Adaptive and nonadaptive group sequential tests
نویسندگان
چکیده
منابع مشابه
Adaptive and non-adaptive group sequential tests
Methods have been proposed to re-design a clinical trial at an interim stage in order to increase power. In order to preserve the type I error rate, methods for unplanned design-change have to be defined in terms of non-sufficient statistics and this calls into question their efficiency and the credibility of conclusions reached. We evaluate schemes for adaptive re-design, extending the theoret...
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We investigate nonadaptive group testing designs for heterogeneous mixtures of objects, independently positive with individual prior probabilities. In our model of the prior probabilities, the objects occur in one of several disjoint subsets and the number of positives in each subset is known. Furthermore, the positives are “uniformly distributed” within the subsets. The expected number of unre...
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ژورنال
عنوان ژورنال: Biometrika
سال: 2006
ISSN: 1464-3510,0006-3444
DOI: 10.1093/biomet/93.1.1