Hi R experts: I am new to mixed model commodity. I am tryping to specify a model using lmer in lme4 package. I am not sure if I am doing right, so I need your help....please...... Treatment / factor structure Year: level 1:3, the whole the experiment was repeated in three years, random factor village: level 1:2 # the level is much higher just three are shown as example, random factor Farm : level 1:9 # the level is much higher just three are shown as example, random factor Variety: 10 variety were grown (may or not be different at different years, farm, villages, some of them were repeated) (fixed effect) Thus layout of treatment structure would like the follows for each year - Year[1] Villlage[1] Farm[1] Variety: 1, 2, 8, 9, 6, 5 Farm[2] Variety: 6, 8, 9, 10, 4 Farm[3] Variety: 1, 2, 5, 6, 3, 7 Village[2] Farm[3] Variety: 6, 8, 3, 4, 2 Farm[4] Variety: 3, 8,1, 10, 2 Farm[5] Variety: 1, 2, 3, 4, 5, 6 I am interested in interactions as well as following is the model in my mind: Pijklm = M+Yi +Vj +YVij +F(YV)k(ij) +Gl +GYli +GVlj + GYVlij + eijklm (Y is for year, V = village, G = Variety, F = Farm) I tried the following model and command, am I right? lmer( gryld ~ 1 + (1|year) + (1|village) + (1|year:village) + (Farm|year:village) + variety + (1|variety:year) + (1|variety:village) + (1|year:variety:village) , data= mbtrail) My doubt is on specially on year component? how can put that effectively? Thank you for your time. I tried to post this to mixed model forum but I did not get any response. Sorry to post all of you, but my hope is my question is simple enough and bigger R community can help me ! Ram H -- Ram H [[alternative HTML version deleted]]