Abstract: An occupant discrimination system incorporates a position sensor for measuring the distance from a fixed structure within the vehicle to a first surface of an occupant or object on a vehicle seat, and a seat weight sensor for measuring the weight of the occupant or object. The position sensor generates a plurality of signal components that are combined with the weight and vehicle speed related measurements so as to form a signal space, from which a plurality of measures are calculated. A plurality of seat occupancy scenarios are defined and the likelihood of each seat occupancy scenario is functionally related to the plurality of measures. For a given measure state, the likelihood of each of the seat occupancy scenarios is calculated, and the most likely scenario is used to govern the control of a safety restraint system.