NAVIGATION DEVICE

PROBLEM TO BE SOLVED: To provide a navigation device capable of enhancing the reliability of an estimated necessary time for arriving at a destination. SOLUTION: The navigation device 1 calculates an estimated necessary time from its current position to the destination, and displays an estimated time of arrival based on the estimated necessary time on a display part 21. When the estimated time of arrival is calculated, the reliability of the estimated time of arrival is calculated. On the occasion of calculating the reliability, a main route and a spare route are acquired, and a travel time by the main route and a travel time by the spare route are compared. Moreover, a correlation coefficient between the change in traffic conditions of the main route and that of the spare route is acquired. In this case, when the difference between the travel time by the main route and the travel time by the spare route is not larger than a predetermined value, the reliability of the estimated time of arrival is calculated so as to be higher, as the correlation coefficient between the changes in traffic conditions is smaller. COPYRIGHT: (C)2011,JPO&INPIT