Fit the model using maximum likelihood.
The rest of the docstring is from statsmodels.base.model.LikelihoodModel.fit
Fit method for likelihood based models
Parameters:  start_params : arraylike, optional
method : str, optional
maxiter : int, optional
full_output : bool, optional
disp : bool, optional
fargs : tuple, optional
callback : callable callback(xk), optional
retall : bool, optional
skip_hessian : bool, optional
kwargs : keywords


Notes
The ‘basinhopping’ solver ignores maxiter, retall, full_output explicit arguments.
Optional arguments for solvers (see returned Results.mle_settings):
'newton'
tol : float
Relative error in params acceptable for convergence.
'nm'  Nelder Mead
xtol : float
Relative error in params acceptable for convergence
ftol : float
Relative error in loglike(params) acceptable for
convergence
maxfun : int
Maximum number of function evaluations to make.
'bfgs'
gtol : float
Stop when norm of gradient is less than gtol.
norm : float
Order of norm (np.Inf is max, np.Inf is min)
epsilon
If fprime is approximated, use this value for the step
size. Only relevant if LikelihoodModel.score is None.
'lbfgs'
m : int
This many terms are used for the Hessian approximation.
factr : float
A stop condition that is a variant of relative error.
pgtol : float
A stop condition that uses the projected gradient.
epsilon
If fprime is approximated, use this value for the step
size. Only relevant if LikelihoodModel.score is None.
maxfun : int
Maximum number of function evaluations to make.
bounds : sequence
(min, max) pairs for each element in x,
defining the bounds on that parameter.
Use None for one of min or max when there is no bound
in that direction.
'cg'
gtol : float
Stop when norm of gradient is less than gtol.
norm : float
Order of norm (np.Inf is max, np.Inf is min)
epsilon : float
If fprime is approximated, use this value for the step
size. Can be scalar or vector. Only relevant if
Likelihoodmodel.score is None.
'ncg'
fhess_p : callable f'(x,*args)
Function which computes the Hessian of f times an arbitrary
vector, p. Should only be supplied if
LikelihoodModel.hessian is None.
avextol : float
Stop when the average relative error in the minimizer
falls below this amount.
epsilon : float or ndarray
If fhess is approximated, use this value for the step size.
Only relevant if Likelihoodmodel.hessian is None.
'powell'
xtol : float
Linesearch error tolerance
ftol : float
Relative error in loglike(params) for acceptable for
convergence.
maxfun : int
Maximum number of function evaluations to make.
start_direc : ndarray
Initial direction set.
'basinhopping'
niter : integer
The number of basin hopping iterations.
niter_success : integer
Stop the run if the global minimum candidate remains the
same for this number of iterations.
T : float
The "temperature" parameter for the accept or reject
criterion. Higher "temperatures" mean that larger jumps
in function value will be accepted. For best results
`T` should be comparable to the separation (in function
value) between local minima.
stepsize : float
Initial step size for use in the random displacement.
interval : integer
The interval for how often to update the `stepsize`.
minimizer : dict
Extra keyword arguments to be passed to the minimizer
`scipy.optimize.minimize()`, for example 'method'  the
minimization method (e.g. 'LBFGSB'), or 'tol'  the
tolerance for termination. Other arguments are mapped from
explicit argument of `fit`:
 `args` < `fargs`
 `jac` < `score`
 `hess` < `hess`