statsmodels.discrete.count_model.ZeroInflatedNegativeBinomialResults.set_null_options¶

ZeroInflatedNegativeBinomialResults.set_null_options(llnull=None, attach_results=True, **kwargs)¶

Set the fit options for the Null (constant-only) model.

This resets the cache for related attributes which is potentially fragile. This only sets the option, the null model is estimated when llnull is accessed, if llnull is not yet in cache.

Parameters:¶

llnull{None, float}

If llnull is not None, then the value will be directly assigned to the cached attribute “llnull”.

attach_resultsbool

Sets an internal flag whether the results instance of the null model should be attached. By default without calling this method, thenull model results are not attached and only the loglikelihood value llnull is stored.

**kwargs

Additional keyword arguments used as fit keyword arguments for the null model. The override and model default values.

Notes

Modifies attributes of this instance, and so has no return.