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89 First, it is important to understand that people who are blind Confidence in Decision-Making rarely receive training for every route that they travel or at every intersection they cross. O&M instruction is similar to driver In Chapter 4, the term "utilization" was used to describe a education; people may receive individualized on-the-street pedestrian crossing in a yield or gap. This term objectively training, but they typically receive such extensive training just describes observable behavior rather than making presump- once and then generalize to new areas and update their skills as tions about the pedestrian's ability to detect a yield or crossable they travel and encounter new situations. For individuals who gap. In fact, through the experimental trials in this research it have been blind for many years, formal O&M instruction may became evident that some blind travelers may well be aware have been received decades ago. Depending on an individual's of the presence of, for example, a yielding vehicle (i.e., detec- travel experience and capacity for self-instruction, he or she tion), but may be reluctant for one reason or another to utilize will be more or less knowledgeable about developments in traf- the crossing opportunity. The individual's rationale for non- fic engineering and their implications for non-visual travel. utilization may be tied to past experience (a driver who yielded Just as there is often a need for an educational campaign for but then changed his or her mind), uncertainty (about whether drivers about how to manage roundabouts when roundabouts the vehicle is yielding to the pedestrian or for another reason), are new in an area, there may be a need for an educational cam- or ultimately a lack of confidence in the viability and accuracy paign for pedestrians who are blind or visually impaired when of the detection. roundabouts are installed. Sighted pedestrians have the advantage over blind pedestri- Second, O&M instruction is usually not amenable to class- ans in being able to judge gaps and detect yielding vehicles room instruction, written material, or website content. Most using both visual and auditory information. Lack of access to O&M instruction is provided "on the street" to ensure that visual information places the blind pedestrian at a distinct a blind pedestrian can experience and practice a new set of disadvantage. The distance at which single vehicles can be skills. At roundabouts, this would involve actual experience detected is shorter, perception of direction from which single with roundabout layout and crossings, along with instruction vehicles are coming is less precise, perception of vehicle trajec- by a certified O&M specialist. In addition to providing the tory is very difficult on curving paths, perception of rate of initial instruction and structured experience, the O&M spe- approach (hence time-to-contact) is less precise, the sound of cialist is present to reduce risk (including intervening) and a vehicle that has just passed the crosswalk can mask the sound to provide feedback during the initial stages of learning. The of an approaching vehicle, and it is often difficult to detect the initial instruction may involve the use of tactile (raised line) presence of a yielding vehicle. The presence of multiple vehi- maps of the roundabout. But it is essential to (eventually) cles exacerbates all these difficulties. As a consequence of these experience roundabouts--for example, by walking around difficulties, pedestrians who are blind typically delay crossing and through them and listening to traffic. Ideally, as with longer than pedestrians who are not. This may result in vehic- signalized intersections, this instruction would begin with ular queuing. It may also result in a yielding driver accelerat- relatively simple roundabouts and progress to more com- ing at precisely the time the pedestrian who is blind decides plex ones. Most of the general concepts to be mastered by to begin to cross. This type of behavior was observed during the blind pedestrians are the same as those for sighted pedes- this research. Sighted pedestrians also have the advantage in trians, including, for example, intersection and crosswalk that they can attempt to force yields given the ability to estab- geometry, traffic movements, and crossing strategies. Other lish non-verbal (visual) communication with the approach- concepts have greater relevance to blind pedestrians, such as ing driver(s). Blind pedestrians lack that advantage. the 3 to 4 s of sound masking created by a vehicle that has just From observations, the confidence of pedestrians to make passed the crosswalk in front of (or in back of) a pedestrian. crossing decisions is related to their personal travel skills, expe- Knowledge of these concepts would then be followed up with rience, and willingness to accept risk. It may further be (par- practice, feedback, and more practice. As noted above, the tially) influenced by the opportunities presented, where the most appropriate treatments and strategies for non-visual crossing strategy is a function of traffic patterns during the roundabout crossing remain an open question, and this proj- study. Under low-volume conditions, participants can reason- ect has been a start toward developing such treatments and ably expect that a large gap is likely to occur and may therefore strategies. be more inclined to reject shorter gaps or yields. It is likely As a final caveat on this topic, it is important to note that that varying degrees of confidence contributed to the observed this project has focused on pedestrians who are blind, not inter-participant variability described above. In other words, pedestrians with low vision. Related research (e.g., Geruschat the difference between participants may be a combination of et al. 2006; Hassan, Geruschat, and Turano 2005) has identi- skill (e.g., hearing ability, cognitive ability) and confidence. It is fied challenges experienced by pedestrians with low vision presumed that confidence in decision-making may be improved that are not experienced by pedestrians with normal vision. with repeated exposure and training.