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1.
In studies with recurrent event endpoints, misspecified assumptions of event rates or dispersion can lead to underpowered trials or overexposure of patients. Specification of overdispersion is often a particular problem as it is usually not reported in clinical trial publications. Changing event rates over the years have been described for some diseases, adding to the uncertainty in planning. To mitigate the risks of inadequate sample sizes, internal pilot study designs have been proposed with a preference for blinded sample size reestimation procedures, as they generally do not affect the type I error rate and maintain trial integrity. Blinded sample size reestimation procedures are available for trials with recurrent events as endpoints. However, the variance in the reestimated sample size can be considerable in particular with early sample size reviews. Motivated by a randomized controlled trial in paediatric multiple sclerosis, a rare neurological condition in children, we apply the concept of blinded continuous monitoring of information, which is known to reduce the variance in the resulting sample size. Assuming negative binomial distributions for the counts of recurrent relapses, we derive information criteria and propose blinded continuous monitoring procedures. The operating characteristics of these are assessed in Monte Carlo trial simulations demonstrating favourable properties with regard to type I error rate, power, and stopping time, ie, sample size.  相似文献   
2.
Modeling spatial overdispersion requires point process models with finite‐dimensional distributions that are overdisperse relative to the Poisson distribution. Fitting such models usually heavily relies on the properties of stationarity, ergodicity, and orderliness. In addition, although processes based on negative binomial finite‐dimensional distributions have been widely considered, they typically fail to simultaneously satisfy the three required properties for fitting. Indeed, it has been conjectured by Diggle and Milne that no negative binomial model can satisfy all three properties. In light of this, we change perspective and construct a new process based on a different overdisperse count model, namely, the generalized Waring (GW) distribution. While comparably tractable and flexible to negative binomial processes, the GW process is shown to possess all required properties and additionally span the negative binomial and Poisson processes as limiting cases. In this sense, the GW process provides an approximate resolution to the conundrum highlighted by Diggle and Milne.  相似文献   
3.
政治冲突的功能理论是政治冲突与整合理论的重要组成部分。由于目前对政治冲突与整合理论的研究非常少,所以作为它的重要组成部分的功能理论研究更为鲜见。本文在历史与逻辑相统一的理论框架下,结合前人的相关论述,特别是重点围绕马克思与L·科塞的观点,对政治冲突的功能:负功能和正功能进行了比较系统地分析。  相似文献   
4.
A role-reversal in the mother-daughter relationship   总被引:1,自引:1,他引:0  
Psychoanalytic theorists have noted a particular dynamic in the mother-infant relationship in which the emotional needs of the mother predominate. When this situation occurs, the emotional needs of the infant may go unmet, resulting in impaired self-development. Through an integration of the ideas of mainstream psychoanalytic theorists and feminist psychoanalytic thinkers, this paper proposes the idea that, because of the intensity of the mother-daughter relationship, this dynamic may be more prevalent between mothers and daughters than between mothers and sons. A mother-daughter relationship is described in which the mother comes to depend on her daughter for emotional attunement and response, and the mother's selfobject needs predominate. As a consequence, the daughter is unable to develop a cohesive sense of self and experiences difficulty in achieving separation. Two clinical reports are presented to illustrate the way in which this mother-daughter dynamic manifests itself in the patient's life and in the therapeutic relationship. A negative transference dynamic is described resulting from these patient's fear of duplicating their relationship with their mothers in the therapeutic relationship by having to meet the selfobject needs of the therapist.  相似文献   
5.
影视文化中的消极因素是当代青少年犯罪的一个重要原因.影视文化中的消极因素影响了当代青少年的世界观、人生观、价值观、政治观和道德观.要有效预防和控制当代青少年犯罪就必须消除影视文化的"负面效应".大力弘扬时代的主旋律,严格加强文化市场的管理,科学制定<影视文化法>,积极加强影视文化的评论,努力形成"合力效应".  相似文献   
6.
甲骨文中的否定词比较丰富,它们的用法也不完全相同。研究这些否定词的用法,不仅丰富汉语史的内容,而且也看到,秦汉时期汉语中某些否定词的用法,早在3000年前的殷商时代就已形成,说明汉语的历史的确是悠久而又丰富的。  相似文献   
7.
英汉基本句类主位结构对比及翻译   总被引:2,自引:0,他引:2  
从语篇分析的角度,运用系统功能语法理论,通过对英汉基本句类的主述位结构的对比分析,探讨如何在翻译中处理主述位错位现象的问题。  相似文献   
8.
从唐末至今 ,论者对晚唐诗大多持否定态度。反思这种带有明显历史惯性的批评现象 ,不难发现 ,不是晚唐诗缺乏思想价值和艺术魅力 ,而是其出现的异于此前诗坛的人生哲学、生活情趣、审美情趣、艺术思维和艺术风格 ,不仅使那些视文学为伦理、政治奴婢的封建文学观念批评者难以认同 ,也使那些对思想文化史发展缺乏认识和分析的批评者 ,难以理解出现在晚唐诗中的种种变化 ,因而导致千余年来的批评失误  相似文献   
9.
本文指出学生综合运用英语阅读能力的重要性,并提出提高学生英语阅读能力所采用的方法。经过教学实验证明,如果学生掌握了一些阅读技巧,就会提高阅读速度和阅读理解能力。  相似文献   
10.
英汉句法存在三种最基本的差异 ,即树型结构和线型结构、形合法和意合法以及句子界线的差异。在此基础上 ,着重介绍英汉互译过程中的三种转换方法  相似文献   
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