REGULARITY INDICES FOR EVALUATING TRANSIT PERFORMANCE

Service regularity measures for high-frequency transit are nonexistent at many transit operating agencies. Measures being used or those developed in theory are usually unsatisfactory for one of two reasons: (a) they do not control for the size of headways and therefore cannot be used to compare one route with another, or (b) they are not expressed on a normalized scale (i.e., bounded by 0 and 1). Two measures address these problems: the headway regularity index and passenger wait index. These indices are analyzed and compared both by means of mathematical analysis of data from simulations and by data from actual observation of bus routes in New York City.