Table 4: Parameter estimates of ZINB model for total crash frequency.

ParameterDFEstimateStandard errort valueP value

Negative binomial regression part

Intercept10.8500.1615.29<0.0001
Numberofla (2 lane)0
Numberofla (4 lane)1−0.4380.107−4.10<0.0001
RoU (rural)1−0.2700.095−2.840.0045
RoU (urban)0
ADT_100010.0750.00418.20<0.0001
LENGTH10.3950.0705.61<0.0001
FFS1−0.0110.004−2.990.0028

Logistic regression part

Inf_Intercept18.2140.9138.99<0.0001
Inf_ADT1−0.0280.013−2.200.0277
Inf_LENGTH1−71.7138.739−8.21<0.0001
_Alpha11.4350.06522.20<0.0001