I've been using the randomForest package and getting very useful results for some time now. I have a question pertaining to variable interactions. Since, unlike CART, no single tree representative of the solution is available, I was wondering if there was some way of discerning / identifying potential interactions in the data. I'll sometimes produce 2-way partial dependence plots but I select variables for these plots somewhat arbitrarily (i.e. without prior suggestion of interaction). On Breimans’ website he mentions an experimental approach to identify interactions. I know this has come up before, a couple years ago, and Andy Liaw noted it was not implemented in part due to its experimental nature. I was wondering if anyone had a suggestion for detecting interactions using the randomForest package (In an analogous manner to Breimans' suggestion or another approach). Many Thanks, Joe Retzer [[alternative HTML version deleted]]