DRIVER ASSISTANCE SYSTEM, VEHICLE, RECORDING MEDIUM RECORDING COMPUTER PROGRAM, AND DRIVER ASSISTANCE METHOD

Provided is a driver assistance system or the like that makes it possible to assist a driver in taking a driving behavior more effectively by stimulating the auditory sense of the driver without executing complicated processing. A management server repeatedly executes a behavior data acquisition process including acquiring behavior data of the driver based on a sound effect and a sound effect output control process including outputting the sound effect into the vehicle while changing an output condition for outputting the sound effect into the vehicle . When the result of these processes satisfies a setting condition set in advance, the management server executes an identification process including identifying the output condition corresponding to the result as an optimal output condition.