An Analysis of the Effects of Crash Factors and Precrash Actions on Side Impact Crashes at Unsignalized Intersections
Table 8
Behavioral pathway analysis of four-way intersections with direct and indirect marginal effects.
Variable (X)
Direct ME on Y2
for Y1 RSS
for Y1 FYSS
ME on Y1 RSS
ME on Y1 FYSS
for Y2
ME of Y1 RSS on Y2
ME of Y1 FYSS on Y2
Indirect ME on Y2 through RSS
Indirect ME on Y2 through FYSS
Total ME on Y2
Urban
Yes
−12.01%
31.75
17.00
2.03
0.00
0.00%
−12.01%
Crash location (base: other crash locations)
Open country
6.45%
31.75
17.00
2.03
0.00
0.00%
6.45%
Residential area
−5.25%
10.51
2.61%
31.75
17.00
2.03
3.06
0.00%
−2.19%
Shopping center
−4.67%
31.75
17.00
2.03
0.00
0.00%
−4.67%
Roadway condition
Dry
31.75
17.00
2.03
0.00
0.00%
0.00%
Wet
31.75
17.00
2.03
0.00
0.00%
0.00%
Lighting condition
Daylight
51.68
4.89%
31.75
17.00
2.03
0.00
2.70%
2.70%
Dark without lighting
14.37
0.37%
31.75
17.00
2.03
2.62
0.00%
2.62%
Dark with lighting
31.75
17.00
2.03
0.00
0.00%
0.00%
Roadway geometry (base: curved roadway)
Straight level road
3.24%
12.26
61.44
12.26%
17.96%
31.75
17.00
2.03
8.06
7.31%
18.61%
Straight road with grade
12.26
61.44
1.65%
2.28%
31.75
17.00
2.03
2.89
2.02%
4.91%
Turn lane present
Yes
2.31%
13.98
64.63
−1.38%
−3.54%
31.75
17.00
2.03
1.70
0.12%
4.13%
No functioning traffic control
Yes
13.62
68.17
−1.89%
−6.66%
31.75
17.00
2.03
1.39
-0.87%
0.53%
At-fault driver_speeding
Yes
18.66%
61.48
−0.37%
31.75
17.00
2.03
0.00
1.12%
19.79%
At-fault driver_DUI
Yes
25.39%
12.27
61.19
-0.23%
−0.46%
31.75
17.00
2.03
1.97
1.09%
28.45%
Gender
Male
−3.71%
62.61
−1.64%
31.75
17.00
2.03
0.00
0.72%
−2.99%
At-fault driver age
21 years old or younger
−5.68%
31.75
17.00
2.03
0.00
0.00%
−5.68%
22∼31 years old
−4.73%
10.90
64.54
0.53%
−0.72%
31.75
17.00
2.03
2.11
1.07%
−1.55%
32∼41 years old
−5.56%
31.75
17.00
2.03
0.00
0.00%
−5.56%
42∼51 years old
−5.19%
31.75
17.00
2.03
0.00
0.00%
−5.19%
52∼61 years old
−3.62%
31.75
17.00
2.03
0.00
0.00%
−3.62%
62∼71 years old
−3.82%
31.75
17.00
2.03
0.00
0.00%
−3.82%
Point of impact
Front passenger side
−7.47%
13.20
55.94
0.55%
0.33%
31.75
17.00
2.03
2.51
1.25%
−3.71%
Back passenger side
−17.93%
13.20
0.27%
31.75
17.00
2.03
2.38
0.00%
−15.55%
Bumper
16.76%
55.94
4.57%
31.75
17.00
2.03
0.00
2.68%
19.43%
Driver door
9.57%
13.20
55.94
0.25%
0.31%
31.75
17.00
2.03
2.37
1.24%
13.18%
Passenger side behind the driver
−12.64%
31.75
17.00
2.03
0.00
0.00%
−12.64%
Causal vehicle type
Passenger car
−3.06%
55.27
2.81%
31.75
17.00
2.03
0.00
2.07%
−0.99%
Pickup
−4.53%
55.27
0.85%
31.75
17.00
2.03
0.00
1.41%
−3.12%
SUV
55.27
1.26%
31.75
17.00
2.03
0.00
1.55%
1.55%
Noncausal vehicle type
Passenger car
−7.31%
31.75
17.00
2.03
0.00
0.00%
−7.31%
Pickup
−10.40%
31.75
17.00
2.03
0.00
0.00%
−10.40%
SUV
−6.21%
31.75
17.00
2.03
0.00
0.00%
−6.21%
Notes: Y2 is the KABC injury; Y1 is one of “ran stop sign (RSS)” or “failed to yield at stop sign (FYSS)”; is the probability of Y1 when contributing factor X is at the base; is the probability of KABC injury when precrash behavior Y1 is at the base (i.e., “other behaviors”); ;; some cells are empty due to the insignificant estimates ( value >0.1) from the models.
