Abstract: The invention relates to a method (500) for ascertaining an installation angle (?Install) between a roadway (170) on which a vehicle (100) travels and a detection direction (122) of a measurement or radar sensor (105). The method (500) has a step (510) of reading a plurality of reflection signals (125), each of which represents a measurement or radar beam (120) which has been emitted by a transmission unit (115) of the measurement or radar sensor (105) and each of which has been reflected on a different reflective section (130) of the vehicle (100). The reflection signals (125) have movement information on a movement direction of the vehicle (100) reflective section (130) on which the measurement or radar beam (120) has been reflected, and/or the reflection signals (125) have position information that represents the position (420) of the vehicle (100) reflective section (130) on which the measurement or radar beam (120) has been reflected.