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50 There may be some evidence that participant decision mak- cross here safely on a scale of 1 to 5, with 1 being not at all and ing in terms of risk taking improved; however, this claim is 5 very confident?") was 4.40 in Charlotte, 4.41 for the Golden not supported by the other performance statistics (mostly the pretest, and 4.46 for the Golden posttest. While Golden par- utilization rates). Since interventions are very rare events, it ticipants seemed more confident to the research team at the is likely that this apparent reduction is the result of random single-lane location in the posttest round, that impression variability in this measure. was not supported by the participant survey results. At the PS-RAL and DAV-CLT single-lane crossings, the On the question "Would you use these crossings if they queues that formed behind the yielding driver were safely were on the most direct route home from work?" (slightly dif- contained behind the stopped car. However, a wide exit lane ferent wording in Charlotte), nine participants said yes and at the Golden single-lane roundabout caused some drivers to one said "no, would find another way" in Charlotte; for the overtake the stopped car, creating a multiple-threat situation Golden pretest 15 said yes, one no, one "maybe, depending for the pedestrian. This behavior was also observed in relation on time of day," and one did not answer that question; and in to buses stopped at a downstream bus stop at this exit-lane the Golden posttest, all 12 said yes, including one who had crossing. While the intervention rate at this roundabout was said no in the Golden pretest. low, this particular aspect of driver behavior causes concern In Charlotte, participants were asked about yielding vehicles for pedestrian safety. The issue of multiple-threat situations, and their reasons for crossing or not crossing when vehicles where a near-lane yielding vehicle blocks the visual (and audi- had yielded. (This question was not separated from the ques- tory) connection between the pedestrian and a far-lane driver, tion about cues used for crossing in the Golden debriefing was hypothesized for two-lane roundabouts. Due to the wide questionnaires.) Most comments indicated that participants lane widths, it also proved a concern at this exit-lane crossing. found it difficult to decide if the drivers were yielding for them No multiple-threat events were observed at the entry leg. or something else (possibly other vehicles at entry lanes) and The findings from the GOL-PRE and GOL-POST studies were concerned about how long drivers would stay stopped. first and foremost give confidence that any observed treat- Some stated that they waited for a person to actually roll down ment effect at the nearby two-lane roundabout was largely the window and talk to them before they would cross in front unrelated to a participant learning effect. Since the same par- of a yielding vehicle. Some said they were unaware that a vehi- ticipants performed the studies at both sites, the lack of an cle had yielded until after they had completed their crossing effect at this single-lane location supports the notion that the and heard the vehicle move behind them. In other words, they tested two-lane treatments indeed improved the crossing task, had not heard the vehicle at all and thought they were crossing as is discussed below. in a gap in traffic. In comparison with the other single-lane roundabouts, the In response to a question about modifications that might GOL-PRE/POST site exhibits similar performance to the PS- be needed to improve accessibility, the main concerns were RAL site in the accessibility criteria of crossing opportunities, with wayfinding, although a couple of participants suggested opportunity utilization, and delay. However, its safety per- a signal of some sort to indicate when vehicles had yielded. formance is more similar to the DAV-CLT site, with a gener- Several said the roundabout was pretty accessible as is, or that ally low intervention rate. Overall, this site appears to be the it didn't need anything. The Charlotte participant who said most accessible of the three tested single-lane roundabouts she wouldn't use the crossings stated that she was still con- with low delay and risk. fused about finding the crosswalks and lining up correctly and not so concerned about the traffic and crossing. Golden Participant Feedback participants commented on the narrow splitter island and the Following each of the single-lane roundabout studies, par- fact that no detectable warnings were installed. These geo- ticipants were asked a series of questions about their percep- metric features raised concerns about being sure they stopped tion of the crossing and the level of comfort in their crossing on the island before crossing the next lane of traffic. decisions. Participant feedback from the Raleigh roundabout was not available to the research team. The blank survey forms Impact on Vehicular Traffic for the Charlotte and Golden roundabouts are provided in Appendix G. Since no treatments were tested at the single-lane round- Feedback from the Charlotte and Golden single-lane round- abouts, any impact on vehicle traffic is strictly attributable to abouts indicated that participants generally felt comfortable the normal interaction between pedestrians and drivers. with the crossing task at those locations in each round of While no formal delay studies were performed at these loca- testing. The average of the responses on the confidence ques- tions, the research team noted no significant queuing impacts tion ("How would you rate your confidence in your ability to that resulted from the presence of the blind study participants.