On Sat, 2008-05-10 at 13:21 +0200, Birgit Lemcke wrote: > Hello R-People! > > I am running R 2.7.0 on a Power Book (Tiger). (I am still R and > statistics beginner) > > Perhaps this is another stupid question of me, but I was wondering > how I know the needed random (set.seed) numbers, when running > randomForest (library randomForest) on a large dataset.
The seed is just a starting point for the RNG. You can draw as many numbers as you like once the RNG has been seeded. The ability to set the seed allows repeated runs of functions like randomForest to provide the same results for each run. This is a basic requirement of reproducible research. require(randomForest) set.seed(1) mod1 <- randomForest(Species ~ ., data = iris) mod2 <- randomForest(Species ~ ., data = iris) set.seed(1) mod3 <- randomForest(Species ~ ., data = iris) all.equal(mod1, mod2) all.equal(mod1, mod3) You could put whatever (within reason - up to limits of an integer in R) into the set.seed function, but the point is to provide the same number in the seed if you want to make sure your results are reproducible. HTH G > > Thanks in advance > > Birgit > > > > Birgit Lemcke > Institut für Systematische Botanik > Zollikerstrasse 107 > CH-8008 Zürich > Switzerland > Ph: +41 (0)44 634 8351 > [EMAIL PROTECTED] > > 175 Jahre UZH > «staunen.erleben.begreifen. Naturwissenschaft zum Anfassen.» > MNF-Jubiläumsevent für gross und klein. > 19. April 2008, 10.00 Uhr bis 02.00 Uhr > Campus Irchel, Winterthurerstrasse 190, 8057 Zürich > Weitere Informationen http://www.175jahre.uzh.ch/naturwissenschaft > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. -- %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% Dr. Gavin Simpson [t] +44 (0)20 7679 0522 ECRC, UCL Geography, [f] +44 (0)20 7679 0565 Pearson Building, [e] gavin.simpsonATNOSPAMucl.ac.uk Gower Street, London [w] http://www.ucl.ac.uk/~ucfagls/ UK. WC1E 6BT. [w] http://www.freshwaters.org.uk %~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~%~% ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.