called RES1 if no such variable exists, RES2 if RES1 already exists,
RES3 if RES1 and RES2 already exist, etc. It will choose the name of
the variable for the predicted values similarly, but with PRED as a
called RES1 if no such variable exists, RES2 if RES1 already exists,
RES3 if RES1 and RES2 already exist, etc. It will choose the name of
the variable for the predicted values similarly, but with PRED as a