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123 Exhibit 33. Availability and utilization statistics 4. Falsely Accepted Non-Crossable Event: Pedestrian "GO" for pre condition, RCW. in a non-crossable/unsafe situation. 5. Inconclusive Event: Pedestrian "GO" in a forced yield Pre (n = 686) Near Lane Far Lane condition. Availability Statistics P(Y_Enc) 26.7% 23.8% The first four categories correspond to a classical 2x2 event P(CG_Enc) 25.5% 21.9% matrix that relates the real-world condition to the pedestrian Utilization Statistics response. The fifth category was introduced, since it is "incon- P(GO|Y) 54.6% 68.7% clusive" whether a forced yield should be interpreted as an P(GO|CG) 78.9% 83.3% acceptable crossing strategy or not. Exhibit 34 summarizes the event classifications for the pre study at the RCW. Exhibit 34 suggests that for the total of 686 events, 23.8% of Of a total of 503 encountered gaps in the near lane, 175 crossings were correct utilizations of crossing opportunities were crossable (34.8%), and 78.9% of these crossable gaps and 58.6% of events were correctly rejected events. Only 6.0% were utilized by the pedestrian. The likelihood of encoun- were classified as missed opportunities and inefficient behav- tering a crossable gap from the 686 total events was 25.5%. ior, and 1.3% fell into the "unsafe" category. Also, 10.3% of Of the 37 non-utilized crossable gaps, 30 had non-crossable events were associated with a forced yield and were labeled as gaps in the far lane. The nearfar lane evaluation makes it inconclusive. Note that any O&M interventions were removed evident that both need to be considered in the evaluation of from the dataset prior to analysis (discussed separately) and so pedestrian behavior. Exhibit 33 shows a summary of the cross- none of these forced yields resulted in a truly dangerous situ- ing opportunity availability and utilization statistics for the ation. However, in the absence of pedestrian and/or driver pre condition. action, a forced yield can result in a collision. The exhibit shows a relatively low rate of yield and crossable gap occurrence in both lanes, explaining the large portion of Posttest Pedestrian Behavior pedestrianvehicle events that did not result in a crossing. at the RCW Further, the rate of yield utilization is only 54.6% and 68.7% in the near and far lane, suggesting a lot of pedestrian uncer- The installation of the raised crosswalk was expected to tainty. Gap utilization is somewhat higher, at around 80%. assist pedestrians by encouraging more drivers to yield and by The results in Exhibit 33 can further be interpreted as events generally slowing down the conflicting traffic in the vicinity of that are potential crossing opportunities (in the form of yields the crosswalk. Since the treatment does not involve any form and crossable gaps) and those that correspond to non-crossable of signalization, the same nearfar analysis framework was gaps. Using this stratification, every cell in Exhibit 33 can be applied to the post dataset. Exhibit 35 plots the near- and far- categorized as to whether the pedestrian correctly interpreted lane events (same as pre analysis) for the RCW installation. an event (for example utilized a crossable gap in both lanes) Exhibit 35 shows that the probability of encountering a yield or not. Applying this framework to every cell, a total of five after the RCW installation increased from 26.7% to 51.3% in event outcome categories emerge: the near lane. Further, the rate of yield utilization increased from 54.6% to 92.0%. The presence of the RCW may have led 1. Correctly Accepted Crossing Opportunity: Pedestrian to a modified driver behavior that made it easier for pedestri- "GO" in a crossable/safe situation. ans to detect the yield. In the near lane, 13.8% of yields were 2. Falsely Rejected Crossing Opportunity: Pedestrian forced by pedestrians, which is slightly less than the 16.4% in "NoGO" in a crossable/safe situation. the pre condition. 3. Correctly Rejected Non-Crossable Event: Pedestrian In the post data collection, pedestrians encountered 131 gaps, "NoGO" in a non-crossable/unsafe situation. and 80 of those were crossable. The likelihood of encountering Exhibit 34. Summary of pedestrian behavior, pre condition, RCW. Pedestrian Crosswalk Condition Decision Crossable/Safe Non-Cross./Unsafe Inconclusive GO 163 23.8% 9 1.3% 71 10.3% NoGO 41 6.0% 402 58.6%