How to get Greenhouse-Geisser epsilons from anova?
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 at 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.
O__ ---- Peter Dalgaard ?ster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk) FAX: (+45) 35327907