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61.
This article considers short memory characteristics in a long memory process. We derive new asymptotic results for the sample autocorrelation difference ratios. We used these results to develop a new portmanteau test that determines if short memory parameters are statistically significant. In simulations, the new test can detect short memory components more often than the Ljung-Box test when these short memory components are in fact within a long memory process. Interestingly, our test finds short memory autocorrelations in U.S. inflation rate data, whereas the Ljung-Box test fails to find these autocorrelations. Modeling these short memory autocorrelations of the inflation rate data leads to improved model accuracy and more precise prediction.  相似文献   
62.
Through an Access to Information Act request, we have obtained the consent forms used by the providers of every human embryonic stem cell (hESC) line approved for use by the Canadian Institutes of Health Research (CIHR), and examined them to verify whether or not they meet the consent requirements established by Canadian law and regulations. Our findings show that at least seven out of ten consent forms studied did not satisfy these minimum requirements. We then outline various options for responding to this situation in terms of: (i) remedial measures for dealing with executive problems with regulatory oversight procedures; and (ii) remedial measures for dealing with the impugned lines.  相似文献   
63.
Multi–sectoral approaches to health improvement in its broadest sense have entailed an emphasis by the British government upon partnership working in and around community involvement in planning processes. New service planning and delivery organizations in the health service—primary care groups and primary care trusts—thus have to ensure that public and patient involvement strategies reflect a coordinated, if not integrated, multi–sectoral approach to such involvement. But how are these enforced partnership arrangements shaping the approach taken by primary care groups and trusts to the issue of public and patient involvement? More particularly, is the traditional dominance of health service managers and the medical profession in decision–making processes under challenge? This article draws on a study of primary care groups and trusts in three districts in order to gauge perceptions and calculations with regard to partnerships for involvement. Results appear to suggest that health service managers and practitioners continue to exercise considerable influence in comparison to that of patients and citizens. But, if the findings are viewed in the broader contexts of government managerialist strategies of surveillance and accountability and the growth of service–user and advocacy organizations, partnerships may offer significant scope for “lay” challenges to managerial and medical power.  相似文献   
64.
Sex offenders and sex crimes provoke a great deal of anxiety in our society, and over the past decade, lawmakers have passed a variety of social policies designed to protect the public from sexual victimization. The purpose of this study was to examine public perceptions about sex offenders and community protection policies. Data were obtained from a sample of 193 residents in Melbourne, Florida. It was hypothesized that the public holds some inaccurate beliefs about sex offenders, and that there is strong public support for community protection policies. It was found that community members believe that sex offenders have very high recidivism rates, view sex offenders as a homogeneous group with regard to risk, and are skeptical about the benefits of sex offender treatment. The hypothesis that public perceptions contradict empirical research was supported. Community members were overwhelmingly in favor of public disclosure of information about registered sex offenders, although they did not express as much support for residence restrictions. Implications for public policy, and for the media's role in shaping public perceptions, are discussed.  相似文献   
65.
66.
Health Policy and the Politics of Evidence   总被引:1,自引:0,他引:1  
National decisions on the drugs, treatments and medical devices that should be funded through public expenditure are a fundamental element of health policy. But despite a political emphasis upon evidence‐based policy, the results of rigorous clinical trials and statistical modelling techniques rarely speak for themselves. So, does the pre‐eminence traditionally accorded to quantitative data in the medical field underpin policy decisions on a consistent basis? Or are more subtle, less transparent characteristics of context and interaction evident in the shaping of attendant decisions? This article considers these questions by drawing on a study of decision‐making in the National Institute for Health and Clinical Excellence (NICE)—an organization established by the British government in 1999 to decide whether selected health technologies should be made available throughout the National Health Service in England and Wales. In broad terms, the findings point to the primacy of arguments based on quantitatively oriented, experimentally derived data but also to a discursive hegemony of clinicians and health economists in mediating, including or debarring more qualitative, experientially based evidence. A more complex, dynamic understanding of policy governance in the field of health technology appraisal—founded on a discursive appropriation of the idea of the “common good”—goes some way to explaining the persistence of this hegemony despite an avowedly inclusive, plural approach to decision‐making.  相似文献   
67.
Optimal three-stage designs with equal sample sizes at each stage are presented and compared to fixed sample designs, fully sequential designs, designs restricted to use the fixed sample critical value at the final stage, and to modifications of other group sequential designs previously proposed in the literature. Typically, the greatest savings realized with interim analyses are obtained by the first interim look. More than 50% of the savings possible with a fully sequential design can be realized with a simple two-stage design. Three-stage designs can realize as much as 75% of the possible savings. Without much loss in efficiency, the designs can be modified so that the critical value at the final stage equals the usual fixed sample value while maintaining the overall level of significance, alleviating some potential confusion should a final stage be necessary. Some common group sequential designs, modified to allow early acceptance of the null hypothesis, are shown to be nearly optimal in some settings while performing poorly in others. An example is given to illustrate the use of several three-stage plans in the design of clinical trials.  相似文献   
68.
This paper describes the use and evaluation of the folder feedback system. The folder feedback system is a useful teaching tool based in principles of adult learning. It is designed to help organize student learning, increase communication with the instructor, insert an element of fun into the class, and assist with student/teacher relationship building. An evaluation of the teaching tool produced mixed results. The treatment group received higher grades than the comparison group, yet in all other measures no differences were found.  相似文献   
69.
Recent changes in American media have resulted in direct impacts on the work of PR professionals, from newsroom reductions in traditional media outlets to the rise of social media. This study examines changes in the media relations dynamic with qualitative, in-depth interviews from 12 PR professionals in a medium, eastern U.S. city. Findings include PR professionals doing less traditional media relations, mostly attributable to downsized newsrooms, and frustration with the resulting dearth of institutional knowledge, influx of young, inexperienced reporters, and shallow stories. While participants see opportunities to inject unfiltered messages in media, overall they value reporter relationships and using social media in communication with them and in their job. Although new media are seen as one more task on an already very full PR plate, participants acknowledge their importance and growing relevance. Overall, PR professionals see their and the industry's future including both traditional and new media.  相似文献   
70.
In a two-treatment trial, a two-sided test is often used to reach a conclusion, Usually we are interested in doing a two-sided test because of no prior preference between the two treatments and we want a three-decision framework. When a standard control is just as good as the new experimental treatment (which has the same toxicity and cost), then we will accept both treatments. Only when the standard control is clearly worse or better than the new experimental treatment, then we choose only one treatment. In this paper, we extend the concept of a two-sided test to the multiple treatment trial where three or more treatments are involved. The procedure turns out to be a subset selection procedure; however, the theoretical framework and performance requirement are different from the existing subset selection procedures. Two procedures (exclusion or inclusion) are developed here for the case of normal data with equal known variance. If the sample size is large, they can be applied with unknown variance and with the binomial data or survival data with random censoring.  相似文献   
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