On Thu, 2007-11-15 at 16:36 +0100, Johan A. Stenberg wrote: > Dear all, > > I'm quite sure that this is a stupid question, but I'll ask anyway. > I want to perform an ANCOVA with two continuous factors and three > categorical factors. > > Plant population growth rate (GR) = dependent variable > Seed reduction due to herbivory (SR) = continuous explanatory variable > Herbivore species (HS, 2 levels) = categorical explanatory variable > Population (Pop, 24 levels) = categorical explanatory variable > Population size (Popsize) = continuous explanatory variable > Year (Year, 16 levels) = categorical explanatory variable > > My model is technically simple: > > model<-aov(GR~SR*HS*Pop*Popsize*Year) > > However, R is not returning any F and P values – only Df, Sum Sq and > Mean Sq. I have to remove either Year or Pop in order to get the test > statistics. Why is this? > > Thank you in advance! > Johan A. Stenberg, Umea University, Sweden
See ?summary.aov which is referenced in the "See Also" section of ?aov and is used in the examples therein. HTH, Marc Schwartz ______________________________________________ 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.
