Lane change assist system, lane change assist device, and lane change assist method

A lane change assist system comprising:

• a first terminal in a first vehicle, a second terminal in a second vehicle, and a third terminal in a third vehicle;
• and
• a lane change assist device configured to be able to communicate with the first terminal, the second terminal, and the third terminal and to manage the economic values held by the user of the first terminal or the first vehicle, the user of the second terminal or the second vehicle, and the user of the third terminal or the third vehicle, wherein
• the lane change assist device is configured to decrease the economic value held by the user of the first terminal or the first vehicle and increase the economic value held by the user of the third terminal or the third vehicle when the first vehicle driving on the first driving lane cuts into between the second vehicle and the third vehicle driving on a second driving lane adjoining the first driving lane and changes lanes to the front of the third vehicle driving at the rear of the second vehicle.