arch.univariate.ConstantVariance.compute_variance

ConstantVariance.compute_variance(parameters: ndarray[tuple[int], dtype[float64]], resids: ndarray[tuple[int], dtype[float64]] | Series, sigma2: ndarray[tuple[int], dtype[float64]], backcast: float | ndarray[tuple[int], dtype[float64]], var_bounds: ndarray[tuple[int, int], dtype[float64]]) → ndarray[tuple[int], dtype[float64]][source]

Compute the variance for the ARCH model.

Parameters:
parameters: ndarray[tuple[int], dtype[float64]]

Model parameters.

resids: ndarray[tuple[int], dtype[float64]] | Series

Vector of mean zero residuals.

sigma2: ndarray[tuple[int], dtype[float64]]

Array with same size as resids to store the conditional variance.

backcast: float | ndarray[tuple[int], dtype[float64]]

Value to use when initializing ARCH recursion. Can be an array_like when the model contains multiple components.

var_bounds: ndarray[tuple[int, int], dtype[float64]]

Array containing columns of lower and upper bounds.

Returns:

sigma2 – The array of conditional variances, which is also modified in place.

Return type:

numpy.ndarray