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

Parameter DF Estimate Standard error t value P value Negative binomial regression part Intercept 1 0.850 0.161 5.29 <0.0001 Numberofla (2 lane) 0 — — — — Numberofla (4 lane) 1 −0.438 0.107 −4.10 <0.0001 RoU (rural) 1 −0.270 0.095 −2.84 0.0045 RoU (urban) 0 — — — — ADT_1000 1 0.075 0.004 18.20 <0.0001 LENGTH 1 0.395 0.070 5.61 <0.0001 FFS 1 −0.011 0.004 −2.99 0.0028 Logistic regression part Inf_Intercept 1 8.214 0.913 8.99 <0.0001 Inf_ADT 1 −0.028 0.013 −2.20 0.0277 Inf_LENGTH 1 −71.713 8.739 −8.21 <0.0001 _Alpha 1 1.435 0.065 22.20 <0.0001