Hi, I am having some trouble to find the correct syntax in R for analysing my results. I am running a experiment in which we measure the force exerted by the subjects (the independent variable) under two different fixed factors. Each factor has two levels, so that each subject participated to several repetitions of those four kinds of trials. I think that I should consider the subjects here as a random effect. My specific problem is that we are interested on investigating the effect of an end-state in each trial (say, the controlled point on the screen ended to the right or to the left) on the exerted force. I think that this later factor should also be considered as a random effect, but I am not sure. My question is how do I specify this model using aov() in R. I am not very used to statitics, and perhaps my question has a trivial answer. If this is the case, please give the pointers where I can find more information on this problem. Thank you in advance for any help, -- Rafael Laboissiere