Comparison of Factors Affecting Crash Severities in Hit-and-Run and Non-Hit-and-Run Crashes
Table 3
HR multinomial logistic regression model results.
Variables
Injury crashes vs. PDO crashes
Fatal crashes vs. PDO crashes
Estimate
P value
Odds ratio (95% CI)
Estimate
P value
Odds ratio (95% CI)
Intercept
-4.026
0.000
-10.864
0.000
Lighting condition (relative to daylight)
Dawn
0.420
0.048
1.522(1.003, 2.308)
-
-
-
Dusk
-
-
-
2.407
0.035
11.102(0.822, 149.864)
Darkness
-
-
-
-
-
-
Darkness, lighted road
0.320
0.000
1.377(1.193, 1.590)
1.528
0.005
4.609(0.910, 23.337)
Road surface condition (relative to dry)
Wet
-0.265
0.004
0.767(0.641, 0.917)
-
-
-
Snow or slush
-0.547
0.005
0.579(0.395, 0.849)
-
-
-
Number of units involved (relative to one unit)
2 units
-
-
-
-
-
-
More than 2 units
1.891
0.000
6.626(2.521, 17.414)
-
-
-
Crash type (relative to fixed object crash)
Head on
-
-
-
-
-
-
Sideswipe opposite direction
-
-
-
-
-
-
Pedal cyclist
3.279
0.000
26.562(10.973, 64.297)
-
-
-
Pedestrian
3.867
0.000
47.808(20.042, 114.045)
-
-
-
Angle
-
-
-
-
-
-
Turning
-
-
-
-
-
-
Sideswipe same direction
-1.118
0.011
0.327(0.138, 0.776)
-
-
-
Parked motor vehicle
-2.884
0.000
0.056(0.023, 0.135)
-
-
-
Rear end
-
-
-
-
-
-
Trafficway type (relative to non-divided road)
Divided with median barrier
0.188
0.008
1.206(1.051, 1.385)
1.603
0.025
4.970(1.224, 20.179)
One-way
-0.233
0.032
0.792(0.640, 0.980)
-
-
-
Parking lot
-0.626
0.002
0.535(0.359, 0.796)
-
-
-
Crash damage in dollar value (relative to $500 or less)
$501 - $1500
-
-
-
-
-
-
Over $1500
1.073
0.000
2.925(2.353, 3.636)
3.368
0.002
29.024(3.466, 243.017)
Crash hour (relative to non-peak hour)
AM peak hour
-
-
-
-
-
-
PM peak hour
-0.250
0.004
0.779(0.657, 0.923)
-
-
-
-2Log-likelihood for the model with only the intercept: 7889.860 -2Log-likelihood for the final model: 3694.060 Goodness of fit test: deviance = 2655.644, P = 1.000 Pseudo-R2: Cox & Snell = 0.165; Nagelkerke = 0.417; McFadden = 0.358 Overall prediction accuracy: 94.8%
