Developing an "intuitive understanding" of crossing time
It took me more than a decade to realize that most people have difficulty recognizing Situations of Uncertainty unless they have an "intuitive understanding" of their crossing time -- a functional, gut-level cognitive understanding of the passing of time that they need to cross.
This intuitive understanding of crossing time also helps students who are learning to judge gaps in traffic (covered in Section 4)
and I've discovered that it is helpful for learning to cross signalized intersections as well (if you want to see an example, you can click here).
So before teaching students to recognize Situations of Uncertainty, I help them develop that untuitive understanding of their crossing time.
I was amazed that students do not develop this "intuitive understanding" of crossing time by crossing the street, even if you tell them how many seconds the crossing time is!
Isn't that astonishing?
The story of how I discovered that is shared in Vignette #1, and
my observations were supported with research by Dr. Shirin Hassan.
However, students can develop this intuitive understanding with the following exercise, which normally takes only about 5 minutes.
When / how to apply this skill:
Students should develop an intuitive understanding of their crossing time for streets of various widths.
With this skill, they'll understand (on a "gut" level) how much time they need to cross any street, once they determine how wide it is.
They should realize that they may naturally walk faster across streets that seem dangerous than they do at quiet residential streets.
Some students seem to retain this skill indefinitely, but some need to renew it.
I've found that if students have trouble in subsequent lessons comparing warning time of approaching vehicles with their crossing time or recognizing Situations of Uncertainty, it is helpful for them to review their intuitive understanding of crossing time for streets of that width.
Exercise for Developing Intutitive Understanding of crossing time
This is the procedure I use to help students develop an intuitive understanding of their crossing time:
Once the student knows how wide the street is and you have timed the student crossing it (or crossing the equivalent distance, such as in the parking lot shown in the photos to the right), ask the student to imagine crossing the street, beginning when you start a timer.
Report when the student would have completed the crossing, based on the student's actual crossing times.
That is, when the time that the student needs to cross has passed, tell the student that is when s/he would have reached the other side.
For wide crossings, it often helps if you report to the student when she would have reached the second lane, the third lane, the middle of the street, the last lane, etc.
Next, ask the student to imagine crossing the street, reporting to you when she starts her imaginary crossing and when she thinks she would have reached the other side.
Start a stopwatch when the student reports that the imaginary crossing has begun, and stop the watch when the student predicts she would have reached the other side
Tell the student whether she was accurate.
The exercise continues until the student can consistently measure the time needed to cross (give or take a second).
This may be reversed and the instructor asks the student to imagine starting to cross, then interrupts and ask the student to report where in the crossing she would be at that time.
The ability to determine this will be helpful later, when the student is listening/(looking) for approaching vehicles -- the student can predict where in the crosswalk she would have been if she had started to cross just before detecting an approaching vehicle and the driver hadn't slowed down for her.
Some excerpts of this training are in the video to the right.
NOTE: When students are learning to judge the time needed to cross, they should not be simply counting the seconds, just as they should not be counting steps when they are learning to judge distances.
Although some students enjoy the challenge of accurately measuring the passage of time and seconds (and doing so can be a fun additional exercise for these students), it is more important that they develop an intuitive understanding of the passing of time during their crossings.
This will allow them to make crossing judgments naturally and spontaneously, as most people do, rather than having to concentrate on counting or timing.