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China??s oldest old population is estimated to quadruple by 2050. Yet, poverty rate for the oldest old has been the highest among all age groups in China. This paper investigates the relationship between economic stress, quality of life, and mortality among the oldest-old in China. Both objective economic hardships and perceived economic strain are examined. We base our investigation on data drawn from the Chinese Longitudinal Healthy Longevity Survey conducted between 2000 and 2005. Our sample includes 10,972 men and women between the ages of 80 and 105 in 2000. The data show that about 16% of these oldest-old lived under economic stress in 2000. The risk factors that make one vulnerable to economic stress include age, being male, being widowed or never married, being a minority member, having no education, having no living children, and not having children as main source of income, and having no pension. Economic stress is negatively associated with indicators of quality of life, such as the quality of medical care and mental well-being. The poor quality of life contributes to the higher mortality rate for the oldest old who are under economic stress. Results also show that perceived economic strain increases the risk of mortality by 42% in rural areas, even after controlling for basic demographic characteristics, life style factors, and major health events.?For the rural oldest-old, having children as a main source of income and having access to pension alleviates the negative impact of economic hardship on mortality hazard by 23 and 66% respectively. However, in urban areas, economic stress has no direct impact on the hazard of mortality.  相似文献   
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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   
4.
The performance of the balanced half-sample, jackknife and linearization methods for estimating the variance of the combined ratio estimate is studied by means of a computer simulation using artificially generated non-normally distributed populations.

The results of this investigation demonstrate that the variance estimates for the combined ratio estimate may be highly biased and unstable when the underlying distributions are non-normal. This is particularly true when the number of observations available from each stratum is small. The jack-  相似文献   
5.
This article develops the locally uniformly most powerful unbiased Lagrange multiplier test of normality of regression disturbances within the family of power exponential distributions. The small sample power properties of the test are compared in a Monte Carlo study with 6 well-known tests across 12 alternative nonnormal distributions. In addition, the finite sample power properties for nonnormal alternatives within the power exponential family are summarized by estimating response surfaces. The results suggest that the proposed text is computationally convenient and possesses relatively attractive power properties even against alternatives outside the power exponential family.  相似文献   
6.
In 2004, we conducted a nationwide dual frame survey of landlineand cell phone numbers to evaluate the feasibility of includingcell phone numbers in a random digit dial telephone survey.Households with both landline and cell phones were eligiblefor selection in both samples. This article describes our designand data collection methods; compares the results from the twosamples (with an emphasis on operational characteristics); andpresents the outcomes of two experimental manipulations designedto improve the cell phone response rate.  相似文献   
7.
This paper describes a case that examines five key topics in production and operations management [1]—forecasting, inventory control, transportation planning, aggregate planning, and the disaggregation of the aggregate plan—in an integrated, realistic manner for upper-level undergraduate business majors [3]. The case structure stresses the linkage of these interrelated subjects and supplements the regular classroom presentations dealing with them. The case relies on computer calculations at each stage to provide the information input for calculations at the next stage. It is a static model with a twelve-month planning horizon. Students complete several exercises and assume several roles as the case unfolds. They act on their own in filling some roles and as members of teams in performing others. They do not compete with each other, as the purpose of the case is to help them develop an appreciation of the factors that persons performing the role must consider.  相似文献   
8.
With an emphasis placed on supply‐side interventions such as skills training and incentives enhancement, active labor market polices (ALMPs) are strongly promoted by international organizations and widely adopted across different welfare regimes to boost employment rates. This article first presents the under‐examined relationship between ALMPs and employment precariousness, which has posed a challenge to the neoliberal notion of employability and activation. Youth‐focused employment policies tend to speed up employment entry whilst downplaying the risk of precariousness and the importance of job quality, and thus further reinforcing the belief that engaging in precarious employment is tolerable if not inevitable. The article then examines the case of Hong Kong, which illustrates that its relatively low rate of youth unemployment may conceal the unfavorable employment conditions confronted by youth. It is argued that the service‐led employment policies and short‐term vocational training define the employability of young workers in terms of labor flexibilities. The coined phase of “flexi‐employability” is characterized by promoting youth's readiness for, and adaptability to, the volatilities and changing demands of the labor market. Arguably, the disciplinary approach to youth activation would only strengthen the work‐first principle by enforcing young people to take up jobs available and leave welfare as soon as possible, but without thoroughly addressing the risks and insecurities generated by the labor market in undermining their well‐being.  相似文献   
9.
This study investigates how growing up as a left-behind child due to parents’ labor migration in China is associated with adolescents’ cognitive and socioemotional development, based on data from the China Family Panel Studies. We find that adolescents do worst when both parents are absent in all developmental indicators we examined: short-term and long-term word recall tests, numeracy test, self-concept, and self-expectation of educational attainment. However, the differences between left-behind children and those in rural two-parent families are not statistically significant. Left-behind adolescents do have significantly lower well-being than those in urban two-parent families. These differences can largely be accounted for by father's education, family spending on the adolescent's education, quality of parenting, and the social support available to an adolescent. The gap in Chinese adolescents' development is, thus, not so much related directly to how many parents one grows up with as it is to whether one grows up in a rural or urban environment.  相似文献   
10.
This study compared the development of clinical assessment and intervention skills between students enrolled in a face-to-face (F2F) or an asynchronous online clinical social work class. All students from three semesters of F2F (n = 74) and online (n = 78) sections of an MSW clinical class taught by the same instructor were included. Two assignments were used to compare students: an assessment and treatment plan of a fictional case and a digital role-play. A doctoral student who was blinded to the course delivery mechanism graded the role-play. After controlling for baseline differences in age, there were no differences between online and F2F students in skill demonstration. It appears clinical skills can be taught as effectively online as in F2F situations based on blinded review of role-plays.  相似文献   
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