Dear Nils, You might also take a look at the Anova() function in the car package, which though less flexible than anova() should get you the tests that you want more simply. ?Anova has an example of a repeated-measures ANOVA with two within-subject and two between-subject factors.
I hope that this helps, John ------------------------------ John Fox, Professor Department of Sociology McMaster University Hamilton, Ontario, Canada web: socserv.mcmaster.ca/jfox > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of Skotara > Sent: December-05-08 8:40 AM > To: Peter Dalgaard; r-help@r-project.org > Subject: Re: [R] How to get Greenhouse-Geisser epsilons from anova? > > Dear Mr. Daalgard. > > thank you very much for your reply, it helped me to progress a bit. > > The following works fine: > dd <- expand.grid(C = 1:7, B= c("r", "l"), A= c("c", "f")) > myma <- as.matrix(myma) #myma is a 12 by 28 list > mlmfit <- lm(myma~1) > mlmfit0 <- update(mlmfit, ~0) > anova(mlmfit, mlmfit0, X= ~C+B, M = ~A+C+B, idata = dd, > test="Spherical"), which tests the main effect of A. > anova(mlmfit, mlmfit0, X= ~A+C, M = ~A+C+B, idata = dd, > test="Spherical"), which tests the main effect of B. > > > However, I can not figure out how this works for the other effects. > If I try: > anova(mlmfit, mlmfit0, X= ~A+B, M = ~A+C+B, idata = dd, test="Spherical") > > I get: > Fehler in function (object, ..., test = c("Pillai", "Wilks", > "Hotelling-Lawley", : > residuals have rank 1 < 4 > > I also don't know how I can calculate the various interactions.. > My read is I should change the second argument mlmfit0, too, but I can't > figure out how... > > Do you know what to do? > Thank you very much! > > > > Peter Dalgaard schrieb: > > Skotara wrote: > >> Dear all, > >> > >> I apologize for my basic question. > >> I try to calculate an anova for repeated measurements with 3 factors > >> (A,B,C) having 2, 2, and 7 levels. > >> or with an additional fourth between subjects factor D. > >> Everything works fine using > >> aov(val ~ A*B*C + Error(subject/ (A*B*C) ) ) or > >> aov(val ~ (D*A*B*C) + Error(subject/(A*B*C)) + D ) > >> val, A, B, C, D and subject are columns in a data.frame. > >> > >> How can I get the estimated Greenhouse-Geisser and Huynh-Feldt epsilons? > >> I know Peter Dalgaard described it in R-News Vol. 7/2, October 2007. > >> However, unfortunately I am not able to apply that using my data... > > > > Why? It is supposed to work. You just need to work out the X and M > > specification for the relevant error strata and set test="Spherical" > > for anova.mlm, or work out the T contrast matrix explicitly if that > > suits your temper better. > > > >> Furthermore, I am still confused of how SPSS calculates the epsilons > >> since it is mentioned that perhaps there are any errors in SPSS?? > >> > >> I would be glad if anyone could help me! > >> I am looking forward to hearing from you! > >> > >> Thank you! > >> Nils > >> > >> ______________________________________________ > >> 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. > > > > > > ______________________________________________ > 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. ______________________________________________ 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.