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There is an emerging consensus in empirical finance that realized volatility series typically display long range dependence with a memory parameter (d) around 0.4 (Andersen et al., 2001; Martens et al., 2004). The present article provides some illustrative analysis of how long memory may arise from the accumulative process underlying realized volatility. The article also uses results in Lieberman and Phillips (2004, 2005) to refine statistical inference about d by higher order theory. Standard asymptotic theory has an O(n-1/2) error rate for error rejection probabilities, and the theory used here refines the approximation to an error rate of o(n-1/2). The new formula is independent of unknown parameters, is simple to calculate and user-friendly. The method is applied to test whether the reported long memory parameter estimates of Andersen et al. (2001) and Martens et al. (2004) differ significantly from the lower boundary (d = 0.5) of nonstationary long memory, and generally confirms earlier findings.  相似文献   
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The International Conference on Harmonisation guideline ‘Statistical Principles for Clinical Trials’ was adopted by the Committee for Proprietary Medicinal Products (CPMP) in March 1998, and consequently is operational in Europe. Since then more detailed guidance on selected topics has been issued by the CPMP in the form of ‘Points to Consider’ documents. The intent of these was to give guidance particularly to non‐statistical reviewers within regulatory authorities, although of course they also provide a good source of information for pharmaceutical industry statisticians. In addition, the Food and Drug Administration has recently issued a draft guideline on data monitoring committees. In November 2002 a one‐day discussion forum was held in London by Statisticians in the Pharmaceutical Industry (PSI). The aim of the meeting was to discuss how statisticians were responding to some of the issues covered in these new guidelines, and to document consensus views where they existed. The forum was attended by industry, academic and regulatory statisticians. This paper outlines the questions raised, resulting discussions and consensus views reached. It is clear from the guidelines and discussions at the workshop that the statistical analysis strategy must be planned during the design phase of a clinical trial and carefully documented. Once the study is complete the analysis strategy should be thoughtfully executed and the findings reported. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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刻意创新     
我们大多数人都认同创新是成长的关键途径。问题是如何创新?许多企业依靠突发机遇。也就是说,他们指望某个人提出产品或服务方面的点子,然后从中获利。然而有些时候,企业必须发掘比以往更多的创意,并先于竞争对手将创意化为切实可行的产品与服务。此时,企业便不能再依靠机缘巧合了。我们需要可持续、可重复的创新方法。  相似文献   
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We interviewed 18 family caregivers about their communication experiences in the ICUs at an urban hospital. Analysis of their narratives suggests health literacy is important in family caregiver/healthcare provider communication, especially as complicated illnesses move the caregiver deeper into decision making. Using the domains of Yuen et al.’s conceptual model of caregiver health literacy (2015), we identified three themes within the context of ICU communication: agency, coordinated communication, and caregiver’s evolving role. We saw family caregivers negotiating domains of health literacy as they built upon knowledge of the patient’s needs, their rights as family caregivers, and the hierarchy of the professional staff. We found that these narratives represent co-created, or relational communication, rather than individual health literacy skills. Conceptualized in the transaction of relationship, health literacy is enacted; it is socially constructed and is the scaffolding upon which family caregivers make decisions, care for their loved one, and care for themselves.  相似文献   
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The percentage of female-headed African American families has increased significantly since the 1960s. It is now estimated that over half of all African American children will grow up in a female-headed household. This article examines factors related to the formation of these households as well as the challenges associated with these households. Policies and programs that have been implemented to treat these families are examined.  相似文献   
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(Continued from the last issue)However,I did not feel I had made the right choice and the next time I saw her I apologized.She said to me I had done nothing wrong and said "it’s not your fault teacher,it’s my fault my English is too poor." But I still insisted that I had made a mistake.Yes,I had corrected her,but at what cost? The experience obviously embarrassed her,and her peers by the third time she repeated the word incorrectly had been shaking their heads.She may have left the classroom being able to pronounce the word correctly but what about the damage to her confidence? I thought about it for literally hours.I feared that perhaps next time she might not want to stand up,or shout out the answer in class in case she might be humiliated again.In her mind it was her own incompetence but for me it was my own ignorance.  相似文献   
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The Revised Dyadic Adjustment Scale (RDAS; Busby, Crane, Larson, & Christensen, 1995) is a measure of couple relationship adjustment that is often used to differentiate between distressed and non‐distressed couples. While the measure currently allows for a determination of whether group mean scores change significantly across administrations, it lacks the ability to determine whether an individual's change in dyadic adjustment is clinically significant. This study addresses this limitation by establishing a cutoff of 47.31 and reliable change index of 11.58 for the RDAS by pooling data across multiple community and clinical samples. An individual whose score on the RDAS moves across the cutoff changes by 12 or more points can be classified as experiencing clinically significant change.  相似文献   
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The study purpose was to develop and pilot an undue influence screening tool for California’s Adult Protective Services (APS) personnel based on the definition of undue influence enacted into California law January 1, 2014. Methods included four focus groups with APS providers (n = 33), piloting the preliminary tool by APS personnel (n = 15), and interviews with four elder abuse experts and two APS administrators. Social service literature—including existing undue influence models—was reviewed, as were existing screening and assessment tools. Using the information from these various sources, the California Undue Influence Screening Tool (CUIST) was developed. It can be applied to APS cases and potentially adapted for use by other professionals and for use in other states. Implementation of the tool into APS practice, policy, procedures, and training of personnel will depend on the initiative of APS management. Future work will need to address the reliability and validity of CUIST.  相似文献   
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