power.matched {sizepower} | R Documentation |
This routine computes the individual power value for a matched-pairs design having n
treatment units and n
matched control units. This power value is the expected fraction of truly differentially expressed genes that will be correctly declared as differentially expressed by the tests.
power.matched(ER0, G0, absMu1, sigmad, n)
ER0 |
mean number of false positives. |
G0 |
anticipated number of genes in the experiment that are not differentially expressed. |
absMu1 |
absoulte mean difference in log-expression between treatment and control conditions as postulated under the alternative hypothesis H1. |
sigmad |
anticipated standard deviation of the difference in log-expression between matched treatment and control units. The relation between the standard deviation of the difference (sigmad ) and the experimental error standard deviation (sigma ) is sigmad=sqrt(2)/sigma . |
n |
the sample size for each group. |
power |
power. |
psi1 |
non-centrality parameter. |
Examples and explainations can be found in http://www.biostat.harvard.edu/people/faculty/mltlee/pdf/Web-power-matched050510.pdf.
Weiliang Qiu (weiliang.qiu@gmail.com), Mei-Ling Ting Lee (meilinglee@sph.osu.edu), George Alex Whitmore (george.whitmore@mcgill.ca)
Lee, M.-L. T. (2004). Analysis of Microarray Gene Expression Data. Kluwer Academic Publishers, ISBN 0-7923-7087-2.
Lee, M.-L. T., Whitmore, G. A. (2002). Power and sample size for DNA microarray studies. Statistics in Medicine, 21:3543-3570.
power.randomized
,
power.multi
,
sampleSize.randomized
,
sampleSize.matched
power.matched(ER0=2, G0=5000, absMu1=1, sigmad=0.4243, n=4)