Here solid lines denote variables to be considered and grey boxes (dotted lines) denote decision criteria. Note: 1) Crossed out options are for example only, all options are available in real analysis tree. 2) For display purposes only included variables are written in full but variable selection at each level includes the same forks. 3) The third level criteria uses ascending steps to decide model variable inclusion. 4) Top of the tree denotes the basic model.