Analysis of Factors Affecting the Severity of Injuries in Electric Two-Wheeled Vehicle Crashes with or without Violation: A Random Parametric Logit Model considering Heterogeneity of Means and Variances
Table 5
Estimating the severity of injuries in electric two wheeled vehicle accidents using a random parameter logit model considering the heterogeneity of mean and variance.
Variable
No violation
Existence of violation
MI
SF
MI
SF
Mean
S.D
Mean
S.D
Mean
S.D
Mean
S.D
Rider factor
Male
—
—
—
—
−1.188
0.240
−0.958
0.873
18–32
−0.236
0.154
—
—
—
—
—
—
46–60
—
—
—
—
—
—
0.796
0.655
>60
0.151
0.178
0.347
0.212
0.786
0.975
2.017
1.316
Road factor
Pavement damage
−2.241
0.231
—
—
—
—
0.148
0.247
Dusk/dawn
—
—
—
—
−0.493
0.347
—
—
Street lights at night
−1.145
0.175
—
—
0.258
0.455
—
—
No street lamp at night
0.767
0.159
0.838
0.233
0.426
0.725
—
—
Nonmotorized lane
—
—
—
—
−0.288
0.105
−0.554
0.143
Mixed lane
1.323
0.135
1.171
0.197
0.723
0.535
0.571
0.397
Sidewalk
—
—
−0.552
0.155
—
—
—
—
Collision factor
Other angles
—
—
−1.156
0.237
−1.668
0.537
−1.325
0.736
Environmental factor
Uncontrolled
−0.236
0.135
−0.456
0.142
0.320
0.294
—
—
Marking control
—
—
—
—
0.532
0.322
—
—
Autumn
0.367
0.155
—
—
—
—
—
—
Severe weather
1.149
0.211
—
—
0.804
1.103
—
—
<200 m
—
—
0.485
0.181
—
—
0.249
0.645
Random parameter
Severe weather
0.804
0.212
—
—
1.149
1.853
—
—
<200 m
—
—
0.260
0.738
—
—
0.486
1.163
Heterogeneity in the means of random parameters
Severe weather: No street lamp at nigh
—
—
—
—
0.301
0.217
—
—
Severe weather: >60
0.433
0.212
—
—
—
—
—
—
Severe weather: Uncontrolled
—
—
—
—
−0.532
1.123
—
—
<200 m: Mixed lane
—
—
−0.322
0.671
—
—
0.525
0.278
Heterogeneity in the variances of random parameters