text: what we mean when we say that an equation is driven?what we mean when we say that an equation is dumped?   usually, when someone says an equation or other relationship is driven by a particular variable, they mean that variable is dominant to the others.  i.e. changes to that variable will change the output of the function significantly, while changes to other variables may not.  as for dumped, i believe that it means certain terms of a larger equation are ignored because they are too small to be significant.