20. The method of claim 12 , wherein the system is an on-board computer used in an automobile or a navigation system used in an automobile.
20. The method of claim 12 , wherein the system is an on-board computer used in an automobile or a navigation system used in an automobile. 21. The method of claim 20 , further comprising receiving information on a driving condition from the on-board computer or the navigation system and determining the state of the user based upon the information on driving condition.