biogeme 2.5 [Dim 19 jui 2016 17:58:58 CEST]

Michel Bierlaire, EPFL

This file has automatically been generated.

Wed Jul 6 20:06:09 2016

Tip: click on the columns headers to sort a table [Credits]

Example of a logit model for a transportation mode choice with 3 alternatives:
- Train
- Car
- Swissmetro, an hypothetical high-speed train
The time coefficient is assumed to be distributed. It is a discrete distribution with two mass points, one at 0, and one at B_TIME_OTHER. The probabilities associated with each mass point are W_0 and W_OTHER, respectively.
Note that the model is unidentifiable. The objective of this example is to illustrate the Biogeme syntax only.
Model: Logit
Number of estimated parameters: 6
Number of observations: 6768
Number of individuals: 6768
Null log likelihood: -6964.663
Init log likelihood: -6964.663
Final log likelihood: -5208.498
Likelihood ratio test: 3512.330
Rho-square: 0.252
Adjusted rho-square: 0.251
Final gradient norm: +9.571e+03
Diagnostic: Normal termination. Obj: 6.05545e-06 Const: 6.05545e-06
Iterations: 20
Run time: 00:00
Variance-covariance: from analytical hessian
Sample file: ../swissmetro.dat

Utility parameters

Name Value Std err t-testp-value
ASC_CAR0.1250.02524.950.00
ASC_SM0.00fixed
ASC_TRAIN-0.3980.0259-15.380.00
B_COST-1.260.0387-32.650.00
B_TIME_00.00fixed
B_TIME_OTHER-2.801.21e+07-0.001.00*
W_00.2511.80e+3080.001.00*
W_OTHER0.7491.80e+3080.001.00*

Utility functions

IdNameAvailabilitySpecification
1A1_TRAINTRAIN_AV_SPASC_TRAIN * one + B_TIME * TRAIN_TT_SCALED + B_COST * TRAIN_COST_SCALED
2A2_SMSM_AVASC_SM * one + B_TIME * SM_TT_SCALED + B_COST * SM_COST_SCALED
3A3_CarCAR_AV_SPASC_CAR * one + B_TIME * CAR_TT_SCALED + B_COST * CAR_CO_SCALED

Correlation of coefficients

Coefficient1 Coefficient2CovarianceCorrelationt-testp-valueRob. cov.Rob. corr.Rob. t-testp-value
ASC_CAR ASC_TRAIN0.0002570.39518.610.00
ASC_CAR B_COST0.0003280.33736.150.00
ASC_CAR B_TIME_OTHER1.22e-134.00e-190.001.00 *
ASC_CAR W_03.07e-140.000.001.00 *
ASC_CAR W_OTHER-3.06e-140.000.001.00 *
ASC_TRAIN B_COST0.0002190.21920.840.00
ASC_TRAIN B_TIME_OTHER0.0001695.40e-100.001.00 *
ASC_TRAIN W_0-0.0001520.000.001.00 *
ASC_TRAIN W_OTHER0.0001520.000.001.00 *
B_COST B_TIME_OTHER0.001783.80e-090.001.00 *
B_COST W_0-0.001600.000.001.00 *
B_COST W_OTHER0.001600.000.001.00 *
B_TIME_OTHER W_0-1.31e+140.000.001.00 *
B_TIME_OTHER W_OTHER1.31e+140.000.001.00 *
W_0 W_OTHER4.71e+151.000.001.00 *

User defined linear constraints

1*W_0 + 1*W_OTHER = 1 [1 = 1]

Smallest singular value of the hessian: 4.02191e-17

Unidentifiable model

The log likelihood is (almost) flat along the following combinations of parameters

Sing. value=4.02191e-17
0.0128966*B_TIME_OTHER
0.463148*W_0
-0.463148*W_OTHER
0.00240279*Param[9]
0.462416*Param[10]
-0.26754*Param[11]
-0.0018025*Param[15]
-0.26754*Param[16]
0.462416*Param[17]
Sing. value=1.08825e-06
-0.973847*B_TIME_OTHER
0.00613343*W_0
-0.00613343*W_OTHER
-0.18144*Param[9]
0.00612374*Param[10]
-0.00354301*Param[11]
0.13611*Param[15]
-0.00354301*Param[16]
0.00612374*Param[17]