try:
from IPython.display import display
from ipywidgets import HBox, VBox, interactive_output
except ImportError:
pass
from preliz.internal.plot_helper import get_textboxes
from preliz.ppls.agnostic import (
inspect_source,
parse_function_for_pred_textboxes,
ppl_plot_decorator,
)
[docs]
def predictive_explorer(
fmodel,
samples=50,
kind_plot="ecdf",
references=None,
plot_func=None,
engine="auto",
group="prior_predictive",
var_name=None,
stats_kwargs=None,
):
"""
Explore how changing parameters in the prior affects the prior predictive distribution.
Use this function to interactively explore how a prior predictive distribution changes
when the priors are changed. It also allows you to visualize how one prior changes when
another prior is changed, this can be useful for prior that are not set independently, but
are dependent on each other.
Parameters
----------
fmodel : callable
A function with a PreliZ model, a PyMC model, or a Bambi model.
See examples section below for details
samples : int, optional
The number of samples to draw from the prior predictive distribution (default is 50).
kind_plot : str, optional
The type of plot to display. Defaults to "kde". Options are "hist" (histogram),
"kde" (kernel density estimate), "ecdf" (empirical cumulative distribution function).
references : int, float, list, tuple or dictionary
Value(s) used as reference points representing prior knowledge. For example expected
values or values that are considered extreme. Use a dictionary for labeled references.
plot_func : function
Custom matplotlib code. Defaults to None. ``kind_plot`` and ``references`` are ignored
if ``plot_func`` is specified.
engine : str, optional
Library used to define the fmodel. Either `preliz`, `pymc` or `bambi`. Default is `auto`.
The function will automatically select the appropriate library to use based on the fmodel
provided.
group : str, optional
Which group to use. Ignored if the model is defined in `preliz`.
Defaults to "prior_predictive". You can also pass "prior".
var_name: str, optional
The name of the variable to plot. Ignored if the model is defined in `preliz`.
If "group=prior_predictive" it defaults to the first variable in `observed_RVs`.
For "prior" it defaults to the last variable in `free_RVs`.
stats_kwargs : dict, optional
Additional keyword arguments to pass to the statistics function.
Defaults to an empty dictionary.
"""
if stats_kwargs is None:
stats_kwargs = {}
source, signature, engine = inspect_source(fmodel)
model = parse_function_for_pred_textboxes(source, signature, engine)
textboxes = get_textboxes(signature, model, kind_plot)
new_fmodel = ppl_plot_decorator(
fmodel, samples, kind_plot, references, plot_func, engine, group, var_name, stats_kwargs
)
out = interactive_output(new_fmodel, textboxes)
default_names = [
"__kind__",
"__set_xlim__",
"__x_min__",
"__x_max__",
"__set_ylim__",
"__y_min__",
"__y_max__",
"__resample__",
]
default_controls = [textboxes[name] for name in default_names]
params_controls = [v for k, v in textboxes.items() if k not in default_names]
params_plot = VBox(params_controls + [out])
display(HBox([params_plot, VBox(default_controls)]))
