Item | Testing Data Poisson Regression Model | Testing Data Negative Binomial Model | ||||
Variables | Coeff. Estimate | Wald Chi Square Statistics | P-value | Coeff. Estimate | Wald Chi Square Statistics | P-value |
Intercept | −2.681 | 21.088 | 0.000 | −2.323 | 22.709 | 0.000 |
Rd_char |
|
|
|
|
|
|
1―Straight | −0.109 | 0.343 | 0.046 | −0.193 | 0.371 | 0.044 |
2―U.grade | 0.332 | 7.774 | 0.002 | 0.412 | 6.311 | 0.001 |
3―D.grade | 1.389 | 4.614 | 0.002 | 1.559 | 3.727 | 0.001 |
4―H. Curve | 1.703 | 6.633 | 0.002 | 1.388 | 5.476 | 0.001 |
Rdsurf |
|
|
|
|
|
|
1―Dry | −0.282 | 0.225 | 0.043 | −0.172 | 0.482 | 0.041 |
2―Wet | 1.321 | 5.867 | 0.003 | 1.478 | 5.533 | 0.002 |
3―Muddy | 0.732 | 10.448 | 0.001 | 0.915 | 9.611 | 0.001 |
Weather |
|
|
|
|
|
|
1―Clear | −0.221 | 0.411 | 0.077 | −0.393 | 0.622 | 0.079 |
2―Rain | −1.032 | 4.747 | 0.033 | −1.703 | 7.153 | 0.003 |
3―Snow | 1.744 | 7.182 | 0.002 | 2.433 | 7.911 | 0.001 |
4―Fog | 2.011 | 12.877 | 0.000 | 3.044 | 9.633 | 0.000 |
Light |
|
|
|
|
|
|
1―Day Light | −0.019 | 0.177 | 0.092 | 0.099 | −0.191 | 0.107 |
2―Light ON | −0.153 | 0.242 | 0.041 | 0.331 | −0.338 | 0.044 |
3―No Light | 2.091 | 12.944 | 0.001 | 3.866 | 12.852 | 0.000 |
Drv_age |
|
|
|
|
|
|
1―< 21 yr. | 2.281 | 13.553 | 0.001 | 4.472 | 12.264 | 0.001 |
2―(21 to 65) | −0.141 | 0.093 | 0.032 | −0.394 | 0.435 | 0.003 |
3―> 65 yr. | 2.176 | 13.844 | 0.001 | 5.611 | 12.919 | 0.001 |
Drv_sex |
|
|
|
|
|
|
1―Male | −1.337 | 15.445 | 0.031 | −1.499 | 12.069 | 0.002 |
2―Female | −1.228 | 14.688 | 0.027 | −2.093 | 13.419 | 0.001 |
Vehtype |
|
|
|
|
|
|
1―P. Car | −2.301 | 17.285 | 0.036 | −4.612 | 18.333 | 0.041 |
2―Van | −2.099 | 12.312 | 0.021 | −2.411 | 12.419 | 0.023 |
3―Bus | 1.890 | 10.449 | 0.002 | 2.712 | 9.747 | 0.003 |
4―Truck | 1.909 | 9.781 | 0.002 | 2.644 | 6.552 | 0.002 |
Sec_leng |
|
|
|
|
|
|
1―0.2 km | −1.266 | 2.322 | 0.023 | −2.229 | 5.471 | 0.026 |
2―0.5 km | −1.441 | 5.888 | 0.036 | −2.741 | 6.071 | 0.039 |
3―0.9 km | −1.155 | 2.991 | 0.029 | −1.791 | 5.559 | 0.033 |
AADT | 2.761 | 4.663 | 0.022 | 2.819 | 5.113 | 0.001 |