Research Article
Distinguishing between Rural and Urban Road Segment Traffic Safety Based on Zero-Inflated Negative Binomial Regression Models
Table 5
Parameter estimates of ZINB model for injury and fatal crash frequency.
| | Parameter | DF | Estimate | Standard error | t value | P value |
| | Negative binomial regression part |
| | Intercept | 1 | −1.272 | 0.093 | −13.73 | <0.0001 | | Numberofla (2 lane) | 0 | — | — | — | — | | Numberofla (4 lane) | 1 | −0.398 | 0.098 | −4.08 | <0.0001 | | RoU (rural) | 1 | −0.232 | 0.118 | −1.96 | 0.0496 | | RoU (urban) | 0 | — | — | — | — | | ADT_1000 | 1 | 0.060 | 0.004 | 15.58 | <0.0001 | | LENGTH | 1 | 0.338 | 0.068 | 5.00 | <0.0001 |
| | Logistic regression part |
| | Inf_Intercept | 1 | 5.404 | 0.850 | 6.35 | <0.0001 | | Numberofla (2 lane) | 0 | — | — | — | — | | Numberofla (4 lane) | 1 | −0.967 | 0.352 | −2.75 | 0.0060 | | Inf_ADT_1000 | 1 |
0.035
| 0.016 |
2.21
| 0.0268 | | Inf_LENGTH | 1 | −38.325 | 6.436 | −5.95 | <0.0001 | | _Alpha | 1 |
1.073
| 0.124 | 8.64 | <0.0001 |
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