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31.
This article describes how a frequentist model averaging approach can be used for concentration–QT analyses in the context of thorough QTc studies. Based on simulations, we have concluded that starting from three candidate model families (linear, exponential, and Emax) the model averaging approach leads to treatment effect estimates that are quite robust with respect to the control of the type I error in nearly all simulated scenarios; in particular, with the model averaging approach, the type I error appears less sensitive to model misspecification than the widely used linear model. We noticed also few differences in terms of performance between the model averaging approach and the more classical model selection approach, but we believe that, despite both can be recommended in practice, the model averaging approach can be more appealing because of some deficiencies of model selection approach pointed out in the literature. We think that a model averaging or model selection approach should be systematically considered for conducting concentration–QT analyses. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
32.
In this article, we use cumulative residual Kullback-Leibler information (CRKL) and cumulative Kullback-Leibler information (CKL) to construct two goodness-of-fit test statistics for testing exponentiality with progressively Type-II censored data. The power of the proposed tests are compared with the power of goodness-of-fit test for exponentiality introduced by Balakrishnan et al. (2007 Balakrishnan, N., Habibi Rad, A., Arghami, N.R. (2007). Testing exponentiality based on Kullback-Leibler information with progressively type-II censored data. IEEE Transactions on Reliability 56(2):301307.[Crossref], [Web of Science ®] [Google Scholar]). We show that when the hazard function of the alternative is monotone decreasing, the test based on CRKL has higher power and when the hazard function of the alternative is non-monotone, the test based on CKL has higher power. But, when it is monotone increasing the power difference between test based on CKL and their proposed test is not so remarkable. The use of the proposed tests is shown in an illustrative example.  相似文献   
33.
回顾几十年来学术研究的道路,开始把鲁迅研究以专著形式系列化。这里的系列,只能说是“小系”,而不是“大系”。在这基础上,扩大研究领域,撰写关于中国现代小说研究,现代文学史研究的论著,同时进行散文创作,出版几本散文集。学术界的前辈、同辈、后辈的学者,在著作和文章中对我的论著、作品,进行热情的评论、分析,至感。  相似文献   
34.
使用事件研究法,分析了我国公司发行可转换债券的市场反应。研究表明,我国公司发行可转换债券后市场没有出现显著负的反应,与股权再融资的市场反应明显不同,与国外可转换债券发行的市场反应有差异。政府的奖优政策是可转换债券市场反应特殊性的重要原因。  相似文献   
35.
BackgroundIn Ethiopia, maternal health service utilization is still unacceptably low. The societal and cultural factors that constrain women from attending these services have not yet been sufficiently explored. Using qualitative methods, we aimed to explore the factors that delay maternal health service utilization in eastern Ethiopia.MethodA total of 13 audio-recorded focus group discussions were conducted comprising 88 participants. We conducted separate group discussions with reproductive aged women, mothers-in-law, traditional birth attendants, husbands, and Health Extension Workers to capture their knowledge, practices, feelings, thoughts and attitudes towards maternal health service utilization. The recorded sessions were transcribed into the local language and then translated into English for analysis.ResultThe study identified a number of factors that may delay maternal health service utilization. Factors were grouped using the Three Delays model as a framework. Low level of awareness regarding need, poor involvement of husband, perceived absence of health problems, social power, community misperceptions and cultural restrictions, negative attitudes towards male midwives, acceptance of traditional birth attendants and poor social networking were Delay One factors. Lack of physical accessibility and high transportation costs were categorised as Delay Two factors for skilled birth care attendance. Perceived or experienced poor quality of care were categorised as Delay Three factors for both skilled birth and postnatal care utilization.ConclusionDespite the ongoing government measures to improve maternal health service utilization in Ethiopia, numerous factors continue to contribute to delays in service use, which in turn contribute to high maternal mortality.  相似文献   
36.
This study explored the case of a former addict, focusing on his existential self‐interpretation and identity transformation process. This study began from the question of whether philosophical processes related to existential self‐interpretation could lead to the formation of the concept of bottoming out and of identity transformation. To answer this question, the study analyzed the case of a male in his mid‐forties who was addicted to drugs for approximately 30 years and has only recently maintained abstinence. The study used the phenomenological approach to determine the meaning drugs held for him in each stage, and what drug‐related identity he had in each stage. Further, this study identified the integrative implications of these meanings in terms of existential self‐interpretation and identity transformation. The four different identities the man identified for the four stages of his life were juvenile delinquent, gang member, half‐gangster, and breadwinner, and the associated meanings drugs had for him during each period were “glue,” “filthy,” “leeches,” and “abstinence,” respectively. Finally, this study elucidated the integration of these meanings through the hermeneutic circle, identified the social welfare implications of the findings, and developed educational recommendations.  相似文献   
37.
Although the relationship between social protection and enterprise performance is much debated in the literature, evidence is particularly limited in the case of small and medium-sized enterprises in developing economies. Using census data from 2010 to 2014, this article examines how the provision of social security influenced business performance in Indonesia. The author finds that increased social security spending of 10 per cent is associated with a per-worker revenue gain of up to 2 per cent. Moreover, profits are not found to decrease with increased social protection coverage, suggesting that increasing worker benefits may be a worthwhile business investment.  相似文献   
38.
Policymakers’ demand for increased accountability has compelled organizations to pay more attention to internal evaluation capacity building (ECB). The existing literature about ECB has focused on capacity building experiences and organizational research, with limited attention on challenges that internal evaluation specialists face in building organizational evaluative capacity. To address this knowledge gap, we conducted a Delphi study with evaluation specialists in the United States’ Cooperative Extension Service and developed a consensus on the most pervasive ECB challenges as well as the most useful strategies for overcoming ECB challenges. Challenges identified in this study include limited time and resources, limited understanding of the value of evaluation, evaluation considered as an afterthought, and limited support and buy-in from administrators. Alternatively, strategies found in the study include a shift in an organizational culture where evaluation is appreciated, buy-in and support from administration, clarifying the importance of quality than quantity of evaluations, and a strategic approach to ECB. The challenges identified in this study have persisted for decades, meaning administrators must understand the persistence of these issues and make an earnest investment (financial and human resource) to make noticeable progress. The Delphi approach can be used more often to prioritize ECB efforts.  相似文献   
39.
We define the odd log-logistic exponential Gaussian regression with two systematic components, which extends the heteroscedastic Gaussian regression and it is suitable for bimodal data quite common in the agriculture area. We estimate the parameters by the method of maximum likelihood. Some simulations indicate that the maximum-likelihood estimators are accurate. The model assumptions are checked through case deletion and quantile residuals. The usefulness of the new regression model is illustrated by means of three real data sets in different areas of agriculture, where the data present bimodality.  相似文献   
40.
文章论述了学习<江泽民文选>要采取马克思主义的科学态度,即要结合时代背景和实践的历史进程,深刻领会其重大意义和精神实质;以坚持和发展相统一的观点指导理论学习;理论联系实际,结合人们所做的实际工作来学习;要反对各种不良倾向,以提高学习实效.  相似文献   
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