.. DO NOT EDIT. .. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY. .. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE: .. "auto_examples/swissmetro/plot_b17lognormal_mixture_integral.py" .. LINE NUMBERS ARE GIVEN BELOW. .. only:: html .. note:: :class: sphx-glr-download-link-note :ref:`Go to the end ` to download the full example code .. rst-class:: sphx-glr-example-title .. _sphx_glr_auto_examples_swissmetro_plot_b17lognormal_mixture_integral.py: Mixture with lognormal distribution =================================== Example of a mixture of logit models. The mixing distribution is distributed as a log normal. Compared to :ref:`plot_b17lognormal_mixture`, the integration is performed using numerical integration instead of Monte-Carlo approximation. :author: Michel Bierlaire, EPFL :date: Mon Apr 10 12:13:23 2023 .. GENERATED FROM PYTHON SOURCE LINES 15-28 .. code-block:: default import biogeme.biogeme_logging as blog import biogeme.biogeme as bio import biogeme.distributions as dist from biogeme import models from biogeme.expressions import ( Beta, RandomVariable, exp, log, Integrate, ) .. GENERATED FROM PYTHON SOURCE LINES 29-30 See the data processing script: :ref:`swissmetro_data`. .. GENERATED FROM PYTHON SOURCE LINES 30-47 .. code-block:: default from swissmetro_data import ( database, CHOICE, SM_AV, CAR_AV_SP, TRAIN_AV_SP, TRAIN_TT_SCALED, TRAIN_COST_SCALED, SM_TT_SCALED, SM_COST_SCALED, CAR_TT_SCALED, CAR_CO_SCALED, ) logger = blog.get_screen_logger(level=blog.INFO) logger.info('Example b17lognormal_mixture_integral.py') .. rst-class:: sphx-glr-script-out .. code-block:: none Example b17lognormal_mixture_integral.py .. GENERATED FROM PYTHON SOURCE LINES 48-49 Parameters to be estimated. .. GENERATED FROM PYTHON SOURCE LINES 49-54 .. code-block:: default ASC_CAR = Beta('ASC_CAR', 0, None, None, 0) ASC_TRAIN = Beta('ASC_TRAIN', 0, None, None, 0) ASC_SM = Beta('ASC_SM', 0, None, None, 1) B_COST = Beta('B_COST', 0, None, None, 0) .. GENERATED FROM PYTHON SOURCE LINES 55-57 Define a random parameter, normally distributed, designed to be used. for Monte-Carlo simulation .. GENERATED FROM PYTHON SOURCE LINES 57-59 .. code-block:: default B_TIME = Beta('B_TIME', 0, None, None, 0) .. GENERATED FROM PYTHON SOURCE LINES 60-61 It is advised not to use 0 as starting value for the following parameter.. .. GENERATED FROM PYTHON SOURCE LINES 61-63 .. code-block:: default B_TIME_S = Beta('B_TIME_S', 1, -2, 2, 0) .. GENERATED FROM PYTHON SOURCE LINES 64-66 Define a random parameter, log normally distributed, designed to be used for numerical integration. .. GENERATED FROM PYTHON SOURCE LINES 66-70 .. code-block:: default omega = RandomVariable('omega') B_TIME_RND = -exp(B_TIME + B_TIME_S * omega) density = dist.normalpdf(omega) .. GENERATED FROM PYTHON SOURCE LINES 71-72 Definition of the utility functions. .. GENERATED FROM PYTHON SOURCE LINES 72-76 .. code-block:: default V1 = ASC_TRAIN + B_TIME_RND * TRAIN_TT_SCALED + B_COST * TRAIN_COST_SCALED V2 = ASC_SM + B_TIME_RND * SM_TT_SCALED + B_COST * SM_COST_SCALED V3 = ASC_CAR + B_TIME_RND * CAR_TT_SCALED + B_COST * CAR_CO_SCALED .. GENERATED FROM PYTHON SOURCE LINES 77-78 Associate utility functions with the numbering of alternatives. .. GENERATED FROM PYTHON SOURCE LINES 78-80 .. code-block:: default V = {1: V1, 2: V2, 3: V3} .. GENERATED FROM PYTHON SOURCE LINES 81-82 Associate the availability conditions with the alternatives. .. GENERATED FROM PYTHON SOURCE LINES 82-84 .. code-block:: default av = {1: TRAIN_AV_SP, 2: SM_AV, 3: CAR_AV_SP} .. GENERATED FROM PYTHON SOURCE LINES 85-86 Conditional to omega, we have a logit model (called the kernel). .. GENERATED FROM PYTHON SOURCE LINES 86-88 .. code-block:: default condprob = models.logit(V, av, CHOICE) .. GENERATED FROM PYTHON SOURCE LINES 89-90 We integrate over omega using numerical integration. .. GENERATED FROM PYTHON SOURCE LINES 90-92 .. code-block:: default logprob = log(Integrate(condprob * density, 'omega')) .. GENERATED FROM PYTHON SOURCE LINES 93-94 Create the Biogeme object. .. GENERATED FROM PYTHON SOURCE LINES 94-97 .. code-block:: default the_biogeme = bio.BIOGEME(database, logprob) the_biogeme.modelName = 'b17lognormal_mixture_integral' .. rst-class:: sphx-glr-script-out .. code-block:: none File biogeme.toml has been parsed. .. GENERATED FROM PYTHON SOURCE LINES 98-99 Estimate the parameters .. GENERATED FROM PYTHON SOURCE LINES 99-101 .. code-block:: default results = the_biogeme.estimate() .. rst-class:: sphx-glr-script-out .. code-block:: none *** Initial values of the parameters are obtained from the file __b17lognormal_mixture_integral.iter Cannot read file __b17lognormal_mixture_integral.iter. Statement is ignored. Optimization algorithm: hybrid Newton/BFGS with simple bounds [simple_bounds] ** Optimization: Newton with trust region for simple bounds Iter. ASC_CAR ASC_TRAIN B_COST B_TIME B_TIME_S Function Relgrad Radius Rho 0 0.18 -0.4 -1 0.36 1 5.3e+03 0.018 10 1 ++ 1 0.18 -0.34 -1.3 0.57 1.1 5.2e+03 0.0026 1e+02 1.1 ++ 2 0.17 -0.34 -1.4 0.58 1.2 5.2e+03 0.00017 1e+03 1 ++ 3 0.17 -0.34 -1.4 0.58 1.2 5.2e+03 2.9e-06 1e+03 1 ++ Results saved in file b17lognormal_mixture_integral.html Results saved in file b17lognormal_mixture_integral.pickle .. GENERATED FROM PYTHON SOURCE LINES 102-104 .. code-block:: default print(results.short_summary()) .. rst-class:: sphx-glr-script-out .. code-block:: none Results for model b17lognormal_mixture_integral Nbr of parameters: 5 Sample size: 6768 Excluded data: 3960 Final log likelihood: -5231.419 Akaike Information Criterion: 10472.84 Bayesian Information Criterion: 10506.94 .. GENERATED FROM PYTHON SOURCE LINES 105-107 .. code-block:: default pandas_results = results.getEstimatedParameters() pandas_results .. raw:: html
Value Rob. Std err Rob. t-test Rob. p-value
ASC_CAR 0.174559 0.062655 2.786034 5.335733e-03
ASC_TRAIN -0.345857 0.073252 -4.721472 2.341435e-06
B_COST -1.380475 0.097826 -14.111584 0.000000e+00
B_TIME 0.575771 0.071228 8.083497 6.661338e-16
B_TIME_S 1.239158 0.132469 9.354327 0.000000e+00


.. rst-class:: sphx-glr-timing **Total running time of the script:** (0 minutes 8.113 seconds) .. _sphx_glr_download_auto_examples_swissmetro_plot_b17lognormal_mixture_integral.py: .. only:: html .. container:: sphx-glr-footer sphx-glr-footer-example .. container:: sphx-glr-download sphx-glr-download-python :download:`Download Python source code: plot_b17lognormal_mixture_integral.py ` .. container:: sphx-glr-download sphx-glr-download-jupyter :download:`Download Jupyter notebook: plot_b17lognormal_mixture_integral.ipynb ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_