Patent ID: 7983837

Claim:
A display method for a car navigation system which displays a position and proceeding direction of a user's car on a road map and displays a guide route on the road map, the display method overlappingly displaying a graphic at a position on the road map corresponding to traffic jam statistical information, wherein an area surrounded by said graphic depends on the traffic jam statistical information and a statistical reliability of the traffic jam statistical information, wherein said statistical reliability is a rank classification depending on an evaluation of a repeatability of the traffic jam information, based on a standard deviation of said traffic jam information wherein the standard deviation is obtained by; a first step of removing a day of data in advance as abnormal data when a predetermined time or more in the day indicate a traffic jam; a second step of removing data having a large deviation in advance as abnormal data when traffic jam information in a same time interval is compared for a plurality of days; and a step of calculating each standard deviation of the traffic jam statistical information at a predetermined location where the abnormal data is removed by the first and second step, and wherein said graphic has a perimeter that changes based on said statistical reliability.