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55 16 14 12 10 Gap (s) 8 6 Observed 85th Percentile Accepted Gap 4 Adequate Gap at 3.0 ft/s (0.9 m/s) Adequate Gap at 3.5 ft/s (1.1 m/s) 2 Adequate Gap at 4.0 ft/s (1.2 m/s) 0 20 25 30 35 40 45 50 55 Crossing Distance (ft) (NOTE: 1 ft = 0.305 m) Figure 29. Comparison of trends for observed 85th percentile accepted gaps and calculated critical gaps for walking speeds of 3.0, 3.5, and 4.0 ft/s (0.9, 1.05, and 1.2 m/s). pedestrians in this study were not consistently accepting gaps or bicycles) are excluded, the percentage of pedestrians who exceeding the calculated critical gap, and the 3.5 ft/s (1.1 m/s) ran or walk/ran becomes 18 percent. For the entire database design criterion appears sufficient for the pedestrians available from this study on pedestrian crossing behavior, observed. about 14 percent of the pedestrians who did not use assis- tance either ran or walk/ran through the crossing. In other words, a small but notably larger percentage of transit Transit Rider Walking Behavior pedestrians ran or walk/ran as compared with the general Before Departing population. Whether or not a pedestrian was a transit rider was noted The time that each boarding pedestrian waited was deter- as part of the data reduction effects for those sites where a mined as the difference between arrival of the pedestrian at transit stop was within view of the cameras. A total of 878 the transit stop and the arrival of the bus. The relationship pedestrians were observed at sites when a transit stop was in between crossing speed and the wait time is shown in Figure camera view with 6 percent (53 pedestrians) being transit rid- 30. Pedestrians with wait times less than 2 minutes showed ers who boarded a bus and 5 percent (43 pedestrians) being the largest range of crossing speeds with the three fastest transit riders who alighted from a bus. Of the 53 pedestrians crossing speeds associated with wait times of less than 0.5 who boarded a bus, the distribution of crossing behavior is minutes. These pedestrians could be examples of the situation listed in Table 25. when pedestrians will run because they see an approaching About 17 percent of the boarding pedestrians ran or bus. As a contrast to that situation, some of the pedestrians walk/ran through the major roadway crossing before board- with wait times on the order of 10 minutes also ran or ing. When the pedestrians who used assistance (e.g., skates walk/ran in their crossing. Figure 30 shows a nonlinear relationship between crossing speed and rider wait time with an increasing trend in cross- Table 25. Crossing behavior prior to boarding transit. ing speed as wait time increases. Researchers attempted to find a statistical relationship. Several transformations were Number of Percent Pedestrian Crossing Behavior Pedestrians (%) (Based on Technician's Judgment) tried on both crossing speed and rider wait time. The no 2 4 Assisted (had skates, bicycles, etc.) transformation on crossing speed and the log transformation 6 11 Ran and walked 3 6 Ran on rider wait time led to the smallest root mean square error 42 79 Walked (RMSE) when fitting was done by the least squares method. 53 100 TOTAL Table 26 contains the estimated coefficients and the corre-