Dear list, Has anyone a suggestion for a package/tool that will generate microarray data (according to some desired/provided distribution) to be used in a simulation study? Now i am using the code below, but i wondered whether something more appropriate is available. Thanks, Guido set.seed(1) x1 <- rnorm(1000, mean = 6.0, sd = 2.81) x2 <- rnorm(1000, mean = 6.01, sd = 2.81) x3 <- rnorm(1000, mean = 5.99, sd = 2.81) grp1=cbind(x1,x2,x3) #repeat for other group of n=3. ------------------------------------------------ Guido Hooiveld, PhD Nutrition, Metabolism & Genomics Group Division of Human Nutrition Wageningen University Biotechnion, Bomenweg 2 NL-6703 HD Wageningen the Netherlands tel: (+)31 317 485788 fax: (+)31 317 483342 internet: http://nutrigene.4t.com<http: nutrigene.4t.com=""/> email: guido.hooiveld@wur.nl [[alternative HTML version deleted]]

Hello Guido, For simulation of microarray data we use the approach described by M. Langaas(2005, Journal of the Royal Statistical Society Series B). An R implemenation can be found in scripts that were provided by an article of us see: http://www.humgen.nl/MicroarrayAnalysisGroup.html under section "Selected publications" Filtering, FDR and power. The zip-file. Cheers, Maarten -- Maarten van Iterson Center for Human and Clinical Genetics Leiden University Medical Center (LUMC) Research Building, Einthovenweg 20 Room S-04-038 Phone: 071-526 9439 E-mail: M.van_iterson.HG at lumc.nl --------------- Postal address: Postzone S-04-P Postbus 9600 2300 RC Leiden The Netherlands