|
| Variables | Coefficient | t-stat | Pseudoelasticities (%) |
| Severe injury (SI) | Minor injury (MI) | No injury (NI) |
|
| Constant (SI) | −2.238 | −6.76 | — | — | — |
| Constant (MI) | −1.303 | −2.79 | — | — | — |
| Random parameter (normally distributed) |
| Road without isolation indicator (1 if yes; otherwise, 0) (NI) | 5.974 | 1.78 | 3.84 | 3.84 | −0.73 |
| Standard deviation of the parameter density function | 5.494 | 1.97 | — | — | — |
| Heterogeneity in the mean of random parameter |
| Road without isolation indicator (1 if yes; otherwise, 0) (NI): wet surface indicator (1 if yes; otherwise, 0) | −2.913 | −1.70 | — | — | — |
| Road without isolation indicator (1 if yes; otherwise, 0) (NI): dark-lighted indicator (1 if yes; otherwise, 0) | −5.237 | −1.79 | — | — | — |
| Driver characteristics |
| Expert driving experience indicator (1 if above 15 years; otherwise, 0) (SI) | −0.718 | −2.09 | −11.72 | 1.37 | 0.70 |
| Driver under alcohol influence indicator (1 if yes; otherwise, 0) (MI) | 2.057 | 9.10 | −19.69 | 16.88 | −14.37 |
| Vehicle characteristics |
| Truck indicator (1 if yes; otherwise, 0) (SI) | 1.119 | 4.09 | 12.35 | −4.98 | −3.03 |
| Truck indicator (1 if yes; otherwise, 0) (MI) | −2.335 | −4.86 | 1.73 | −34.45 | 1.01 |
| Improper braking and steering indicator (1 if yes; otherwise, 0) (SI) | −1.722 | −6.83 | −65.71 | 7.12 | 3.34 |
| Improper lane changing indicator (1 if yes; otherwise, 0) (SI) | −1.468 | −3.75 | −17.21 | 1.93 | 1.10 |
| Roadway characteristics |
| Wet surface indicator (1 if yes; otherwise, 0) (SI) | −0.709 | −2.23 | −13.71 | 1.60 | 0.89 |
| Intersection indicator (1 if yes; otherwise, 0) (MI) | −0.622 | −2.09 | 2.00 | −8.88 | 1.11 |
| Small downhill grade indicator (1 if −2–0% vertical grade; otherwise, 0) (SI) | −2.548 | −2.20 | −15.69 | 0.57 | 0.16 |
| Small uphill grade indicator (1 if 0–2% vertical grade; otherwise, 0) (MI) | −1.424 | −8.49 | 26.80 | −100.63 | 18.01 |
| Crash characteristics |
| Head-on collision indicator (1 if yes; otherwise, 0) (NI) | 1.136 | 1.88 | −2.42 | −2.42 | 0.54 |
| Autumn indicator (1 if yes; otherwise, 0) (SI) | −0.501 | −1.81 | −11.56 | 1.63 | 0.92 |
| Winter indicator (1 if yes; otherwise, 0) (MI) | 0.766 | 2.92 | −3.48 | 6.22 | −2.83 |
| Summer indicator (1 if yes; otherwise, 0) (NI) | 0.435 | 2.22 | −10.69 | −10.69 | 2.40 |
| Sunny indicator (1 if yes; otherwise, 0) (MI) | −0.891 | −2.20 | 1.75 | −20.91 | 0.85 |
| Sunny indicator (1 if yes; otherwise, 0) (NI) | 0.444 | 1.69 | −8.46 | −8.46 | 1.47 |
| Dark lighted indicator (1 if yes; otherwise, 0) (SI) | −1.282 | −4.71 | −57.56 | 5.20 | 3.32 |
| Temporal characteristics |
| Nighttime off-peak indicator (1 if time 19:30–23:59; otherwise, 0) (SI) | −1.285 | −3.07 | −14.25 | 2.03 | 0.87 |
| Nighttime off-peak indicator (1 if time 19:30–23:59; otherwise, 0) (MI) | −1.522 | −2.81 | 1.60 | −17.69 | 0.54 |
| Early morning indicator (1 if time 00:00–7:00; otherwise, 0) (MI) | −1.759 | −2.87 | 1.04 | −19.64 | 0.48 |
|
| Number of observations above and below zero generated from the random parameter | Above zero | Below zero |
|
| Road without isolation indicator (1 if yes; otherwise, 0) (NI) | 82.59% | 17.41% |
| Goodness-of-fit measures | | |
| McFadden R-squared | 0.478 | |
|
