Latent Class SimpleMNL and ConditionalMNL

Latent Class MNL models.

`LatentClassConditionalLogit`

Bases: BaseLatentClassModel

Latent Class for ConditionalLogit.

Source code in choice_learn/models/latent_class_mnl.py

class LatentClassConditionalLogit(BaseLatentClassModel):
    """Latent Class for ConditionalLogit."""

    def __init__(
        self,
        n_latent_classes,
        fit_method,
        coefficients=None,
        epochs=100,
        add_exit_choice=False,
        tolerance=1e-6,
        optimizer="Adam",
        lr=0.001,
        **kwargs,
    ):
        """Initialize model.

        Parameters
        ----------
        n_latent_classes : int
            Number of latent classes.
        fit_method : str
            Method to be used to estimate the model.
        coefficients : dict or MNLCoefficients
            Dictionnary containing the parametrization of the model.
            The dictionnary must have the following structure:
            {feature_name_1: mode_1, feature_name_2: mode_2, ...}
            mode must be among "constant", "item", "item-full" for now
            (same specifications as torch-choice).
        epochs : int
            Number of epochs
        add_exit_choice : bool, optional
            Whether to normalize probabilities with exit choice, by default False
        tolerance : float, optional
            LBFG-S tolerance, by default 1e-6
        optimizer : str, optional
            tf.keras.optimizers to be used, by default "Adam"
        lr : float, optional
            Learning rate to use for optimizer if relevant, by default 0.001
        """
        self.n_latent_classes = n_latent_classes
        self.fit_method = fit_method
        self.coefficients = coefficients
        self.epochs = epochs
        self.add_exit_choice = add_exit_choice
        self.tolerance = tolerance
        self.optimizer = optimizer
        self.lr = lr

        model_coefficients = {
            "coefficients": self.coefficients,
            "add_exit_choice": self.add_exit_choice,
            "optimizer": self.optimizer,
            "tolerance": self.tolerance,
            "lr": self.lr,
            "epochs": self.epochs,
        }

        super().__init__(
            model_class=ConditionalLogit,
            model_parameters=model_coefficients,
            n_latent_classes=n_latent_classes,
            fit_method=fit_method,
            epochs=epochs,
            add_exit_choice=add_exit_choice,
            tolerance=tolerance,
            optimizer=optimizer,
            lr=lr,
            **kwargs,
        )

    def instantiate_latent_models(self, choice_dataset):
        """Instantiate of the Latent Models that are SimpleMNLs.

        Parameters
        ----------
        choice_dataset: ChoiceDataset
            Used to match the features names with the model coefficients.
        """
        for model in self.models:
            model.coefficients = copy.deepcopy(self.coefficients)
            model.instantiate(choice_dataset)

    def instantiate(self, choice_dataset):
        """Instantiate of the Latent Class MNL model."""
        self.latent_logits = tf.Variable(
            tf.random_normal_initializer(0.0, 0.02, seed=42)(shape=(self.n_latent_classes - 1,)),
            name="Latent-Logits",
        )

        self.models = [self.model_class(**mp) for mp in self.model_parameters]

        self.instantiate_latent_models(choice_dataset)

    def add_coefficients(
        self, coefficient_name, feature_name, items_indexes=None, items_names=None
    ):
        """Add a coefficient to the model throught the specification of the utility.

        Parameters
        ----------
        coefficient_name : str
            Name given to the coefficient.
        feature_name : str
            features name to which the coefficient is associated. It should work with
            the names given.
            in the ChoiceDataset that will be used for parameters estimation.
        items_indexes : list of int, optional
            list of items indexes (in the ChoiceDataset) for which we need to add a coefficient,
            by default None
        items_names : list of str, optional
            list of items names (in the ChoiceDataset) for which we need to add a coefficient,
            by default None

        Raises
        ------
        ValueError
            When names or indexes are both not specified.
        """
        if self.coefficients is None:
            self.coefficients = MNLCoefficients()
        elif not isinstance(self.coefficients, MNLCoefficients):
            raise ValueError("Cannot add coefficient on top of a dict instantiation.")
        self.coefficients.add(
            coefficient_name=coefficient_name,
            feature_name=feature_name,
            items_indexes=items_indexes,
            items_names=items_names,
        )

    def add_shared_coefficient(
        self, coefficient_name, feature_name, items_indexes=None, items_names=None
    ):
        """Add a single, shared coefficient to the model throught the specification of the utility.

        Parameters
        ----------
        coefficient_name : str
            Name given to the coefficient.
        feature_name : str
            features name to which the coefficient is associated. It should work with
            the names given.
            in the ChoiceDataset that will be used for parameters estimation.
        items_indexes : list of int, optional
            list of items indexes (in the ChoiceDataset) for which the coefficient will be used,
            by default None
        items_names : list of str, optional
            list of items names (in the ChoiceDataset) for which the coefficient will be used,
            by default None

        Raises
        ------
        ValueError
            When names or indexes are both not specified.
        """
        if self.coefficients is None:
            self.coefficients = MNLCoefficients()
        elif not isinstance(self.coefficients, MNLCoefficients):
            raise ValueError("Cannot add shared coefficient on top of a dict instantiation.")
        self.coefficients.add_shared(
            coefficient_name=coefficient_name,
            feature_name=feature_name,
            items_indexes=items_indexes,
            items_names=items_names,
        )

    def fit(self, choice_dataset, **kwargs):
        """Fit the model to the choice_dataset.

        Parameters
        ----------
        choice_dataset : ChoiceDataset
            Dataset to fit the model to.
        """
        if not self.instantiated:
            self.instantiate(choice_dataset=choice_dataset)
        return super().fit(choice_dataset, **kwargs)

`init(n_latent_classes, fit_method, coefficients=None, epochs=100, add_exit_choice=False, tolerance=1e-06, optimizer='Adam', lr=0.001, **kwargs)`

Initialize model.

Parameters:

Name	Type	Description	Default
`n_latent_classes`	`int`	Number of latent classes.	required
`fit_method`	`str`	Method to be used to estimate the model.	required
`coefficients`	`dict or MNLCoefficients`	Dictionnary containing the parametrization of the model. The dictionnary must have the following structure: {feature_name_1: mode_1, feature_name_2: mode_2, ...} mode must be among "constant", "item", "item-full" for now (same specifications as torch-choice).	`None`
`epochs`	`int`	Number of epochs	`100`
`add_exit_choice`	`bool`	Whether to normalize probabilities with exit choice, by default False	`False`
`tolerance`	`float`	LBFG-S tolerance, by default 1e-6	`1e-06`
`optimizer`	`str`	tf.keras.optimizers to be used, by default "Adam"	`'Adam'`
`lr`	`float`	Learning rate to use for optimizer if relevant, by default 0.001	`0.001`

Source code in choice_learn/models/latent_class_mnl.py

def __init__(
    self,
    n_latent_classes,
    fit_method,
    coefficients=None,
    epochs=100,
    add_exit_choice=False,
    tolerance=1e-6,
    optimizer="Adam",
    lr=0.001,
    **kwargs,
):
    """Initialize model.

    Parameters
    ----------
    n_latent_classes : int
        Number of latent classes.
    fit_method : str
        Method to be used to estimate the model.
    coefficients : dict or MNLCoefficients
        Dictionnary containing the parametrization of the model.
        The dictionnary must have the following structure:
        {feature_name_1: mode_1, feature_name_2: mode_2, ...}
        mode must be among "constant", "item", "item-full" for now
        (same specifications as torch-choice).
    epochs : int
        Number of epochs
    add_exit_choice : bool, optional
        Whether to normalize probabilities with exit choice, by default False
    tolerance : float, optional
        LBFG-S tolerance, by default 1e-6
    optimizer : str, optional
        tf.keras.optimizers to be used, by default "Adam"
    lr : float, optional
        Learning rate to use for optimizer if relevant, by default 0.001
    """
    self.n_latent_classes = n_latent_classes
    self.fit_method = fit_method
    self.coefficients = coefficients
    self.epochs = epochs
    self.add_exit_choice = add_exit_choice
    self.tolerance = tolerance
    self.optimizer = optimizer
    self.lr = lr

    model_coefficients = {
        "coefficients": self.coefficients,
        "add_exit_choice": self.add_exit_choice,
        "optimizer": self.optimizer,
        "tolerance": self.tolerance,
        "lr": self.lr,
        "epochs": self.epochs,
    }

    super().__init__(
        model_class=ConditionalLogit,
        model_parameters=model_coefficients,
        n_latent_classes=n_latent_classes,
        fit_method=fit_method,
        epochs=epochs,
        add_exit_choice=add_exit_choice,
        tolerance=tolerance,
        optimizer=optimizer,
        lr=lr,
        **kwargs,
    )

`add_coefficients(coefficient_name, feature_name, items_indexes=None, items_names=None)`

Add a coefficient to the model throught the specification of the utility.

Parameters:

Name	Type	Description	Default
`coefficient_name`	`str`	Name given to the coefficient.	required
`feature_name`	`str`	features name to which the coefficient is associated. It should work with the names given. in the ChoiceDataset that will be used for parameters estimation.	required
`items_indexes`	`list of int`	list of items indexes (in the ChoiceDataset) for which we need to add a coefficient, by default None	`None`
`items_names`	`list of str`	list of items names (in the ChoiceDataset) for which we need to add a coefficient, by default None	`None`

Raises:

Type	Description
`ValueError`	When names or indexes are both not specified.

Source code in choice_learn/models/latent_class_mnl.py

def add_coefficients(
    self, coefficient_name, feature_name, items_indexes=None, items_names=None
):
    """Add a coefficient to the model throught the specification of the utility.

    Parameters
    ----------
    coefficient_name : str
        Name given to the coefficient.
    feature_name : str
        features name to which the coefficient is associated. It should work with
        the names given.
        in the ChoiceDataset that will be used for parameters estimation.
    items_indexes : list of int, optional
        list of items indexes (in the ChoiceDataset) for which we need to add a coefficient,
        by default None
    items_names : list of str, optional
        list of items names (in the ChoiceDataset) for which we need to add a coefficient,
        by default None

    Raises
    ------
    ValueError
        When names or indexes are both not specified.
    """
    if self.coefficients is None:
        self.coefficients = MNLCoefficients()
    elif not isinstance(self.coefficients, MNLCoefficients):
        raise ValueError("Cannot add coefficient on top of a dict instantiation.")
    self.coefficients.add(
        coefficient_name=coefficient_name,
        feature_name=feature_name,
        items_indexes=items_indexes,
        items_names=items_names,
    )

`add_shared_coefficient(coefficient_name, feature_name, items_indexes=None, items_names=None)`

Add a single, shared coefficient to the model throught the specification of the utility.

Parameters:

Name	Type	Description	Default
`coefficient_name`	`str`	Name given to the coefficient.	required
`feature_name`	`str`	features name to which the coefficient is associated. It should work with the names given. in the ChoiceDataset that will be used for parameters estimation.	required
`items_indexes`	`list of int`	list of items indexes (in the ChoiceDataset) for which the coefficient will be used, by default None	`None`
`items_names`	`list of str`	list of items names (in the ChoiceDataset) for which the coefficient will be used, by default None	`None`

Raises:

Type	Description
`ValueError`	When names or indexes are both not specified.

Source code in choice_learn/models/latent_class_mnl.py

def add_shared_coefficient(
    self, coefficient_name, feature_name, items_indexes=None, items_names=None
):
    """Add a single, shared coefficient to the model throught the specification of the utility.

    Parameters
    ----------
    coefficient_name : str
        Name given to the coefficient.
    feature_name : str
        features name to which the coefficient is associated. It should work with
        the names given.
        in the ChoiceDataset that will be used for parameters estimation.
    items_indexes : list of int, optional
        list of items indexes (in the ChoiceDataset) for which the coefficient will be used,
        by default None
    items_names : list of str, optional
        list of items names (in the ChoiceDataset) for which the coefficient will be used,
        by default None

    Raises
    ------
    ValueError
        When names or indexes are both not specified.
    """
    if self.coefficients is None:
        self.coefficients = MNLCoefficients()
    elif not isinstance(self.coefficients, MNLCoefficients):
        raise ValueError("Cannot add shared coefficient on top of a dict instantiation.")
    self.coefficients.add_shared(
        coefficient_name=coefficient_name,
        feature_name=feature_name,
        items_indexes=items_indexes,
        items_names=items_names,
    )

`fit(choice_dataset, **kwargs)`

Fit the model to the choice_dataset.

Parameters:

Name	Type	Description	Default
`choice_dataset`	`ChoiceDataset`	Dataset to fit the model to.	required

Source code in choice_learn/models/latent_class_mnl.py

def fit(self, choice_dataset, **kwargs):
    """Fit the model to the choice_dataset.

    Parameters
    ----------
    choice_dataset : ChoiceDataset
        Dataset to fit the model to.
    """
    if not self.instantiated:
        self.instantiate(choice_dataset=choice_dataset)
    return super().fit(choice_dataset, **kwargs)

`instantiate(choice_dataset)`

Instantiate of the Latent Class MNL model.

Source code in choice_learn/models/latent_class_mnl.py

def instantiate(self, choice_dataset):
    """Instantiate of the Latent Class MNL model."""
    self.latent_logits = tf.Variable(
        tf.random_normal_initializer(0.0, 0.02, seed=42)(shape=(self.n_latent_classes - 1,)),
        name="Latent-Logits",
    )

    self.models = [self.model_class(**mp) for mp in self.model_parameters]

    self.instantiate_latent_models(choice_dataset)

`instantiate_latent_models(choice_dataset)`

Instantiate of the Latent Models that are SimpleMNLs.

Parameters:

Name	Type	Description	Default
`choice_dataset`		Used to match the features names with the model coefficients.	required

Source code in choice_learn/models/latent_class_mnl.py

def instantiate_latent_models(self, choice_dataset):
    """Instantiate of the Latent Models that are SimpleMNLs.

    Parameters
    ----------
    choice_dataset: ChoiceDataset
        Used to match the features names with the model coefficients.
    """
    for model in self.models:
        model.coefficients = copy.deepcopy(self.coefficients)
        model.instantiate(choice_dataset)