Hello all, I'm having difficulty with setting up a mixed model using lme in the nlme package. To summarize my study, I am testing for effects of ornamentation on foraging behavior of wolf spiders. I tested spiders at two different ages (penultimate vs. mature) and of two different phenotypes (one species tested lacks ornamentation throughout life [non-ornamented males] while the other acquires ornamentation upon maturation [i.e. brush-legged males]). I tested a sample of brush-legged and non-ornamented males (as both penultimates and matures) in 2009, and an additional sample of brush-legged males in 2010 (as both penultimates and matures again) because I had a very small sample of brush-legged males in 2009.
I would like to set up my lme so the fixed effects are "age" (penultimate vs mature), "phenotype" (non-ornamented vs brush-legged), and "year" (2009 vs 2010) nested within "phenotype" to test for differences between the two samples of brush-legged males. Additionally I want to include "id" (a unique identification number given to each spider tested) as a random factor to account for testing each individual twice (once as a penultimate and once as a mature). So far I have the following code: lme(behavior ~ age*phenotype, random=~1|maturity/id, data) But I don't know how to include the code to nest year within phenotype while testing for all possible interactions. Any help would be greatly appreciated. Thank you! Mari Pesek ______________________________________________ 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.