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81.
介绍了潜在成长模型的发展、类型和内容,通过分析、归纳、整理等,比较了潜在成长模型与传统t检验、方差分析、回归分析的差别,探讨了潜在成长模型研究设计的要求,通过台湾棒球职业球员薪酬成长模型说明。利用文献调查法,分析了LGM潜在成长模型在体育运动领域中应用的概况,举例说明体育运动领域应用LGM的情况,证实了未来潜在成长模型会在体育科学领域逐渐受到重视并得到快速发展。  相似文献   
82.
Patient heterogeneity may complicate dose‐finding in phase 1 clinical trials if the dose‐toxicity curves differ between subgroups. Conducting separate trials within subgroups may lead to infeasibly small sample sizes in subgroups having low prevalence. Alternatively,it is not obvious how to conduct a single trial while accounting for heterogeneity. To address this problem,we consider a generalization of the continual reassessment method on the basis of a hierarchical Bayesian dose‐toxicity model that borrows strength between subgroups under the assumption that the subgroups are exchangeable. We evaluate a design using this model that includes subgroup‐specific dose selection and safety rules. A simulation study is presented that includes comparison of this method to 3 alternative approaches,on the basis of nonhierarchical models,that make different types of assumptions about within‐subgroup dose‐toxicity curves. The simulations show that the hierarchical model‐based method is recommended in settings where the dose‐toxicity curves are exchangeable between subgroups. We present practical guidelines for application and provide computer programs for trial simulation and conduct.  相似文献   
83.
Our study aims at describing mortality among reported elder abuse experiences in rural Malaysia. This is a population-based cohort study with a multistage cluster sampling method. Older adults in Kuala Pilah (n = 1,927) were interviewed from November 2013 to May 2014. Mortality was traced after 2 years using the National Registration Department database. Overall, 139 (7.2%) respondents died. Fifteen (9.6%) abuse victims died compared to 124 (7.0%) not abused. Mortality was highest with financial abuse (13%), followed by psychological abuse (10.8%). There was a dose-response relationship between mortality and clustering of abuse: 7%, 7.7%, and 14.0% for no abuse, one type, and two types or more, respectively. Among abuse victims, 40% of deaths had ill-defined causes, 33% were respiratory-related, and 27% had cardiovascular and metabolic origin. Results suggest a link between abuse and mortality. Death proportions varied according to abuse subtypes and gender.  相似文献   
84.
As a result of aging populations, institutionalization of older people is creating an increasing financial burden in many countries. The purpose of the present study was to explore the impact of in-home service utilization on institutionalization. The subjects were newly certified as eligible for long-term care insurance between January and February 2009 in Korea. The follow-up period was 40 months, to April 2012. We used logistic regression models to identify factors influencing the transition to institutional service, adjusting for gender, age, living status, income level, activities of daily living, and chronic disease. The institutionalization rate was estimated to be 17.3% over 40 months. The interval from transitional living to institutionalization was 36 ± 8 months. Risk factors of transition to institutional services are being female, having advanced age, living with friends or cousins, getting dementia, and not using in-home services. We determined that institutionalization is mitigated by use of in-home services. Therefore, supplying appropriate in-home services to current nonusers would help to greatly reduce the rate of institutionalization of older people.  相似文献   
85.
Why is there so much confusion and conflict around common identity labels, a problem that extends well beyond any stereotypes that they may evoke? How do we escape the seeming paradox that we reject racism but still speak frequently of black and white? Who claims the power to determine or name others’ identities? The confusion and conflict about identity that play out on a surface level are often caused by starkly different but implicit understandings that operate beneath the surface. For example, terms like black, Jewish and Muslim may invoke several of our deeper conceptions or categories like race, culture, religion and ethnicity, and to varying degrees in different places. Critically, these categories themselves are culturally rooted. This article shows how our implicit categories can lead to both cross-cultural confusion and problematic misunderstandings in course content. Helping students to recognise and to understand the cultural roots of our implicit categories should be a deliberate learning outcome. This type of cultural understanding can be advanced significantly through guided reflection on experience and explicit instruction; in addition, some subjects and approaches – intercultural education, study abroad and Holocaust education among them – show particular promise for achieving this aim.  相似文献   
86.
Psycho-education interventions for families affected by parental mental illness have been found to be effective. This study aimed to assess the feasibility of a psycho-educational resource for parents, designed to initiate family discussions about parental mental illness and educate parents about the impact of their illness on children. In a mixed methods design, 19 parents read the “Let’s Talk About Children” psycho-educational resource and completed pre-and-post questionnaires measuring their perspectives of mental illness and awareness of the impact of mental illness on their children and family. 18 of these participated in a follow-up, one hour, individual interview to obtain further feedback on the resource. After viewing the resource, changes in parents’ attitudes and/or behavior in relation to mental illness and parenting were recorded. Interview findings indicate that the resource gave parents an awareness of the skills and knowledge needed for initiating family discussions about parental mental illness. The results of this study can be used to inform future interventions targeting parents who experience mental illness.  相似文献   
87.
88.
Frailty models can be fit as mixed-effects Poisson models after transforming time-to-event data to the Poisson model framework. We assess, through simulations, the robustness of Poisson likelihood estimation for Cox proportional hazards models with log-normal frailties under misspecified frailty distribution. The log-gamma and Laplace distributions were used as true distributions for frailties on a natural log scale. Factors such as the magnitude of heterogeneity, censoring rate, number and sizes of groups were explored. In the simulations, the Poisson modeling approach that assumes log-normally distributed frailties provided accurate estimates of within- and between-group fixed effects even under a misspecified frailty distribution. Non-robust estimation of variance components was observed in the situations of substantial heterogeneity, large event rates, or high data dimensions.  相似文献   
89.
Turing's formula is an amazing result that allows one to estimate the probability of observing something that has not been observed before. After a brief review of the literature, we perform a simulation study to better understand how well this formula works in a variety of situations. We also compare the performance of Turing's formula with several modifications that have appeared in the literature. We find that these modifications tend to outperform Turing's formula, but usually not by very much. We further find that Turing's formula and its modifications tend to work better for heavy-tailed distributions than for light-tailed ones.  相似文献   
90.
This paper addresses the problem of estimating a general parameter using information on an auxiliary variable X. We have suggested a class of exponential-type ratio estimators for the parameter and its properties are studied. It is identified that the estimators due to Upadhyaya et al. [Journal of Statistical Theory and Practice (2011), 5(2), 285–302] and Yadav and Kadilar [Revista Columbiana de Estadistica, (2013), 36(1), 145–152] are members of the proposed estimator. We have also shown that the suggested estimator is more efficient than the estimators of Upadhyaya et al. (2011 Upadhyaya, L.N., Singh, H.P., Chatterjee, S., Yadav, R. (2011). Improved ratio and product exponential type estimators. J. Stat. Theo. Pract. 5 (2): 285302.[Taylor &; Francis Online] [Google Scholar]) and Yadav and Kadilar (2013 Yadav, S.K., Kadilar, C. (2013). Improved exponential type ratio estimator of population variance. Revis. Colum. de Estadist. 36(1): 145152. [Google Scholar]). Numerical illustration is provided in support of the present study.  相似文献   
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