Methodology for determining level of service categories using attitudinal data

Level of service (LOS) is standard terminology used for characterizing the operational quality of a transportation facility as perceived by the user of that facility. Given that transport systems are commonly designed and operated to maintain a specified LOS, it is a matter of some concern that the measures of effectiveness currently adopted for assessing LOS, as well as the threshold values for partitioning LOS designations, have been established subjectively. A methodology for partitioning LOS designations by using an ordered probit model calibrated with attitudinal data collected by transportation 'users' is described. The application of this methodology is demonstrated by using survey data of bus riders. The basic approach, however, can be applied to all types of transportation facilities.