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OCR for page 127
127 Exhibit 42. O&M interventions for RCW. O&M Interventions RCW Crosswalk Pre Frequency # of Crossings Percent Entry 3 144 2.1% Exit 5 144 3.5% Overall 8 288 2.8% Post Entry 0 104 0.0% Exit 0 104 0.0% Overall 0 208 0.0% Exhibit 43. O&M intervention rate by subject and Exhibit 44. Summary of crossing performance time of day. pre and post RCW installation. RCW Performance Measure Pre Post 20.0% Yield Availability* 25.2% 49.1% PRE Gap Availability* 23.7% 30.7% 15.0% Yield Utilization* 61.7% 94.0% O&M Interventions POST Gap Utilization* 81.1% 94.5% 10.0% 85th percentile Delay (s) 31.0 13.4 O&M Interventions 2.8% 0.0% 5.0% *Average of Near and Far Lane 0.0% 1 3 6 9 11 16 4 7 10 12 14 17 2 5 8 13 15 18 may have altered driver behavior in a way that made it easier -5.0% 9:00am 11:30am 3:30pm to detect crossing opportunities (e.g., yielding more abruptly and closer to the crosswalk). A learning effect by pedestrians is Subject unlikely because the single-lane roundabout comparison site did not show improvement in behavior. Exhibit 44 presents a summary of the pre and post crossing performance at the raised crosswalk. RCW Summary In summary, the RCW seemed to have an impact on the In summary, the installation of the raised crosswalk signal availability of crossing opportunities in the form of yields and resulted in a large reduction of both delay and interventions further increased the rate of opportunity utilization for both for all study participants. The relative difference between pre yields and gaps. The treatment therefore affects both driver and post studies was greatest for participants that experienced behavior (yield availability) and pedestrian behavior (utiliza- high delays in the pre condition, as the RCW created a more tion). The effect on the behavioral parameters was large enough uniform distribution of delay across participants. The RCW to significantly impact the bottom line in the form of greatly further reduced the overall number of events, with much fewer reduced delay and the reduction of O&M interventions to zero. rejected events. As more drivers yield, the relative frequency While some pedestrians still encountered some high delay of gaps encountered decreases. time in the post treatment installation, the overall effect was a The installation of the RCW further seemed to enhance the reduction in the delay estimate itself as well as in the range and efficiency with which crossing opportunities were utilized. variability of the estimate. The biggest impact was notable for The higher utilization rates can potentially be explained by pedestrians who had high delays in the pre condition and the hypothesis that pedestrians felt more confident with the whose post-treatment performance was within the range of RCW in place and its effect on drivers. Alternatively, the RCW that of more comfortable and experienced travelers.