@classmethod
def cst_bic(cls, dim, alpha):
    """
        Compute the BIC constant:

            :math:`cst  = \\frac{1}{2} \\alpha \\left(d + \\frac{d(d+1)}{2}\\right)`

        where :math:`d`is the feature dimension (*dim*)
        and :math:`alpha` a threshold (*alpha*)

        :param dim: the feature dimension
        :param alpha: the threshold
        :return: the constant
        """
    return 0.5 * alpha * (dim + 0.5 * ((dim + 1) * dim))
