> > At the moment, I am using an SPSS function (orthoplan) for my > needs. It provides factorial design with only main effects > (small orthogonal designs). > Since SPSS is very expensive (in particular with this > add-on), I would like to use R as for all my other projects > and research activity.
Yes, you're right. For, say, a 3 x 5 design, one can do this in as few as 7 runs -- but only in general by some version of one-factor-at-a-time (OFAT) designs, which are inefficient. It is easy, via, say model.matrix() to write a general function to produce these. But I think it's a bad idea; more efiicient algorithmic designs are better, IMO, which is why I suggested AlgDesign. You and others are free to disagree, of course. Cheers, Bert > > Do you know any other way to produce these designs in R? > > Thanks in advance, > > Roberto Furlan > University of Turin, Italy > > > > ---------------------------------------- > La mia Cartella di Posta in Arrivo รจ protetta con SPAMfighter > 188 messaggi contenenti spam sono stati bloccati con successo. > Scarica gratuitamente SPAMfighter! > > ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
