biogeme 2.6a [Mon Apr 17 15:32:48 CEST 2017]

Michel Bierlaire, EPFL

This file has automatically been generated.

Tue Apr 18 19:33:02 2017

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

Example of a mixture of logit model with panel data, for a transportation mode choice with 3 alternatives:
- Train
- Car
- Swissmetro, an hypothetical high-speed train
We introduce error components with alternative specific variance. The model is not identified, but its estimation is required to identify which SIGMA should be normalized (see Walker, 2001).
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 assoviated with each mass point are W_0 and W_OTHER, respectively.
Model: Mixed Logit for panel data
Number of Hess-Train draws: 500
Number of estimated parameters: 9
Number of observations: 6768
Number of individuals: 752
Null log likelihood: -6964.663
Init log likelihood: -6171.531
Final log likelihood: -3715.863
Likelihood ratio test: 6497.599
Rho-square: 0.466
Adjusted rho-square: 0.465
Final gradient norm: +2.010e+11
Diagnostic: Normal termination. Obj: 6.05545e-06 Const: 6.05545e-06
Iterations: 53
Run time: 18:22
Variance-covariance: from finite difference hessian
Sample file: ../swissmetro.dat

Utility parameters

Name Value Std err t-testp-value
ASC_CAR0.1570.014310.930.00
ASC_SM0.00fixed
ASC_TRAIN-1.310.214-6.120.00
B_COST-2.780.143-19.420.00
B_TIME_00.00fixed
B_TIME_OTHER-4.420.159-27.730.00
SIGMA_CAR3.330.21115.750.00
SIGMA_SM1.420.1827.830.00
SIGMA_TRAIN-3.430.230-14.950.00
W_09.95e-122.72e-100.040.97*
W_OTHER1.000.048620.570.00
ZERO0.00fixed

Utility functions

IdNameAvailabilitySpecification
1A1_TRAINTRAIN_AV_SPASC_TRAIN * one + B_TIME * TRAIN_TT_SCALED + B_COST * TRAIN_COST_SCALED + ZERO [ SIGMA_TRAIN ] * one
2A2_SMSM_AVASC_SM * one + B_TIME * SM_TT_SCALED + B_COST * SM_COST_SCALED + ZERO [ SIGMA_SM ] * one
3A3_CarCAR_AV_SPASC_CAR * one + B_TIME * CAR_TT_SCALED + B_COST * CAR_CO_SCALED + ZERO [ SIGMA_CAR ] * one

Variance of random coefficients

NameValueStd errt-testRobust Std errRobust t-test
ZERO_SIGMA_CAR11.11.417.87
ZERO_SIGMA_SM2.020.5163.92
ZERO_SIGMA_TRAIN1.64e+1771.581041049566046618132718899763830902769673906427582254461119785963330686852859266869775041594777911198389303320394027517804685217257791990721444195332318679275862932195563244879872.00

Correlation of coefficients

Coefficient1 Coefficient2CovarianceCorrelationt-testp-valueRob. cov.Rob. corr.Rob. t-testp-value
ASC_CAR ASC_TRAIN-2.92e-05-0.009526.830.00
ASC_CAR B_COST-5.47e-05-0.026620.360.00
ASC_CAR B_TIME_OTHER9.05e-050.039628.700.00
ASC_CAR SIGMA_CAR7.34e-050.0242-15.000.00
ASC_CAR SIGMA_SM-1.51e-05-0.00579-6.950.00
ASC_CAR SIGMA_TRAIN2.93e-050.0089015.610.00
ASC_CAR W_00.002165.54e+080.001.00 *
ASC_CAR W_OTHER7.07e-141.01e-10-16.640.00
ASC_TRAIN B_COST0.01130.3667.020.00
ASC_TRAIN B_TIME_OTHER-0.0103-0.30210.240.00
ASC_TRAIN SIGMA_CAR0.01680.372-19.450.00
ASC_TRAIN SIGMA_SM0.0002420.00622-9.770.00
ASC_TRAIN SIGMA_TRAIN0.02230.4549.130.00
ASC_TRAIN W_02.98e-175.11e-07-6.120.00
ASC_TRAIN W_OTHER-0.00120-0.116-10.270.00
B_COST B_TIME_OTHER0.007710.3389.350.00
B_COST SIGMA_CAR-0.0135-0.446-20.120.00
B_COST SIGMA_SM-0.00855-0.329-15.830.00
B_COST SIGMA_TRAIN0.02530.7674.310.00
B_COST W_01.01e-172.60e-07-19.420.00
B_COST W_OTHER0.004740.680-32.640.00
B_TIME_OTHER SIGMA_CAR-0.0275-0.816-21.910.00
B_TIME_OTHER SIGMA_SM-0.00134-0.0463-23.640.00
B_TIME_OTHER SIGMA_TRAIN0.02990.818-7.280.00
B_TIME_OTHER W_01.48e-173.40e-07-27.730.00
B_TIME_OTHER W_OTHER0.0008100.105-33.520.00
SIGMA_CAR SIGMA_SM-0.000998-0.02606.760.00
SIGMA_CAR SIGMA_TRAIN-0.0398-0.81916.080.00
SIGMA_CAR W_0-2.49e-17-4.33e-0715.750.00
SIGMA_CAR W_OTHER0.002580.25111.380.00
SIGMA_SM SIGMA_TRAIN-0.00384-0.092115.890.00
SIGMA_SM W_0-3.37e-20-6.81e-107.830.00
SIGMA_SM W_OTHER0.001620.1832.360.02
SIGMA_TRAIN W_03.30e-175.28e-07-14.950.00
SIGMA_TRAIN W_OTHER-9.94e-05-0.00890-18.850.00
W_0 W_OTHER-1.15e-18-8.68e-08-20.570.00

User defined linear constraints

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

Smallest singular value of the hessian: 4.4737e-06

Unidentifiable model

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

Sing. value=4.4737e-06
0.00168287*Param[26]
-0.0752131*Param[34]
0.705103*Param[44]
-0.705103*Param[45]
Sing. value=5.27237e-06
0.00397538*ASC_TRAIN
0.00118951*B_COST
0.00248431*B_TIME_OTHER
-0.00229561*SIGMA_CAR
-0.000711553*SIGMA_SM
0.00418114*SIGMA_TRAIN
-0.0381252*Param[9]
0.031762*Param[10]
-0.00585088*Param[11]
-0.000699227*Param[12]
-0.00222232*Param[13]
0.00863205*Param[14]
-0.0053476*Param[15]
-0.000170112*Param[17]
0.0356615*Param[18]
0.0784948*Param[19]
0.000286429*Param[20]
-0.00130339*Param[21]
-0.00168432*Param[22]
-0.234094*Param[23]
-0.00323306*Param[24]
0.951375*Param[26]
-0.00395284*Param[27]
-0.0292212*Param[28]
0.00164591*Param[29]
0.000437576*Param[30]
-0.00147906*Param[31]
0.0553174*Param[32]
0.00255462*Param[33]
-0.000120044*Param[34]
-0.0365951*Param[36]
-0.0669605*Param[37]
-0.0004223*Param[38]
-0.00032695*Param[39]
0.000875599*Param[40]
0.142185*Param[41]
-0.00115635*Param[42]
-0.00114208*Param[44]
0.00114137*Param[45]
Sing. value=6.29111e-06
-0.000253471*Param[26]
-0.997167*Param[34]
-0.0531836*Param[44]
0.0531833*Param[45]
Sing. value=6.30888e-06
1*Param[16]