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On some sample size formulae for controlling both size and power in clinical trials.

Liu, W. (1997) On some sample size formulae for controlling both size and power in clinical trials. Journal of the Royal Statistical Society: Series D (The Statistician), 46, (2), pp. 238-251. (doi:10.1111/1467-9884.00080).

Record type: Article


Suppose that observations are taken from a population with normal distribution N(?, ?2) where both ? and ?2 are unknown parameters. Our goal is to design a two-sided test of H0: ? = 0 against Ha: ?? 0 which has, at least approximately, size ? and power ? at |?| = d> 0, where ?, ? and d are three preassigned constants. The classical solution is Stein's two-stage procedure, which tends to oversampling, however. Three new procedures are proposed and studied in this paper. They all have both size and power very close to the target values ? and ? and require only a few more observations than the necessary sample size to achieve our goal if ?2 had been completely known.

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Published date: 1997
Organisations: Statistics


Local EPrints ID: 30091
PURE UUID: 4d0a0eeb-bfc5-432b-9633-efeae1966f33
ORCID for W. Liu: ORCID iD

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Date deposited: 14 Mar 2007
Last modified: 17 Jul 2017 15:55

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Author: W. Liu ORCID iD

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