or the optimal dose, a safe dose that gives optimum benefit risk. The second type, called “dual objective,” aims to jointly estimate both the maximum tolerated dose and the optimal dose accurately. The recommended doses obtained under these dose‐escalation procedures provide information about the safety and efficacy profile of the novel drug to facilitate later studies. We evaluate different strategies via simulations based on an example constructed from a real trial on patients with type 2 diabetes, and the use of stopping rules is assessed. We find that the nonparametric model estimates the efficacy responses well for different underlying true shapes. The dual‐objective designs give better results in terms of identifying the 2 real target doses compared to the single‐objective designs.  相似文献   
106.
Using a convenience sample of 318 undergraduate and graduate social work students (193 women and 125 men) from a public university in India, this study examined the differences between Indian social work students' perceptions toward the role of government in addressing social issues in India. Using Predictive Analytics Software (PASW) 18, several statistical procedures were conducted to analyze the relationship between social work students' demographic variables and their perceptions of the government's role in addressing social issues in India. The results indicated that older social work students were more likely to perceive that the government should ensure equal opportunities for citizens. Female social work students were more likely to perceive that the government should ensure housing for citizens. BSW students were more likely to perceive that the government should ensure employment of citizens. Macro social work students were more likely to perceive that the government should ensure equal opportunities, housing, food, employment, and health insurance for citizens. The findings of this study may help social work educational administrators and faculty in India to develop a curriculum that provides social work students with the opportunity to critically examine the complex relationship between age, gender, marital status, number of children, socioeconomic status, educational status, area of concentration, and the role of the government in addressing social issues. Doing so will prepare social work students and professionals to think and engage in a manner that will allow them to challenge and advocate for a change to the status quo.  相似文献   
107.
108.
The last two decades have seen an increasing focus on the activation of individuals receiving welfare benefits. This has entailed an attempt to transform employment assistance and social security systems to make them more employment‐friendly through the development of explicit linkages between social protection policies, labour market participation and labour market programs. At the same time there has been a growing interest in the concept of social inclusion, and social inclusion has been a commonly stated goal of activation programs. However, despite some synergies between these two approaches, in other respects it is not clear that they are always compatible. This paper explores the extent to which activation programs are central to the social inclusion approach and the similarities and differences between these approaches. It then briefly examines the evidence regarding the ability of activation programs to enhance social inclusion.  相似文献   
109.
110.
Integrating volunteers into social care is widely expected but rarely successful in practice. This paper discusses how the Community Care Centre Plan organising community volunteers to provide services to the elderly in Taiwan. This plan successfully integrated social workers and volunteers in a national system to offer service in local communities, showing a systemic practice of community care and a unique case of community-based and volunteer-based service. The purposes of this paper are to introduce the programme design and to understand how to integrate the mission of social workers and volunteers’ performance. The governmental policy and requirements, the role of social workers and the provision of voluntary community service which contributed to form the system were examined in this paper.  相似文献   
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