.. DO NOT EDIT. .. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY. .. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE: .. "auto_examples/bayesian_swissmetro/plot_b18b_ordinal_probit.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_bayesian_swissmetro_plot_b18b_ordinal_probit.py: 18. Ordinal probit model ======================== Bayesian estimation of an ordinal probit model. This is just to illustrate the syntax, as the data are not ordered. But the example assume, for the sake of it, that the alternatives are ordered as 1->2->3 Michel Bierlaire, EPFL Mon Nov 17 2025, 16:44:27 .. GENERATED FROM PYTHON SOURCE LINES 13-20 .. code-block:: Python from IPython.core.display_functions import display import biogeme.biogeme_logging as blog from biogeme.bayesian_estimation import BayesianResults, get_pandas_estimated_parameters from biogeme.biogeme import BIOGEME from biogeme.expressions import Beta, OrderedLogProbit .. GENERATED FROM PYTHON SOURCE LINES 21-22 See the data processing script: :ref:`swissmetro_data`. .. GENERATED FROM PYTHON SOURCE LINES 22-24 .. code-block:: Python from swissmetro_data import CHOICE, TRAIN_COST_SCALED, TRAIN_TT_SCALED, database .. GENERATED FROM PYTHON SOURCE LINES 25-26 We define a small but positive lower bound .. GENERATED FROM PYTHON SOURCE LINES 26-31 .. code-block:: Python POSITIVE_LOWER_BOUND = 1.0e-5 logger = blog.get_screen_logger(level=blog.INFO) logger.info('Example b18b_ordinal_probit.py') .. rst-class:: sphx-glr-script-out .. code-block:: none Example b18b_ordinal_probit.py .. GENERATED FROM PYTHON SOURCE LINES 32-33 Parameters to be estimated .. GENERATED FROM PYTHON SOURCE LINES 33-36 .. code-block:: Python b_time = Beta('b_time', 0, None, None, 0) b_cost = Beta('b_cost', 0, None, None, 0) .. GENERATED FROM PYTHON SOURCE LINES 37-38 Threshold parameters for the ordered probit. .. GENERATED FROM PYTHON SOURCE LINES 40-41 :math:`\tau_1 \leq 0`. .. GENERATED FROM PYTHON SOURCE LINES 41-43 .. code-block:: Python tau1 = Beta('tau1', -1, None, 0, 0) .. GENERATED FROM PYTHON SOURCE LINES 44-45 :math:`\delta_2 \geq 0`. .. GENERATED FROM PYTHON SOURCE LINES 45-47 .. code-block:: Python delta2 = Beta('delta2', 2, POSITIVE_LOWER_BOUND, None, 0) .. GENERATED FROM PYTHON SOURCE LINES 48-49 :math:`\tau_2 = \tau_1 + \delta_2` .. GENERATED FROM PYTHON SOURCE LINES 49-51 .. code-block:: Python tau2 = tau1 + delta2 .. GENERATED FROM PYTHON SOURCE LINES 52-53 Utility .. GENERATED FROM PYTHON SOURCE LINES 53-55 .. code-block:: Python utility = b_time * TRAIN_TT_SCALED + b_cost * TRAIN_COST_SCALED .. GENERATED FROM PYTHON SOURCE LINES 56-57 Associate each discrete indicator with an interval. .. GENERATED FROM PYTHON SOURCE LINES 57-65 .. code-block:: Python log_probability = OrderedLogProbit( eta=utility, cutpoints=[tau1, tau2], y=CHOICE, categories=[1, 2, 3], neutral_labels=[], ) .. GENERATED FROM PYTHON SOURCE LINES 66-67 Create the Biogeme object. .. GENERATED FROM PYTHON SOURCE LINES 67-70 .. code-block:: Python the_biogeme = BIOGEME(database, log_probability) the_biogeme.model_name = 'b18b_ordinal_probit' .. rst-class:: sphx-glr-script-out .. code-block:: none Biogeme parameters read from biogeme.toml. .. GENERATED FROM PYTHON SOURCE LINES 71-72 Estimate the parameters. .. GENERATED FROM PYTHON SOURCE LINES 72-79 .. code-block:: Python try: results = BayesianResults.from_netcdf( filename=f'saved_results/{the_biogeme.model_name}.nc' ) except FileNotFoundError: results = the_biogeme.bayesian_estimation() .. rst-class:: sphx-glr-script-out .. code-block:: none *** Initial values of the parameters are obtained from the file __b18b_ordinal_probit.iter Cannot read file __b18b_ordinal_probit.iter. Statement is ignored. Starting values for the algorithm: {} /Users/bierlair/MyFiles/github/biogeme/src/biogeme/biogeme.py:832: UserWarning: Note: JAX currently sees 1 CPU device. To parallelize across CPU devices, set XLA_FLAGS as above and restart Python/Jupyter. macOS / Linux (bash/zsh): export XLA_FLAGS="--xla_force_host_platform_device_count=" Jupyter (new cell, before `import jax`): %env XLA_FLAGS="--xla_force_host_platform_device_count=" warning_cpu_devices() Detected CPU devices: 1 | System logical cores: 12 Current XLA_FLAGS: (none set) Platform: Darwin 24.6.0 | Python: 3.13.1 Auto sampling: JAX available (devices=1, platforms=cpu) → numpyro/vectorized /Users/bierlair/MyFiles/github/biogeme/src/biogeme/biogeme.py:859: UserWarning: The effect of Potentials on other parameters is ignored during prior predictive sampling. This is likely to lead to invalid or biased predictive samples. pm.sample_prior_predictive( 0%| | 0/4000 [00:00` .. container:: sphx-glr-download sphx-glr-download-python :download:`Download Python source code: plot_b18b_ordinal_probit.py ` .. container:: sphx-glr-download sphx-glr-download-zip :download:`Download zipped: plot_b18b_ordinal_probit.zip ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_