statsmodels.gam.generalized_additive_model.GLMGam.fit#

GLMGam.fit(start_params=None, maxiter=1000, method='pirls', tol=1e-08, scale=None, cov_type='nonrobust', cov_kwds=None, use_t=None, full_output=True, disp=False, max_start_irls=3, **kwargs)[source]#

Estimate parameters and create instance of GLMGamResults class

Most parameters are the same as for GLM and are only used to create the results instance.

Parameters:
start_paramsarray_like, optional

Initial guess of the solution for the loglikelihood maximization. If None, then the default for method="pirls" uses the family-specific starting mu, otherwise it is passed through to the underlying optimizer.

maxiterint, optional

Maximum number of iterations. Default is 1000.

methodstr, optional

The special optimization method is “pirls” which uses a penalized version of IRLS. This is the default. Other methods are gradient optimizers as used in base.model.LikelihoodModel.fit that are called on the penalized log-likelihood.

tolfloat, optional

Convergence tolerance for “pirls”. Default is 1e-8.

scalestr or float, optional

scale can be ‘X2’, ‘dev’, or a float. See GLM.fit for details.

cov_typestr, optional

The type of parameter estimate covariance matrix to compute.

cov_kwdsdict-like, optional

Extra arguments for calculating the covariance of the parameter estimates.

use_tbool, optional

If True, the Student t-distribution is used for inference.

full_outputbool, optional

Set to True to have all available output in the Results object’s mle_retvals attribute. Not used if method is “pirls”.

dispbool, optional

Set to True to print convergence messages. Not used if method is “pirls”.

max_start_irlsint, optional

The number of PIRLS iterations used to obtain starting values for gradient optimization. Only relevant if method is set to something other than “pirls”.

**kwargs

Additional keyword arguments used in the call to the underlying optimizer.

Returns:
resinstance of wrapped GLMGamResults