Romain, Look for info on mixed models. In R you do this either with the library nlme or lme4.
A good starting point is an article by Doug Bates in Rnews http://cran.r-project.org/doc/Rnews/Rnews_2005-1.pdf Joris [EMAIL PROTECTED] wrote on 13/02/2007 17:16:41: > > Hello, > > Does somebody could help me in the computation(formulation) of a > hierarchical ANOVA using linear model in R? > I'm working in a population biology study of an endangered species. My aim > is to see if I have effects of "Density of individuals/m2" on several > measured plants fitness traits. > > As independent variables I have: > > Humidity (continuous) > Nutritive substance (continuous) > LUX (continuous) > Density of individuals/m2 (continuous) > Population (categorical) > Year (categorical) > > I want to test the 4 continous variables with Population as error term. And > the Population, the Year and interaction term, with the error of Population > x Year. > > Thank you for any help, best regards. > > Romain Mayor > > ______________________________________________ > R-help@stat.math.ethz.ch 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@stat.math.ethz.ch 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.