def METHOD_NAME(
    self,
    fun_evals: np.ndarray,
    gram_cho_factor: Tuple[np.ndarray, bool],
    bq_state: BQState,
) -> FloatLike:
    """Estimate the scale parameter."""
    if self.scale_estimation is None:
        new_scale_sq = bq_state.scale_sq
    elif self.scale_estimation == "mle":
        new_scale_sq = (
            fun_evals
            @ self.gram_cho_solve(gram_cho_factor, fun_evals)
            / fun_evals.shape[0]
        )
    else:
        raise ValueError(f"Scale estimation ({self.scale_estimation}) is unknown.")
    return new_scale_sq