Table 4a Ordered Probit Model for Trip Occupancy: All Trip Purposes
Table 4a
Ordered Probit Model for Trip Occupancy: All Trip Purposes
| Dependent variable: trip occupancy (all purposes) | Beta | SE | t-stat | P-value |
|---|---|---|---|---|
| Constant | 0.565 | 0.007 | 79.90 | 0.000 |
| HH members per vehicle owned | 0.340 | 0.002 | 153.00 | 0.000 |
| Income per household member | 1.06E-05 | 2.05E-07 | 51.50 | 0.000 |
| Population density | 8.79E-06 | 4.27E-07 | 20.60 | 0.000 |
| Weekend day indicator | 0.474 | 0.005 | 91.20 | 0.000 |
| SUV indicator | 0.174 | 0.008 | 20.90 | 0.000 |
| Pickup indicator | 0.229 | 0.008 | 30.40 | 0.000 |
| Minivan indicator | 0.500 | 0.006 | 78.80 | 0.000 |
| Shopping indicator | 0.021 | 0.006 | 3.21 | 0.001 |
| Eat out indicator | 0.544 | 0.011 | 49.20 | 0.000 |
| μo | 0.000 | na | na | na |
| μ1 | 0.875 | 0.003 | 302.00 | 0.000 |
| μ2 | 1.431 | 0.004 | 365.00 | 0.000 |
| μ3 | 2.039 | 0.006 | 368.00 | 0.000 |
Note: Trip occupancy is grouped into 1, 2, 3, 4, and 5+ person levels.
| Log-likelihood function | |
|---|---|
| Constant only | 324471.0 |
| Convergence | 298694.3 |
| Pseudo-R2 | 0.079 |
Number of observations: 263,031 trips
Model form: Pr(Occupancy = 1) = Pr(μ* ≤ μo), Pr(Occupancy = 2) = Pr(μo ≤ μ* ≤ m1), Pr(Occupancy = 3) = Pr(μ1 ≤ μ* ≤ μ2), Pr(Occupancy = 4) = Pr(μ2 ≤ μ* ≤ μ3), and Pr(Occupancy ≥ 5) = Pr(μ3 ≤ μ*), where μ* = β′X + ε, and ε ~ Normal(0, 1)