Information providing method and information providing system

1. An information providing method in an information providing system configured to communicate with an in-vehicle device installed in a vehicle via roadside antennas, the information providing method comprising:

acquiring pieces of speed information of the vehicle in association with identification information of the in-vehicle device from the in-vehicle device via the roadside antennas, each of the pieces of speed information having been stored in the in-vehicle device each time the vehicle moves a prescribed distance before the vehicle passes by the roadside antennas; and

causing an information display device to display evaluation information in association with the identification information, the evaluation information indicating a frequency of occurrence of sudden acceleration events or sudden deceleration events of the vehicle, the frequency of occurrence being obtained from a proportion of differences between calculation values outside a threshold range, the calculation values being calculated on a basis of the pieces of speed information in a prescribed period corresponding to the pieces of speed information stored in the in-vehicle device, the evaluation information indicating that a driver of the vehicle has a tendency of the sudden acceleration events or the sudden deceleration events when the proportion is higher than or equal to a prescribed value,

wherein the in-vehicle device transmits the pieces of speed information of the vehicle and the identification information of the in-vehicle device to the roadside antennas, whereupon the information providing system acquires the pieces of speed information of the vehicle and the identification information of the in-vehicle device from the roadside antennas.

2. The information providing method according to claim 1 ,

wherein the calculation values are speed differences of the vehicle or acceleration values calculated on a basis of the speed differences of the vehicle.

3. The information providing method according to claim 2 ,

wherein the speed differences or the acceleration values are calculated on a basis of differences between adjacent pieces of speed information in a time series.

4. The information providing method according to claim 1 ,

wherein the frequency of occurrence of sudden acceleration events or sudden deceleration events is determined to be high if the proportion is higher than or equal to a threshold proportion.

5. The information providing method according to claim 1 ,

wherein the evaluation information is plotted on a chart having an axis representing a proportion of sudden acceleration events and an axis representing a proportion of sudden deceleration events, and

wherein the causing the information display device to display the evaluation information comprises displaying pieces of evaluation information in association with a plurality of different pieces of identification information, respectively, as correlation data constituting the chart.

6. The information providing method according to claim 5 ,

wherein the correlation data is displayed on the information display device with an indication showing that the pieces of evaluation information contained in a first region are identifiable, the first region being where the proportion of sudden acceleration events and the proportion of sudden deceleration events are both large.

7. The information providing method according to claim 5 ,

wherein the correlation data is displayed on the information display device with an indication showing that the pieces of evaluation information contained in a second region are identifiable, the second region being where the proportion of sudden acceleration events and the proportion of sudden deceleration events are equal to or smaller than respective thresholds.

8. The information providing method according to claim 1 , further comprising:

acquiring position information or date and time information at a time of acquisition of the pieces of speed information; and

selecting at least one acceleration value for calculating the threshold range on a basis of the position information or the date and time information.

9. The information providing method according to claim 1 , further comprising:

acquiring position information or date and time information at a time of acquisition of the pieces of speed information; and

setting the threshold range on a basis of sets of the calculation values relating to respective different vehicles having the position information or the date and time information in common.

10. The information providing method according to claim 1 ,

wherein at least part of the calculation values outside a prescribed range are excluded as abnormal values.

11. The information providing method according to claim 1 ,

wherein the pieces of speed information are accumulated in the in-vehicle device through sampling by detection of the vehicle moving the prescribed distance each time on a basis of satellite positioning signals acquired from artificial satellites.

12. An information providing system configured to communicate with an in-vehicle device installed in a vehicle via roadside antennas and communicate with a device installed in the vehicle via a network, and configured to store, in a storage, pieces of speed information of the vehicle in association with identification information of the in-vehicle device received from the in-vehicle device via the roadside antennas, each of the pieces of speed information having been stored in the in-vehicle device each time the vehicle moves a prescribed distance before the vehicle passes by the roadside antennas, the information providing system comprising:

one or more processors; and

one or more memories having instructions, when executed by the one or more processors, to cause the information providing system to perform operations, the operations comprising:

retrieving the pieces of speed information of the vehicle in association with the identification information from the storage; and

transmitting evaluation information to the device via the network to cause the device to display the evaluation information, the evaluation information indicating a frequency of occurrence of sudden acceleration events or sudden deceleration events of the vehicle, the frequency of occurrence being obtained from a proportion of differences between calculation values outside a threshold range, the calculation values being calculated on a basis of the pieces of speed information in a prescribed period corresponding to the pieces of speed information stored in the in-vehicle device, the evaluation information indicating that a driver of the vehicle has a tendency of the sudden acceleration events or the sudden deceleration events when the proportion is higher than or equal to a prescribed value,

wherein the in-vehicle device transmits the pieces of speed information of the vehicle and the identification information of the in-vehicle device to the roadside antennas, whereupon the information providing system acquires the pieces of speed information of the vehicle and the identification information of the in-vehicle device from the roadside antennas.

13. An information providing system configured to communicate with an in-vehicle device installed in a vehicle via roadside antennas and store, in a storage, pieces of speed information of the vehicle in association with identification information of the in-vehicle device from the in-vehicle device via the roadside antennas, each of the pieces of speed information having been stored in the in-vehicle device each time the vehicle moves a prescribed distance before the vehicle passes by the roadside antennas, the information providing system comprising:

one or more processors; and

one or more memories having instructions, when executed by the one or more processors, to cause the information providing system to perform operations, the operations comprising:

retrieving the pieces of speed information of the vehicle in association with the identification information of the in-vehicle device from the storage; and

causing an information display device to display evaluation information in association with the identification information, the evaluation information indicating a frequency of occurrence of sudden acceleration events or sudden deceleration events of the vehicle, the frequency of occurrence being obtained from a proportion of differences between calculation values outside a threshold range, the calculation values being calculated on a basis of the pieces of speed information in a prescribed period corresponding to the pieces of speed information stored in the in-vehicle device, the evaluation information indicating that a driver of the vehicle has a tendency of the sudden acceleration events or the sudden deceleration events when the proportion is higher than or equal to a prescribed value,

wherein the in-vehicle device transmits the pieces of speed information of the vehicle and the identification information of the in-vehicle device to the roadside antennas, whereupon the information providing system acquires the pieces of speed information of the vehicle and the identification information of the in-vehicle device from the roadside antennas.