TRAVEL TIME PREDICTION METHOD, TRAVEL TIME PREDICTION DEVICE, AND PROGRAM

A computer refers to a storage unit that stores plural pieces of observation data formed by observing, at a plurality of timings, a travel time taken for a vehicle to pass through a road section. The computer then obtains a first statistical value of the travel time at a first time of a prediction target day on the basis of two or more of the plural pieces of observation data for the road section. The computer further obtains a second statistical value of the travel time at a second time that is later than the first time. The computer then calculates a prediction value of the travel time for the road section at the second time on the basis of the first statistical value, the second statistical value, and the travel time for the road section observed at the first time. In this case, the computer calculates the prediction value such that a difference between the second statistical value and the prediction value of the travel time for the road section at the second time is smaller than a difference between the first statistical value and the travel time for the road section observed at the first time.