@classmethod
def with_default_starting_params(cls, y, components):
    """Factory method for starting model parameters.

        Parameters
        ----------
        y: array-like of floats
            Time series
        components: Components
            Components used in the model

        Returns
        -------
        ModelParams
            Default starting params.
        """
    alpha = 0.09
    if components.seasonal_periods.sum() > 16:
        alpha = 1e-06
    beta = None
    phi = None
    if components.use_trend:
        beta = 0.05
        if components.seasonal_periods.sum() > 16:
            beta = 5e-07
        phi = 1
        if components.use_damped_trend:
            phi = 0.999
    gamma_params = None
    if len(components.seasonal_periods) > 0:
        gamma_params = [0.001] * components.gamma_params_amount()
    box_cox_lambda = cls.find_initial_box_cox_lambda(y, components)
    return cls(components=components, alpha=alpha, beta=beta, phi=phi,
        gamma_params=gamma_params, box_cox_lambda=box_cox_lambda)
