arch.univariate.ARCHInMean.compute_param_cov¶ ARCHInMean.compute_param_cov(params: ndarray[tuple[int], dtype[float64]], backcast: float | ndarray[tuple[int], dtype[float64]] | None = None, robust: bool = True) → ndarray[tuple[int, ...], dtype[float64]]¶ Computes parameter covariances using numerical derivatives. Parameters:¶ params: ndarray[tuple[int], dtype[float64]]¶Model parameters backcast: float | ndarray[tuple[int], dtype[float64]] | None = None¶Value to use for pre-sample observations robust: bool = True¶Flag indicating whether to use robust standard errors (True) or classic MLE (False)