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Pedestrian Signal Safety - AAA Foundation for Traffic Safety

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For younger pedestrians, the mean walking speed (MWS) was 4.80 feet/second (ft./sec.) at traditional<br />

intersections and 5.30 ft./sec. at intersections equipped with countdown signals. The 15th-percentile<br />

walking speed represents the slower pedestrians at the intersection. The 15th-percentile speed was<br />

4.10 ft./sec. at traditional signals and 4.70 ft./sec. at PCD signals. A walking speed of 4.00 ft./sec.<br />

would accommodate the 15th-percentile younger pedestrian at any of these four intersections.<br />

For older pedestrians, MWS was 4.20 ft./sec. at traditional intersections and 4.80 ft./sec. at<br />

intersections equipped with countdown signals. The 15th-percentile speed was 3.60 ft./sec.<br />

at traditional signals and 4.00 ft./sec. at PCD signals. A walking speed of 4.00 ft./sec. would<br />

accommodate the 15th-percentile older pedestrian at the PCD intersection but not at the traditional<br />

intersection.<br />

The significance testing <strong>for</strong> MWS is presented in Table H-3. There was a significant difference in<br />

MWS at traditional and PCD intersections <strong>for</strong> both younger and older pedestrians.<br />

Table H-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 />

<strong>Pedestrian</strong>s<br />

65 and older<br />

Intersection<br />

type<br />

Mean Standard<br />

deviation Tcalc Outcome<br />

Traditional 4.8 0.73<br />

Countdown 5.3 0.73<br />

9.66<br />

Traditional 4.2 0.71 6.84<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 />

Table H-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 H-4. Significance testing of difference in mean walking speed <strong>for</strong> younger pedestrians and<br />

older pedestrians <strong>for</strong> two types of pedestrian signal.<br />

Intersection<br />

type<br />

Traditional<br />

Countdown<br />

Subjects Mean Standard<br />

deviation Tcalc Outcome<br />

<strong>Pedestrian</strong>s<br />

under 65<br />

<strong>Pedestrian</strong>s<br />

65 and older<br />

4.8<br />

4.2<br />

0.73<br />

0.71<br />

7.83<br />

The difference<br />

between means is<br />

significant at 95<br />

percent.<br />

<strong>Pedestrian</strong>s<br />

under 65<br />

<strong>Pedestrian</strong>s<br />

65 and older<br />

5.3<br />

4.8<br />

0.73<br />

0.81<br />

6.43<br />

The difference<br />

between means is<br />

significant at 95<br />

percent.<br />

215

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