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<br />
<br />Table 7. Pedestrian crashes and volumes for marked and unmarked crosswalks.
<br />Lanes Median Traffic Volume Type Sites Pedestrian
<br />Volume
<br />Crashes Avg.
<br />Yrs.*
<br />Two None < 8,000 Marked
<br />Unmarked
<br />248
<br />252
<br />110,697
<br />67,793
<br />15
<br />10
<br />4.85
<br />4.86
<br />Two None > 8,000 Marked
<br />Unmarked
<br />199
<br />200
<br />62,530
<br />35,957
<br />19
<br />13
<br />4.74
<br />4.75
<br />Multi No raised
<br />median
<br />< 3,000 Marked
<br />Unmarked
<br />10
<br />13
<br />1,446
<br />998
<br />0
<br />0
<br />3.80
<br />4.08
<br />Multi No raised
<br />median
<br />3,000–6,000 Marked
<br />Unmarked
<br />33
<br />29
<br />6,382
<br />3,298
<br />3
<br />1
<br />4.58
<br />4.48
<br />Multi No raised
<br />median
<br />6,000–9,000 Marked
<br />Unmarked
<br />37
<br />39
<br />20,608
<br />5,397
<br />0
<br />2
<br />4.43
<br />4.49
<br />Multi No raised
<br />median
<br />9,000–12,000 Marked
<br />Unmarked
<br />47
<br />52
<br />23,024
<br />6,721
<br />12
<br />4
<br />4.87
<br />4.90
<br />Multi No raised
<br />median
<br />12,000–15,000 Marked
<br />Unmarked
<br />76
<br />73
<br />20,719
<br />7,825
<br />23
<br />2
<br />4.82
<br />4.79
<br />Multi No raised
<br />median
<br />> 15,000 Marked
<br />Unmarked
<br />210
<br />207
<br />39,835
<br />12,700
<br />91
<br />6
<br />4.57
<br />4.57
<br />Multi With raised
<br />median
<br />< 9,000 Marked
<br />Unmarked
<br />30
<br />23
<br />5,024
<br />1,182
<br />2
<br />0
<br />4.87
<br />4.83
<br />Multi With raised
<br />median
<br />9000–15,000 Marked
<br />Unmarked
<br />22
<br />25
<br />4,924
<br />1,671
<br />3
<br />0
<br />4.18
<br />4.28
<br />Multi With raised
<br />median
<br />> 15,000 Marked
<br />Unmarked
<br />88
<br />87
<br />16,659
<br />11,276
<br />20
<br />3
<br />4.60
<br />4.56
<br />*Avg. Yrs. = Average number of years of crash data per site.
<br />
<br />Then conditional on total crashes, Ni in category i, expected marked crosswalk crashes under the
<br />hypothesis of equal safety were estimated as Âmi = Ni pmi. The probability under this hypothesis of
<br />observing as many or more crashes in marked crosswalks as actually occurred was obtained from the
<br />binomial distribution with parameters pi and Ni. Table 8 lists these quantities for the various crosswalk
<br />categories.
<br />
<br />The results in table 8 suggest that on two-lane roads, multilane roads without raised medians and traffic
<br />volumes below 12,000 ADT, and multilane roads having raised medians and traffic volumes below
<br />15,000 ADT, the hypothesis of equal safety for marked and unmarked crosswalks cannot be rejected.
<br />
<br />In other words, there was no significant effect of marked versus unmarked crosswalks on pedestrian
<br />crashes under the following conditions:
<br />
<br />• Two-lane roads.
<br />• Multilane roads without raised medians and with ADTs below 12,000.
<br />• Multilane roads with raised medians and with ADTs below 15,000.
<br />
<br />For multilane roads with ADTs above these values, there was a significant increase in pedestrian crashes
<br />on roads with marked crosswalks, compared to roads with unmarked crosswalks (after controlling for
<br />traffic ADT and pedestrian ADT).
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