Pedestrian Signal Safety - AAA Foundation for Traffic Safety
Pedestrian Signal Safety - AAA Foundation for Traffic Safety
Pedestrian Signal Safety - AAA Foundation for Traffic Safety
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For younger pedestrians, the mean walking speed (MWS) was 5.00 ft./sec. at traditional intersections<br />
and intersections equipped with PCD signals. As presented in Table F-3, there was no difference in<br />
the walking speed. The median walking speed was 4.90 ft./sec. at traditional intersections and PCD<br />
signals. The 15th-percentile walking speed represents the slower pedestrians at the intersection. The<br />
15th-percentile speed was similar at traditional signals and PCD signals. A walking speed of 4.00<br />
ft./sec. would accommodate the 15th-percentile younger pedestrian at any of these four intersections.<br />
For older pedestrians, MWS at PCD signals was 4.50 ft./sec., slightly faster than the MWS of 4.30<br />
ft./sec. at TPS. As presented in Table F-3, this difference was not significant at the 95-percent<br />
confidence level. The median walking speed was slightly faster at the countdown signal crossings.<br />
The 15th-percentile speed was also slightly faster at countdown signals (3.60 ft./sec.) compared to<br />
traditional signals (3.50 ft./sec.). A walking speed of 4.00 ft./sec. would accommodate the average<br />
older pedestrian at these intersections but would not accommodate the 15th-percentile older<br />
pedestrian.<br />
Table F-3. Significance testing of difference in mean walking speed at traditional and pedestrian<br />
countdown signals <strong>for</strong> two age groups.<br />
Subjects<br />
<strong>Pedestrian</strong>s<br />
under 65<br />
Intersection<br />
type<br />
Mean Standard<br />
deviation<br />
Traditional 5.0 1.05<br />
Countdown 5.0 1.01<br />
<strong>Pedestrian</strong>s Traditional 4.3 1.06<br />
65 and older<br />
Countdown 4.5 1.02<br />
Tcalc<br />
-0.199<br />
-1.272<br />
Outcome<br />
The difference between<br />
means is not significant<br />
at 95 percent.<br />
The difference between<br />
means is not significant<br />
at 95 percent.<br />
Table F-4 presents the results of significance testing of the difference in MWS <strong>for</strong> younger<br />
pedestrians and older pedestrians. As would be expected, the walking speed <strong>for</strong> older pedestrians<br />
was significantly slower than the walking speed <strong>for</strong> younger pedestrians, regardless of the type of<br />
pedestrian signal.<br />
Table F-4. Significance testing of difference in mean walking speed <strong>for</strong> younger pedestrians and older<br />
Intersection<br />
type<br />
Traditional<br />
Countdown<br />
Subjects Mean<br />
<strong>Pedestrian</strong>s<br />
under 65<br />
<strong>Pedestrian</strong>s 65<br />
and older<br />
<strong>Pedestrian</strong>s<br />
under 65<br />
<strong>Pedestrian</strong>s<br />
65 and older<br />
Standard<br />
deviation<br />
5.0 1.05<br />
4.3 1.06<br />
5.0 1.01<br />
4.5 1.02<br />
Tcalc<br />
5.631<br />
5.246<br />
Outcome<br />
The difference<br />
between means is<br />
significant at 95<br />
percent.<br />
The difference<br />
between means is<br />
significant at 95<br />
percent.<br />
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