Impact of Freeway Service Patrols on Incident Clearance Duration: Case Study of Florida's Road Rangers

摘要

Florida's Road Rangers monitor the freeways for incidents to minimize incident clearance duration. The objective of this study was to evaluate the extent to which Road Rangers reduce incident clearance duration. Because incident clearance duration distributions are often right-skewed, the study applied quantile regression to relate incident clearance duration to influencing factors. Data skewed to the right are usually a result of lower bounds in a data set being extremely low relative to the rest of the data. Data from 28,000 incidents that occurred on freeways in Jacksonville, Florida, for the years 2014-2017 were analyzed. Of the factors analyzed, crash events, incident severity, shoulder blockage, weekends, nighttime, number of responding agencies, and towing were found to significantly increase incident clearance durations. Road Rangers were found to reduce incident clearance duration by 25.3%. In other words, shorter incident clearance durations were observed when Road Rangers responded to incidents compared to other agencies. The results of this study can, in general, provide researchers and practitioners with an effective way of evaluating the mobility benefits of the Road Ranger program.