Before-After Evaluation of FTMS Effectiveness

This paper demonstrated the possibilities for conducting before-after evaluation of a new freeway traffic management system (FTMS) using only data from the inductive loop detectors. Using those data, regression models have been constructed for the amount of congested travel as a function of total travel, weather conditions, and number of incidents. These models are then compared for 2 months of data before and 2 months of data after FTMS implementation. the analysis is necessarily limited because of the size of the data set, which is 41 days in each of the before and after periods. the models show that the FTMS had a positive effect. The best estimate is that the FTMS has been associated with reductions of between 6% and 10%, on average, in the amount of congested travel on the system, all else being equal.