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58 Table 31. Pedestrian delay by treatment. Initial Delay (s) Median Delay (s) Total Delay (s) Treatment Count Avg StdDev Avg StdDev Avg StdDev Flag 2.67 3.37 0.10 0.37 2.72 3.39 350 Half 16.88 19.78 0.69 3.04 17.06 19.70 342 Hawk 7.80 7.86 1.83 6.21 9.63 9.60 224 HiVi 1.86 4.08 0.53 2.35 2.39 4.88 606 InSt 2.09 3.67 0.09 0.86 2.15 3.78 310 Msig 26.35 27.67 0.00 0.00 26.35 27.67 393 OfPa 5.54 9.47 0.10 1.12 5.62 9.59 164 OfPb 5.44 6.61 -- -- 5.44 6.61 254 Refu 5.36 10.20 3.86 11.47 9.22 16.21 512 Grand 8.12 15.46 1.36 6.41 9.01 16.29 3155 Total about 60 percent of crossing pedestrians, while active yellow Only one conflict was observed in the 3,155 crossings eval- devices were activated 28 percent of the time. Also, about uated in this study. That conflict had a car maneuver onto the one-half of the pedestrians at a refuge island had no wait, curb to avoid another car that was stopping for a crossing while 85 to 90 percent of pedestrians at other enhanced pedestrian. treatments had no wait. Of the 67 OfPa pedestrians who had no activation, 27 were Pedestrian Delay at a site where the detector was malfunctioning, 24 were not detected by the system, and 16 were not compliant in using Two types of pedestrian delay were extracted from the the crosswalk. videotapes by recording the difference in time between two events, as follows: Pedestrian-Vehicle Conflicts For initial delay, the difference in time between points A A pedestrian-vehicle conflict was counted if either a pedes- and B in Figure 21, recorded as the variable initial delay; trian or a vehicle acted to avoid a pedestrian-vehicle collision. and Evasive actions by the pedestrian included rushing to com- For median delay, the difference in time between points C plete a crossing or aborting a started crossing. Evasive actions and D in Figure 21, recorded as the variable median delay. by the vehicle included sudden swerving, lane changing, or braking. Each pedestrian-vehicle conflict was coded into one Table 31 summarizes the initial, median, and total pedes- of the categories shown in Figure 20. In addition the follow- trian delay by treatment. Initial pedestrian delay is highest at ing location for the conflict was recorded: sites with red treatments, followed by beacons (passive and active) and refuge islands. Sites with flags, high-visibility 1. Conflict with the first direction of main street vehicle traffic, markings, and in-street signs all had an average initial pedes- 2. Conflict with the second direction of main street vehicle trian delay lower than 3 seconds. Median pedestrian delay for traffic, all sites was very low, except for those with refuge islands. Sites 3. Conflict with left-turning side street vehicle traffic, or with HAWK signals were the only other sites to have an aver- 4. Conflict with right-turning side street vehicle traffic. age median pedestrian delay higher than 1 second.