Hi All, I would like to ask a clarification about a nested anova. I did an experiment where I check for size differencies in flies. I have: 4 selection lines 3 cage nested in each selection line (12 cages overall) 5 vials nested within each cage (15 vials per line, 60 overall) I started out with the code: aov(area ~ selection + cage:selection + vial:cage:selection, scf) which does not exactly do what I would want (but gives me a fast reading of the SS I should expect) The code: aov(area ~ selection/cage/vial+ Error(selection/cage/vial),scf) does the trick (althought does not calculate the F value for me) (BTW, the slighty shorted code aov(area ~ selection/cage+ Error(selection/cage/vial),scf) gives the same results). Now, the question: assuming that "selection" is a fixed effect and "cage" and "vial" are random, how do I do the same analysis using lme? I tried to no avail. Regards, Federico Calboli ======================== Federico C.F. Calboli Department of Biology University College London Room 327 Darwin Building Gower Street London WClE 6BT Tel: (+44) 020 7679 4395 Fax (+44) 020 7679 7096 f.calboli at ucl.ac.uk