10. The method of claim 1 , wherein determining the increment value further comprises: selecting a first increment value for a first selected geographic area, and selecting a second, lesser increment value for the selected geographic areas which surround the first geographic area based on a fall-off function.
10. The method of claim 1 , wherein determining the increment value further comprises: selecting a first increment value for a first selected geographic area, and selecting a second, lesser increment value for the selected geographic areas which surround the first geographic area based on a fall-off function. 12. The method of claim 10 , wherein determining the second increment value further comprises applying a parabolic function to the first increment value.