This article reports on an exploratory study of the measurement of commonality in the use of variables or measures by authors and groups of authors who have reported on studies of information retrieval system users. There is some similarity to co-citation analysis in that, when two individual papers
The use of simulation and bootstrap in information-based group sequential studies
โ Scribed by Daniel O. Scharfstein; Anastasios A. Tsiatis
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 186 KB
- Volume
- 17
- Category
- Article
- ISSN
- 0277-6715
No coin nor oath required. For personal study only.
โฆ Synopsis
In this paper, we present an information-based design and monitoring procedure which applies to any type of model for any type of group sequential study provided there is a unique parameter of interest one can estimate efficiently. Simulation techniques are described to handle the design phase of this procedure. Since designs depend on potentially unreliable guesses of nuisance parameters, we propose a bootstrap method that uses the information available at the interim analysis times to generate projections and prediction intervals for the time at which the study will be fully powered. A monitoring broad can use this information to decide whether a redesign of the trial is warranted. We also show how to use simulation to redesign studies in progress. We illustrate all of these techniques with data from AIDS Clinical Trial Group Protocol 021.
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